for Journals by Title or ISSN
for Articles by Keywords
help

Publisher: Elsevier   (Total: 2812 journals)

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

  First | 22 23 24 25 26 27 28 29     

The end of the list has been reached. Please navigate to previous pages.

  First | 22 23 24 25 26 27 28 29     

Journal Cover   Livestock Science
  [SJR: 0.715]   [H-I: 69]   [5 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1871-1413
   Published by Elsevier Homepage  [2812 journals]
  • Comparing environmental impacts of beef production systems: A review of
           life cycle assessments
    • Abstract: Publication date: Available online 25 June 2015
      Source:Livestock Science
      Author(s): M. de Vries , C.E. van Middelaar , I.J.M. de Boer
      Livestock production, and especially beef production, has a major impact on the environment. Environmental impacts, however, vary largely among beef systems. Understanding these differences is crucial to mitigate impacts of future global beef production. The objective of this research, therefore, was to compare cradle-to-farm-gate environmental impacts of beef produced in contrasting systems. We reviewed 14 studies that compared contrasting systems using life cycle assessment (LCA). Systems studied were classified by three main characteristics of beef production: origin of calves (bred by a dairy cow or a suckler cow), type of production (organic or non-organic) and type of diet fed to fattening calves (<50% (roughage-based) or ≥50% (concentrate-based) concentrates). This review yielded lower global warming potential (GWP; on average 41% lower), acidification potential (41% lower), eutrophication potential (49% lower), energy use (23% lower) and land use (49% lower) per unit of beef for dairy-based compared with suckler-based systems. In suckler-based systems, maintaining the mother cow is the dominant contributor to all impacts, which is attributable to the low reproductive rate of cattle and the fact that all emissions are allocated to the production of beef. GWP was slightly lower (on average 7%) for organic compared with non-organic systems, whereas organic systems showed higher eutrophication potential, acidification potential and land use (36%, 56%, and 22% higher), and lower energy use (30% lower) per unit of beef produced. Except for GWP, however, these results should be interpreted with care because impacts were compared in few studies. Lower GWP (on average 28% lower), energy use (13% lower) and land use (41% lower) per unit of beef were found for concentrate-based compared with roughage-based systems, whereas no clear pattern was found for acidification and eutrophication potential. An LCA comparison of beef systems that differ in type of diet, however, is limited because current LCA methodology does not account for the competition for land between humans and animals. To enhance future food supply, grassland less suitable for crop production, therefore, might be preferred over high productive cropland for direct production of animal feed. Furthermore, studies included in our review did not include all relevant impact categories, such as loss of biodiversity or water use. We concluded that beef production from dual-purpose cows or dairy cows inseminated with beef breeds show largest potential to mitigate environmental impacts of beef. Marginal grasslands unsuitable for dairy farming may be used for production of suckler-based beef to contribute to availability and access to animal-source food.


      PubDate: 2015-06-27T13:07:03Z
       
  • Crude glycerin changes ruminal parameters, in vitro greenhouse gas
           profile, and bacterial fractions of beef cattle
    • Abstract: Publication date: Available online 26 June 2015
      Source:Livestock Science
      Author(s): E.H.C.B. van Cleef , M.T.C. Almeida , H.L. Perez , F.O.S. van Cleef , D.A.V. Silva , J.M.B. Ezequiel
      As the biodiesel industry produces a large surplus of crude glycerin, this by-product is increasingly being considered as an attractive source of energy to replace corn in livestock diets. The objective of this study was to evaluate how the inclusion of up to 30% crude glycerin in Nellore cattle diets affects ruminal parameters such as pH, ammonia, and volatile fatty acids as well as greenhouse gas production, and concentration of the protozoal and bacterial fractions. Five ruminally cannulated Nellore steers were randomly assigned in a 5 × 5 Latin square design and fed diets containing 30% corn silage and 70% concentrate composed of sunflower meal, corn grain, soybean hulls, minerals, and 0, 7.5, 15, 22.5, or 30% crude glycerin (860g glycerol/kg). After 14 d of adaptation, animals were submitted to rumen content sampling for 7 d. With the supplementation of glycerin in the diets, total VFA and acetate concentrations decreased (linear, P= 0.03, P< 0.0001, respectively), and propionate concentrations increased (linear, P= 0.007; quadratic, P= 0.008), leading to an acetate to propionate ratio decrease (linear, P< 0.0001). The rumen ammonia was not affected while pH was quadratically affected and was lesser for glycerin treatments (quadratic, P= 0.04). Methane production was reduced (linear, P< 0.0001) when glycerin was added, as well as the CO2 (linear, P< 0.0001; quadratic, P= 0.0001; cubic, P< 0.0001). The concentration of liquid phase microorganisms was not affected, while the concentration of particle-associated bacteria fraction was decreased by the addition of crude glycerin in the diets. The inclusion of up to 30% of crude glycerin in diets for beef cattle decreased ruminal concentration of total VFA and acetate, increased propionate, reduced concentration of particle-associated bacteria, and decreased production of methane.


      PubDate: 2015-06-27T13:07:03Z
       
  • Effect of SIRT1 on cellular apoptosis and steroidogenesis in bovine
           ovarian granulosa cells in vitro
    • Abstract: Publication date: Available online 25 June 2015
      Source:Livestock Science
      Author(s): X.W. Tan , W. You , E.L. Song , H.B. Zhao , X.M. Liu , H.Z. Wang , G.F. Liu , H.J. Cheng , Y.F. Liu , F.C. Wan
      Sirtuin type 1 (SIRT1) gene plays an important role in the regulation of female reproduction, and we set out to determine if SIRT1 plays a role in steroidogenesis. In this study, granulosa cells isolated from bovine ovaries were cultured and treated with resveratrol or nicotinamide, respectively. The mRNA and protein levels of SIRT1 of cultured granulosa cells were investigated by quantitative real-time RT-PCR and Western blot, and then the extent of cellular apoptosis was measured by FACS assay. The amounts of estradiol and progesterone in cultured media were measured by radioimmunoassay, and mRNA and protein levels of Steroidogenic Factor 1 (SF-1) were also investigated. We demonstrated that resveratrol exhibited a dose-dependent induction of SIRT1 expression, which induced late apoptosis in granulosa cells, while the same results were not observed in the treatment of nicotinamide. We observed the estradiol levels and SF-1 expression decreased while progesterone level increased after the treatment of resveratrol, but the opposite results were observed in the treatment of nicotinamide. In conclusion, SIRT1 affected apoptosis, steroidogenesis and the related gene expression in granulosa cells, which may provide new insight into the treatment of follicular and/or luteal phase deficiency.


      PubDate: 2015-06-27T13:07:03Z
       
  • Editorial Board
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177




      PubDate: 2015-06-25T13:02:53Z
       
  • A multi-compartment model for genomic selection in multi-breed populations
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): El Hamidi Hay , Romdhane Rekaya
      Genome wide evaluation methods are often conducted using purebred populations. Estimation and often validation are carried out using primarily select elite animals. This process is successful when estimated SNP effects are used to predict genomic breeding values of animals of similar breed. This approach fails when SNP estimates in one breed are used for genomic prediction in other breeds. In this study, we proposed a multi-compartment model where the effect of an SNP marker could differ between breeds. Two simulation scenarios were carried out using an admixed population of two divergent lines (A and B), first using a low density panel (300 SNPs) and second using a high density panel (60k SNPs). Divergence between the two lines was artificially created by multiplying marker effects in one line by a variable α which was sampled from different uniform or normal distributions. The proposed method was compared to the pooled data approach based on the accuracy of predicting the true breeding values. In the first simulation scenario, the prediction accuracy using the pooled data approach for line A, was 0.40, 0.39 and 0.38 when α was generated from a uniform distribution between [−2, 2], [−4, 4] and [−8, 8] respectively. Using our proposed method, the corresponding accuracies were 0.47, 0.46 and 0.46, respectively. A similar trend was observed for line B with a clear superiority of the multi-compartment model over the pooled data approach with an increase ranging from 17 to 47% and increases as the divergence between lines increases. In the second scenario, when α was sampled from a uniform [−2.2], accuracy for line A (B) was 0.32 (0.30) using pooled data model, and 0.33 (0.32) using the multi-compartment model. Although smaller than in first simulation scenario, the proposed method still has a superiority of 3 to 7%. Similar performance was observed when α was sampled from uniform [−4,4].


      PubDate: 2015-06-25T13:02:53Z
       
  • Comparison of fixed effects and mixed model growth functions in modelling
           and predicting live weight in pigs
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): J.M. Coyne , D.P. Berry , E.A. Mäntysaari , J. Juga , N. McHugh
      The objective of the present study was to compare alternative growth functions fitted to pig live weight data, with particular emphasis on the function׳s ability to predict future animal live weight. The final dataset consisted of 51,893 live weight records from 10,201 pigs aged between 61 and 200 days. Fixed effects models and mixed models were applied to the three different growth functions: von Bertalanffy, Gompertz, and Richards; fixed and mixed model polynomial equations were also considered. The growth function׳s ability to predict future live weight was determined by excluding a selection of animal live weight records post 160 days of age and comparing the predicted live weight to actual live weight. Irrespective of whether a fixed or mixed model framework was used, the Gompertz function best modelled the full dataset, with an accuracy squared for the full dataset ( r w 2 ) of 0.997 and root mean square error (RMSE) of 1.60kg for the fixed effects model and r w 2 of 0.995 and RMSE of 2.25kg for the mixed model equation. The Gompertz mixed model also achieved the greatest accuracy squared of predicting ( r w w ^ 2 ) future live weight records, with an r w w ^ 2 of 0.846 and RMSE of 5.35kg. A strong positive correlation was estimated between asymptotic mature weight (A; r=0.83 to 0.96) across the three growth functions for all considered equations. A strong negative correlation was estimated between parameters A and k (rate of maturation) for the Gompertz fixed effects model (−0.88) and mixed model (−0.70). Results from this study could be used to implement a decision support tool for pork producers, offering extra information when they are making important feeding, slaughter and breeding decisions.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effects of heat stress on semen characteristics of Holstein bulls
           estimated on a continuous phenotypic and genetic scale
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): A. Al-Kanaan , S. König , K. Brügemann
      Semen volume (SV), semen output (SO), semen motility (SM), number of semen doses per ejaculate (NSD) and semen concentration (SC) were analyzed on a phenotypic and quantitative genetic scale in dependency of the continuous environmental descriptor THI (=an index describing combinations of temperature with humidity). Longitudinal semen data included 10,341 observations from 562 Holstein sires kept on an AI station in the northwestern part of Germany. Statistical modeling was based on fixed and random regression methodology (RRM). In this context, the phenotypic and genetic trajectory of traits in dependency of THI was modeled by orthogonal polynomials, i.e. Legendre polynomials of order 3. A general heat stress threshold of THI=60 was identified, and indicating detrimental effects of heat stress beyond this threshold, especially on SV, SO, NSD, and SC. Least square means for semen productivity were generally higher for adult bulls, but compared to young bulls, adult bulls responded with stronger semen production losses for extremely high THI. The optimal environment for semen production was a THI in the range from 50 to 60. Detrimental impact of heat stress was reduced for bulls with longer intervals between consecutive semen collection dates. Heritabilities for semen traits were in a low to moderate range with the following maximal values: 0.18 for SV at THI 30, 0.29 for SM at THI 70, 0.26 for SO at THI 30, 0.26 for NSD at THI 58, and 0.27 for SC at THI 53. Genetic values of sires and additive genetic variances changed with alterations of THI, with highest genetic variances at the extreme ends of the continuous environmental descriptor. Genetic correlations in same traits from THI levels in great distance were lower than 0.80, and indicated genotype by environment interactions. Application of RRM allow to select sires according to THI specific breeding values, which implies an optimization of cow sire and bull sire selection for harsh environments.


      PubDate: 2015-06-25T13:02:53Z
       
  • Investigations into genetic variability in Holstein horse breed using
           pedigree data
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): L. Roos , D. Hinrichs , T. Nissen , J. Krieter
      A pedigree data set including 129,923 Holstein warmblood horses was analyzed to determine genetic variability, coefficients of inbreeding, the age of inbreeding and the genetic contributions of founder animals and foreign breeds. The reference population contained all horses which had been born between 1990 and 2010. The average Pedigree Completeness Index (PEC) for the reference population was determined as 0.88 and the average complete generation equivalent (GE) was computed at 5.62. The mean coefficient of inbreeding for the reference population (inbred and non-inbred horses) was 2.27%. Most of the inbreeding was defined as “new” inbreeding, which had evolved during recent generations. The effective population size and the effective number of founders were calculated to be 55.31 and 50.2 effective individuals respectively. The most influential foreign breed was the English Thoroughbred with a contribution of 25.98%, followed by Anglo Normans (16.38%) and Anglo Arabians (3.27%). At 2.75%, Hanoverian warmblood horses were determined to be the most important German horse breed. The stallions Cor de la bryere, Ladykiller xx and Cottage son xx were found to be the most important male ancestors. The mare Warthburg was defined as the most affecting female. It was possible to detect the occurrence of the loss of genetic diversity within the Holstein horse breed, related to unequal founder contributions caused by the intensive use of particular sire lines. However, a slight increase in the effective population size and a stagnation of inbreeding during the last generation might show the impact of more open access given to foreign stallions in the recent past.


      PubDate: 2015-06-25T13:02:53Z
       
  • A comparison of two enzymatic in vitro methods to predict in vivo organic
           matter digestibility of perennial ryegrass
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): M. Beecher , R. Baumont , J Aufrère , T.M. Boland , M.O’ Donovan , N. Galvin , C. Fleming , E. Lewis
      Accurate grass organic matter digestibility (OMD) values are required for intake prediction, for calculating metabolisable protein and ultimately to accurately formulate diets. The three objectives of this study were: (i) to compare the neutral detergent cellulase (NDC)- and pepsin cellulase (PC)-predicted OMD to in vivo OMD; (ii) to compare the NDC method to the PC method for accurately estimating grazed grass OMD and (iii) to compare the effect of sample preparation on the NDC method results, specifically oven drying samples at 60°C compared to freeze drying at −55°C. Data consisted of 34 forage grass samples on which OMD was measured in vivo using the total faecal collection method in sheep (OMDINVIVO). The grass samples were also analysed in vitro in triplicate. For the NDC method the samples were oven-dried at 60°C for 48h or were freeze-dried at −55°C for 1 week. The PC method samples were oven-dried at 60°C for 72h. The NDC organic matter solubility (OMS) results were inserted into the equation developed by Stakelum et al., (1988. Irish J. Agric. Res. 27, 104–105) to give OMDNDC. The OMS results from the PC method were inserted into the equation developed by Aufrère et al., (2007. INRA Prod. Anim. 20, 129–136) to give OMDPC. The comparison between OMDPC 60 (mean±standard error) (0.708±0.0361; n=34) and OMDINVIVO (0.719±0.0361) showed that there was a tendency for the two methods to give different results (P=0.06). The comparison between OMDNDC FD (0.740±0.0049; n=18) and OMDINVIVO (0.764±0.0063) showed that the two methods gave different results (P<0.01). The comparison between OMDNDC 60 (0.680±0.0265; n=34) and OMDINVIVO (0.719±0.0361) showed that the two methods gave different results (P<0.05). The positive correlation with OMDINVIVO suggested that OMDNDC FD, OMDNDC 60 and OMDPC 60 were able to predict OMDINVIVO of perennial ryegrass grazed swards. The comparison between OMDNDC FD (0.740±0.0049) and OMDPC 60 (0.746±0.0109) showed that the two methods gave similar results (P>0.05). The comparison between OMDNDC 60 (0.680±0.0230) and OMDPC 60 (0.708±0.0230) showed that the two methods tended to give different results (P=0.06). To improve the relationship between OMDINVIVO and OMDNDC FD, and between OMDINVIVO and OMDNDC 60, future work should expand the number of grass samples, the months of the year over which samples are collected and the range of chemical composition and OMDINVIVO of the samples. Sample preparation method had an effect on the NDC-predicted OMD results as OMSNDC FD differed to OMSNDC 60 and OMDNDC FD differed to OMDNDC 60. This indicated that specific correction (regression) equations must be used for specific sample preparation methods.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effect of timing of pasture allocation on production, behavior, rumen
           function, and metabolism of early lactating dairy cows during autumn
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): Rubén G. Pulido , Miguel Ruiz-Albarrán , Oscar A. Balocchi , Pamela Nannig , Fernando Wittwer
      The objective of the present study was to evaluate the effect of timing of pasture allocation on performance, feeding behavior, rumen function and plasma and urine metabolites of early-lactation dairy cows in autumn, strip-grazing a perennial ryegrass sward. Forty-two Holstein Friesian cows were randomly allocated to one of the following treatments: Pasture strips allocated daily at either 10:00h (AM-ALL), 16:50h (PM-ALL) or twice a day at 10:00 and 16:50h (AM–PM). Herbage allowance was 21kg DM/cow/day for all treatments. All cows received a daily allocation of concentrate and grass silage, 3.0 and 3.2kg DM per cow, respectively. Herbage chemical composition differed amongst treatments, as dry matter and WSC contents were greater in PM-ALL than in AM-ALL and AM–PM. Milk yield tended to be greater with PM-ALL (P=0.06) compared with AM-ALL and AM–PM. The concentration of protein tended to be greater with AM–PM (P=0.09) compared with PM-ALL and AM-ALL. Protein and urea concentrations in milk did not differ among treatments. Daily grazing, ruminating and idling times were similar among treatments (P>0.05). During the first 2h, cows in AM-ALL grazed 30 and 15min longer than cows in AM–PM and PM-ALL treatments (P<0.05). Herbage disappearance was greater (P=0.003) in PM-ALL compared with AM-ALL and AM–PM. Treatment did not affect rumen fermentation metabolites, except for the concentration of propionic acid, which was 3% lower for cows in AM–PM compared with AM-ALL and PM-ALL cows. Cows in PM-ALL had lower concentration of urea in plasma 0.88 and 0.68mmol/L less compared with cows in AM-ALL and AM–PM (P=0.04). Concentrations of urinary metabolites were not affected by treatment. These results suggest that timing of pasture strip allocation alters nutrients supplied by herbage to cows, but has only a small effect on herbage dry matter intake. Consequently, allocating the daily pasture strips in the afternoon would tend to increase milk production compared with allocations during the morning (~3) and twice a day (4.4%).


      PubDate: 2015-06-25T13:02:53Z
       
  • Prediction of the Ym factor for livestock from on-farm accessible data
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): G. Jaurena , J.M. Cantet , J.I. Arroquy , R.A. Palladino , M. Wawrzkiewicz , D. Colombatto
      Methane emission factor (Ym) is directly involved to calculate the worldwide livestock methane inventories, hence it is important to refine the estimation of this parameter for different livestock production systems. The purpose of this work was to generate refined mathematical models to predict CH4 emissions from an extensive compilated database at on-farm level and to compare them with different models already available in the literature. Methane emission predictive models (expressed as Ym, % gross energy intake; and methane production, CH 4 p, gan−1 d−1) where fitted taken into account the production system, the livestock type and the feed characteristics available at on-farm level within a reasonable uncertainty range. In order to develop the models, only easy available parameters were selected to fit new mathematical models. Hence, the full model included: ruminant types (beef cattle, dairy cattle, and sheep), fibre sources (fresh forage, conserved forage, and straw) and concentrate levels (DM basis) in the diet (Low, <35%; Intermediate, 35–65%; High, >65%). Full models were assessed by the Bayesian Information Criterion (BIC) and terms that did not reach significance level (P≤0.05) were dropped from the model. Furthermore, predicted results were assessed through correlation and regression analyses considering the model significance. Models developed in this study were compared by the degree of adjustment of a simple regression. Additive and technique terms were initially dropped from the full model used to predict Ym because they did not have effect in the prediction (P>0.10). Therefore, the final equation for Model 1 was: Ym(a)=Intercept−0.243(±0.051)×DMI (kgd−1)+5.9×10−3(±1.17×10−3)×NDF (gkg−1 DM−1)+5.7×10−3(±1.63×10−3)×DMD (gkg−1 MS−1) (BIC=559). All terms of this model, intercept factor (type of cattle×source of fibre×level of concentrate), DMI, NDF, and DMD were significant (P<0.0001). DMI was the term with the greatest weight in the model. The predicted Ym value decreased about 0.243 percentage units (P<0.0001) per each additional kg in DMI. When the equation was compared with previous publicated models, our model showed a satisfactory degree of fitting. In conclusion, this new model improved the estimation of the Ym factor from beef and dairy production systems, using different forage quality characteristics from on-farm level to increase precision.


      PubDate: 2015-06-25T13:02:53Z
       
  • Influence of ruminal Quebracho tannin extract infusion on apparent
           nutrient digestibility, nitrogen balance, and urinary purine derivatives
           excretion in heifers
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): S. Ahnert , U. Dickhoefer , F. Schulz , A. Susenbeth
      Six fully grown heifers (491kg body weight, standard deviation 35) fitted with ruminal cannulae received incremental dosages of a commercial Quebracho tannin extract (QTE) to investigate its effects on apparent total tract nutrient digestibilities, nitrogen balance, and purine derivatives excretion as an indicator of duodenal microbial crude protein flow. The basal diet comprised 2.6kg/d grass hay, 2.6kg/d concentrate feed, and 60g/d of a mineral premix (as-fed basis) and was offered in two equal meals. The QTE was administered at 0 (CON 1), 1, 2, 4, or 6% of the daily DM intake from the basal diet (i.e., 45g, 90g, 180g, and 270g/d; as-fed basis). For this, half of the daily QTE dosage was suspended in water and intraruminally infused during each feeding. All animals simultaneously received the same QTE dosage. Every period comprised 9d of adaptation and 6d of total urine and feces collection. Subsequent to highest QTE dosage, infusion was ceased and after 14d of adaptation, urine and feces were collected again for 10d (CON 2). The QTE infusions at ≥4% lowered apparent total tract organic matter digestibility (P≤0.045). The effects were more pronounced for neutral detergent and acid detergent fiber digestibilities which decreased from 0.718 and 0.626 without QTE to 0.590 and 0.493 at 6% QTE, respectively (P<0.001). Nitrogen excretion linearly decreased in urine (P=0.003) and linearly increased in feces (P<0.001) with incremental QTE dosages. Irrespective of the dosage level, nitrogen retention was higher with than without QTE infusion (P≤0.035). Urinary purine derivatives excretion declined from 103mmol/d at 1% QTE to 80mmol/d at 6% QTE (P<0.001), indicating a 36% decrease in estimated duodenal microbial crude protein flow. At QTE dosages of ≥4% of DM intake, reduced carbohydrate digestibility will lower energy supply to the host animal. The pronounced decrease in estimated microbial protein synthesis even at moderate QTE levels is unlikely to be compensated by the increase in rumen-escape protein. The QTE addition to ruminant diets might not improve protein supply and performance of cattle.


      PubDate: 2015-06-25T13:02:53Z
       
  • Energy requirements for maintenance and growth of early-weaned Dorper
           crossbred male lambs
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): G.-S. Xu , T. Ma , S.-K. Ji , K.-D. Deng , Y. Tu , C.-G. Jiang , Q.-Y. Diao
      This study aimed to investigate the net and metabolizable energy (NE and ME) requirements of Dorper crossbred lambs. Thirty-five Dorper×thin-tailed Han crossbred intact male lambs weaned at approximately 50d of age (20.26±1.29kg of BW), were used. Seven randomly selected lambs were slaughtered at the start of the trial (baseline group). An intermediate group consisting of 7 randomly selected lambs fed for ad libitum intake was slaughtered when the lambs reached an average BW of 28.2kg. The remaining 21 lambs were alloted randomly to 3 levels of dry matter intake: ad libitum, or restricted to 70 or 40% of the ad libitum intake. All the lambs were slaughtered when the ad libitum fed sheep reached 35kg of BW. Total body energy, crude protein, fat, ash, and moisture contents were determined. In a digestibility trial, fifteen Dorper×thin-tailed Han crossbred intact male lambs (32.38±2.23kg of BW) were housed in metabolism cages and used in a completely randomized design experiment to evaluate the ME value of the diet at 3 feed intake levels. The results showed that the maintenance requirements for NE and ME were 250.61 and 374.21kJ/kg metabolic shrunk body weight (SBW0.75), respectively. The partial efficiency of energy use for maintenance was 0.67. Net energy requirements for growth ranged from 1.12 to 5.31MJ/d, for the lambs gaining 100 to 350g/d from 20 to 35kg BW. Partial efficiency of ME for growth was 0.42. In conclusion, the current study suggested that the NE requirement for maintenance and growth of Dorper×thin-tailed Han early-weaned crossbred lambs were lower than those reported by existing AFRC and NRC nutritional systems.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effects of diets with high and low protein contents and two concentrate
           levels in Santa Ines×Texel lambs
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): R.S. Santos , K.G. Ribeiro , S.C.Valadares Filho , O.G. Pereira , S.D.J. Villela , L.N. Rennó , J.L. Silva
      Two experiments were conducted to evaluate the effects of diets containing two levels of crude protein (CP) and concentrates on the intake, total nutrient digestibility, nitrogen balance (NB), microbial efficiency, and performance of lambs. The diets consisted of 10% or 14.25% CP and 40% or 60% concentrate, with corn silage as the forage. In the digestibility assay, four intact male F1 Santa Ines×Texel lambs, with an average body weight of 21.0±2.48kg and rumen-cannulated, were used. The lambs were distributed in a 4×4 Latin square design with four treatments and four periods. There was no effect of the CP×concentrate interaction on the variables that were studied. There was an effect of CP levels on the intake and digestibility of CP, as well as on the amounts of N that were ingested, absorbed, and retained from urine (NB). There was also an effect of CP levels on uric acid excretion. In the performance assay, 32 intact F1 Santa Ines×Texel lambs with an average body weight of 19.0±2.02kg were used. They were distributed in a 2×2 factorial arrangement of treatments in a randomized block design with eight replicates. There was a significant interaction between CP and concentrate levels on the ether extract (EE) intake. The CP level affected the intake of dry matter (DM), organic matter (OM), CP, neutral detergent fiber corrected for ash and protein (apNDF), non-fiber carbohydrates (NFC), total digestible nutrients (TDN), and rumen-degraded protein (RDP), as well as the carcass gain (CG) and the feed conversion (FC). Concentrate levels affected the intake of DM, OM, CP, NFC, TDN, and RDP, as well as the CG, the CG/average daily gain (ADG), and the FC. It was concluded that levels of CP and concentrate do not affect microbial efficiency or nutrient digestibility, except for CP digestibility. A high level of CP or concentrate in the diet results in greater nutrient intake and better animal performance.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effects of mulberry (Morus alba L.) leaf polysaccharides on growth
           performance, diarrhea, blood parameters, and gut microbiota of
           early-weanling pigs
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): Xiangjie Zhao , Lin Li , Qiulan Luo , Mingqiang Ye , Guoqing Luo , Zheshi Kuang
      This study aimed to investigate the effects of mulberry leaf polysaccharides (MLPs) dietary supplements on the growth performance, diarrhea, blood biochemical parameters, and gut microbiota of early weanling piglets. A total of 150 Duroc–Landrace–Yorkshire crossbred weanling pigs (age: 28±2d; body weight: 9.18±0.46kg), were used in this study. Subjects were randomly divided into five treatment groups with six replicates in each group (n=5 animals per replicate). The dietary treatments were as follows: (1) control treatment (CT): basal diet (BD); (2) low-dose MLPs treatment (LT): 0.3g/kg of MLPs+BD; (3) medium-dose MLPs treatment (MT): 0.6g/kg of MLPs+BD; (4) high-dose MLPs treatment (HT): 0.9g/kg of MLPs+BD; and (5) antibiotic treatment (AT): 0.15g/kg chlortetracycline+BD. The fasting weight of each animal was measured and recorded in the morning at three time points (0, 10, and 21d) in addition to food intake per pigpen. These data were then used to calculate the average daily gain (ADG), average daily feed intake (ADFI), and feed-to-gain (F/G) ratio of each subject. The diarrheal status of each piglet was examined and recorded twice daily (morning and afternoon). At the end of the experiment, blood samples were collected for biochemical analysis, and the contents from the ceacum, colon, and rectum were harvested to identify and quantify relevant gut microbiota. Our results showed that there was no significant differences in the ADG, ADFI, or F/G ratio among MLPs-treated groups (P>0.05), but the ADFI in LT, MT, and HT groups were all higher than those of both the CT and AT groups. Additionally, the F/G ratios in LT, MT, and HT groups were lower than those in the CT and AT groups. The LT, MT and HT groups showed a significant reduction in diarrheal incidence (P<0.05) when compared to the CT and AT groups. Biochemical analysis revealed that blood glucose (GLU) levels in all MLPs-treated groups were significantly (P<0.05) lower than in either the CT or AT groups. Blood urea nitrogen (BUN) levels in the MT and HT groups were significantly (P<0.05) different from those in CT and AT group and T3 levels in HT were significantly (P<0.05) higher than those in either the CT or AT groups. Although T4 levels in MLPs-treated groups were not significantly different from the AT control group, both IGF-1 and GH levels in the MT group were significantly higher than those in either the CT or AT groups (P<0.05). Our microbiota results indicated that the overall effects of LT, MT, and HT in both inhibiting gut Escherichia coli and in promoting gut lactobacilli and bifidobacteria were superior than those of both the CT and AT groups. Notably, the HT group (0.9g/kg MLPs) showed a significantly better inhibitory effect on gut E. coli as well as a significantly better promotional effect on gut-beneficial bacteria when compared to both the CT and AT groups (P<0.05). Collectively, these results suggest that dietary addition of MLPs can improve the ecology of gut microbiota, reduce diarrhea rate, and improve the overall growth performance in early-weanling pigs.


      PubDate: 2015-06-25T13:02:53Z
       
  • Intrauterine growth retardation increases lipid deposition in adipose
           tissue of pigs in response to high-fat/high energy diets
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): J.B. Liu , Y.K. Yang , J. He
      The objective of this study was to investigate the effects of postweaning high-fat (HF)/high energy diets on lipid metabolism response in adipose tissue of normal birth weight (NBW) and intrauterine growth retarded (IUGR) pigs. Twenty NBW and twenty IUGR male piglets were fed either a control diet (without lard) or a HF diet (supplemented with 10% lard) from weaning (d 28) to slaughter at 111.4±2.2kg of body weight. Feed intake and body weight of pigs were recorded monthly. Blood and backfat samples were collected at the end of the experiment and analyzed for plasma levels of metabolites and hormone, activities and mRNA expressions of enzymes involved in lipid metabolism. The results showed that plasma concentrations of leptin and cholesterol, backfat thickness, index of backfat thickness, and mRNA expressions of leptin and adipocyte differentiation-related protein (ADRP) in backfat were affected by the interaction of birth weight and postweaning diet (P<0.05). Compared with NBW littermates, IUGR pigs had lower average daily feed intake (ADFI) and average daily gain (ADG) but greater slaughter age and plasma levels of triglyceride (P<0.01). Lipid content, adipocyte diameter, activities of fatty acid synthase (FAS) and malic enzyme (ME), mRNA expressions of FAS and peroxisome proliferator-activated receptor gamma (PPARγ) in adipose tissue of IUGR pigs were greater than that of NBW pigs (P<0.01). Moreover, IUGR pigs had lower glucose-6-phosphate dehydrogenase (G-6-PDH) activity and mRNA levels of HSL compared with NBW pigs (P<0.01). Pigs fed HF diets had lower ADFI, slaughter age (P<0.01), mRNA expression abundances of LPL and FAS (P<0.01), and activities of FAS and ME (P<0.05) but greater ADG, plasma levels of triglyceride (P<0.05), and gain to feed ratio than pigs fed control diets. In summary, our results indicated that IUGR pigs had greater capability in adipose tissue lipid deposition than that of NBW offspring in response to postweaning HF/high energy diets.


      PubDate: 2015-06-25T13:02:53Z
       
  • Growth performance, apparent nutrient digestibility, intestinal morphology
           and carcass traits of broiler chickens fed dry, wet and fermented-wet feed
           
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): O.S. Akinola , A.O. Onakomaiya , J.A. Agunbiade , A.O. Oso
      This study seeks to investigate the growth performance, intestinal morphology, carcass traits and apparent nutrient digestibility of broiler chickens fed with dry, wet and fermented-wet feed. Three experimental diets were formulated in this study. Diet 1 was dry mash feed. Diet 2 was wet mash feed in a 1:1.3 mix with water. Diet 3, was fermented-wet mash feed in a 1:1.3 mix with water which was fermented for 24h in sealed plastic polythene bags prior to feeding. A total of 192 two-weeks-old broilers (Marshal strain) were randomly assigned to the experimental diets in a completely randomized design (CRD). Each treatment group was replicated four times with 16 birds per replicate. Each dietary treatment was fed immediately to the birds after re-constitution. Fermentation of the feed reduced (P<0.05) the pH from 6.61 to 4.37. Birds fed fermented-wet and wet mash recorded higher (P<0.05) final live weight and weight gain. Feed intake and feed conversion ratio were not affected (P>0.05) by wet and fermented-wet fed birds compared to the dry fed birds. Mortality was not affected by dietary treatment imposed. Apparent organic matter digestibility was higher (P<0.05) in birds fed fermented-wet feed when compared to birds fed with dry and wet feed. Intestinal villus morphology and carcass measurement were not affected (P>0.05) by the treatment imposed. However, birds fed wet feed showed lower (P<0.05) gizzard weight when compared to birds fed fermented-wet feed. Birds fed with fermented-wet mash recorded higher (P<0.05) abdominal fat than those fed with dry mash. The results of this study indicated fermented-wet feeding improved apparent organic matter digestibility with a resultant improved growth performance of broiler chicken.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effects of a multi-strain probiotics against aflatoxicosis in growing
           Japanese quails
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): F. Bagherzadeh Kasmani , M. Mehri
      An experiment was conducted to determine the effects of a multi-strain probiotics (PRO) on growth performance and immune status of growing Japanese quails fed aflatoxin B1 (AFB1). A total of 320 quail chicks were assigned to 4 treatments, control (basal diet), AFB1 (basal diet+2.5mg AFB1/kg), PRO (basal diet+150mg PRO/kg), and AFB1+PRO (basal diet+2.5mg AFB1 and 150mg PRO/kg) with 4 replicate pens and 20 quails per pen. The quail chicks had free access to water and experimental diets from 7 to 35 d of age, and feed intake (FI) and body weight gain (BWG) were measured weekly. Overall feed intake and BWG were reduced in AFB1 treatment (P<0.05), but feeding probiotics improved those criteria in quails received dietary AFB1 (P<0.05). During 7–35d of age, AFB1 increased FCR while the PRO supplementation decreased FCR in quails fed AFB1 diet (P<0.05). Moreover, FCR in AFB1+PRO treatment was better than PRO treatment (P<0.05). The most hypertrophy in internal organs (e.g., liver and spleen) and suppressed growth in testes and bursa of Fabricius were observed in AFB1 group but feeding PRO improved the status of these organs (P<0.05). The humoral (e.g., antibody response against sheep red blood cell antigen) and cellular responses (e.g., skin thickness against 2,4-Dinitro 1-chlorobenzene) were suppressed in quails fed AFB1 but feeding PRO boosted those immune systems (P<0.05). The use of AFB1 in diet invariably increased the levels of aspartate transaminase, alanine aminotransferase, and alkaline phosphatase in the sera of Japanese quails (P<0.05). The opposite effect was observed for aforementioned enzymes because of PRO in the diets. This study showed that under aflatoxicosis, the use of dietary multi-strain probiotics could improve the growth performance and immunocompetence in growing Japanese quails.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effect of high stocking density on performance, egg quality, and plasma
           and yolk antioxidant capacity in laying hens supplemented with organic
           chromium and vitamin C
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): R. Jahanian , E. Mirfendereski
      This study was conducted to investigate the effects of dietary supplementation of chromium–methionine (CrMet) and vitamin C on performance, egg quality measurements, and plasma antioxidant capacity in laying hens subjected to high stocking density. A total of 360 Hy-Line W-36 laying hens, 26wk of age, were used in a 2×2×3 factorial arrangement of treatments consisting of 2 cage densities [5 or 7 hens/cage (40×45cm2)], 2 supplemental vitamin C levels (0 and 500mg/kg as l-ascorbic acid), and 3 supplemental Cr levels (0, 500, and 1000μg/kg as CrMet) with 5 replicate cages per treatment. The hens were kept in wire-floor cages in an environmentally-controlled room. After a 2-wk adaptation, the 70-d study was initiated and it was divided into two 35-d periods (28–33 and 33–38wk of age). Results showed that although subjecting hens to high stocking density had no effect on egg production percentage during 28–33wk of age, it decreased (P=0.031) during the 33–38wk of age, resulting in a marked reduction (P=0.038) in egg mass. Dietary Cr supplementation (500 and 1000μg/kg) increased (P<0.01) egg production and egg mass during both 35-d periods, and improved (P=0.005) feed conversion ratio (FCR) during the first 35-d period. There was a stocking density×vitamin C interaction (P=0.018) for FCR values during the first 35-d period, so that supplemental vitamin C improved FCR to a greater extent in high stocking density-challenged hens. Dietary CrMet supplementation (500 and 1000μg/kg) increased (P=0.001) feed intake during the second 35-d period. Shell thickness was greater (P=0.015) in hens under high stocking density challenge during the second 35-d period. Subjecting hens to high stocking density decreased (P=0.007) plasma vitamin C concentration, while plasma vitamin C level was increased (P<0.05) as the result of dietary supplementation of vitamin C. Dietary supplementation of CrMet (500 and 1000μg/kg) increased plasma vitamin C level only in high stocking density-challenged hens, resulting in a stocking density×Cr interaction (P=0.039). Although high stocking density increased (P<0.05) plasma and yolk concentrations of malondialdehyde (MDA), supplemental vitamin C decreased (P<0.05) plasma and yolk MDA contents. Similarly, dietary inclusion of CrMet (500 and 1000μg/kg) decreased (P=0.046) plasma MDA level. The present findings indicate that dietary CrMet supplementation could increase antioxidant capacity in stressed hens, which improve production performance of laying hens.


      PubDate: 2015-06-25T13:02:53Z
       
  • Variables of gait inconsistency outperform basic gait variables in
           detecting mildly lame cows
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): A. Van Nuffel , W. Saeys , B. Sonck , J. Vangeyte , K.C. Mertens , B. De Ketelaere , S. Van Weyenberg
      To support herdsmen in finding the lame cows on their herds, several automated systems that measure lameness related cow features such as gait patterns, are being developed. Most of these systems are able to distinguish between non-lame and severely lame cows. Detecting mildly lame cows in an early stage of lameness however seems challenging. Inspired by the approach used in human gait research, new variables that measure the inconsistency in stride-to-stride variables were tested using cow gait and were able to show differences between a group of non-lame and a group of mildly lame cows. In order to investigate the added value of these inconsistency variables in detecting mildly lame cows, two new lameness detection models were build: one using solely basic gait variables and a second model using both basic and the new gait inconsistency variables. The second model using the gait inconsistency variables outperformed the model based on only basic gait variables by far in detecting the mildly lame cows with a sensitivity of 88% and a specificity of 87%. These results support the suggestion of incorporating such gait inconsistency variables into lameness detection models. Further validation of these gait inconsistency variables should be investigated using longitudinal studies where cows developing lameness and recovering from it are monitored daily.


      PubDate: 2015-06-25T13:02:53Z
       
  • Response of pigs divergently selected for residual feed intake to
           experimental infection with the PRRS virus
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): J.R. Dunkelberger , N.J. Boddicker , N.V.L. Serão , J.M. Young , R.R.R. Rowland , J.C.M. Dekkers
      Feed efficiency is of great importance to the swine industry, yet few studies have evaluated the robustness of pigs selected for increased feed efficiency based on residual feed intake (RFI) when challenged with disease. RFI is calculated as the difference between the observed and expected feed intake. The objective of this study was to assess the effect of porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) infection on lines of pigs divergently selected for RFI. Hypothesizing that the more feed efficient low RFI (LRFI) pigs would be more affected by PRRSV-infection, 97 piglets from LRFI and 99 piglets from high RFI (HRFI) selection lines were experimentally infected with the NVSL 97-7985 PRRSV isolate 1 to 3 weeks post-weaning. Pig body weight was recorded weekly and used to calculate average daily gain (ADG). For comparison, ADG was also evaluated on 489 non-challenged LRFI and HRFI pigs housed in a separate facility. Viral load (VL) was quantified as area under the curve for 0–21 days post-infection (dpi) of the log of PCR-based serum viremia. Antibody level was analyzed from serum samples collected at 4, 7, and 11 dpi by PRRS ELISA and MAGPIX assays to quantify PRRSV-specific IgG antibody and total antibody, respectively, during the early stages of PRRSV-infection. There was a tendency for pigs from the LRFI line to have lower VL (P=0.09), greater ADG (P=0.10), and be more likely to survive the PRRSV-challenge (P=0.06) than pigs from the HRFI line. However, joint analysis of challenged and non-challenged pigs showed a significant interaction between RFI line and challenge status (P=0.04), which demonstrated that growth of the LRFI line was less affected by PRRSV-challenge than growth of the HRFI line. Additionally, a significant interaction between RFI line and dpi for the ELISA (P<0.001) and MAGPIX (P=0.007) assays indicated that the increase in antibody levels from 7 to 11 dpi was greater for the LRFI line than for the HRFI line. In conclusion, the line selected for increased feed efficiency based on RFI (LRFI line) had greater growth under challenge and was therefore less affected by the PRRSV-challenge than the line selected for reduced efficiency (HRFI line). This suggests that the pigs selected for reduced RFI were more robust to the viral challenge.


      PubDate: 2015-06-25T13:02:53Z
       
  • Planimetric measurement of floor space covered by fattening rabbits and
           breeding does in different body positions and weight classes
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): Mona Franziska Giersberg , Nicole Kemper , Michaela Fels
      The aim of this study was to measure the floor space that a rabbit occupies due to its physical size and shape. For this purpose the colour contrast planimetric method “KobaPlan” was used which had originally been developed to calculate the surface of chickens. A total of 704 images of fattening rabbits and breeding does were taken from a top view. The rabbits were weighed individually, and photographed digitally in a special planimetric box. In the photo, the number of animal associated pixels was counted by the “KobaPlan” software, and thus the area covered by the animal was calculated. The calculated surfaces of the rabbits were assigned to weight classes which covered a range from 1.0 to 5.5kg. We defined four body postures of rabbits, one sitting position and three different recumbent positions. The mean floor space covered by sitting rabbits at the beginning of the fattening period was 246±34cm², whereas recumbent rabbits covered 294±45cm², 360±51cm² and 338±39cm² in different positions. At the time of slaughter, the covered floor spaces increased to 509±23cm² for sitting rabbits, and to 697±45cm², 724±26cm² and 719±23cm² for recumbent rabbits, respectively. The calculated surface of breeding does with a body weight of 4.5kg was 657±17cm² in sitting position, and 828±7cm², 874±23cm² and 882±14cm² in the different recumbent positions. The heaviest does (5.5kg) covered 739cm² sitting and 1026±27cm² recumbent. There was a linear increase in the surface covered by rabbits in all defined body positions as a function of live weight. Furthermore, sitting rabbits covered significantly less floor space than lying rabbits (P<0.05). It was shown that the colour contrast planimetric method “KobaPlan” provides reliable results regarding the floor space covered by growing rabbits and breeding does. This study is a first step towards an optimization of current rabbit housing regarding individual space requirement, and it represents a useful basis for planning new environmental enrichment structures (e.g. withdrawal areas) in rabbitries.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effect of Mycobacterium avium subsp. paratuberculosis infection status on
           culling and calving difficulty in dairy cattle
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): I. Mato , N. Pesqueira , C. Factor , M.L. Sanjuan , E. Yus , R. Fouz , I. Arnaiz , F. Camino , F.J. Diéguez
      The present paper was designed to assess the effect of Mycobacterium avium subsp. paratuberculosis (MAP) infection status (antibody positive vs antibody negative, as measured by ELISA) on time to culling and calving difficulty in dairy cows. The study was carried out in 8 dairy farms in Galicia (north-west Spain). All of them were taking part in an ongoing paratuberculosis control program, as well as in a dairy herd improvement program. In order to estimate the relation between time to culling and MAP serological status of dairy cows, the present study followed the Andersen–Gill model for survival analysis. Similarly, in order to evaluate the influence on calving difficulty an ordinal logistic regression model was applied. The results indicated that seropositive cows were more likely to be culled due to death/urgent slaughter (hazard ratio=1.88), low productivity (hazard ratio=2.55), infertility (hazard ratio=4.64) and other causes (hazard ratio=1.67). Additionally, the probability of difficulties at calving time was 2.74 times higher for seropositive cows. The estimated effects could determine the economic benefits of a paratuberculosis control program.


      PubDate: 2015-06-25T13:02:53Z
       
  • Lipid mobilization assessment in transition dairy cattle using ultrasound
           image biomarkers
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): C. Strieder-Barboza , A. Zondlak , J. Kayitsinga , A.F.A. Pires , G.A. Contreras
      Excessive lipid mobilization during the transition period of dairy cows predisposes animals to higher disease incidence and reduces lactation performance. Plasma non-esterified fatty acids (NEFA) are used as a marker of lipid mobilization intensity to monitor transition cow management and as a disease risk predictor. NEFA evaluation can be complemented by continuous monitoring of adipose tissue depth reductions during the transition period using ultrasound images of the retroperitoneal (RPAT) and subcutaneous adipose tissue (BFAT) depots. These image biomarkers are easily obtainable and their real time nature offers an important advantage that could help improve transition cow health programs. The objective of this study was to evaluate the use of both RPAT and BFAT ultrasound measurements as quantitative image biomarkers and its association with plasma NEFA. A longitudinal cohort study evaluated adipose image biomarkers in 44 Holstein cows in a commercial dairy herd. Ultrasound examination and blood samples collection were performed at 4 (dry) and 2–3 (close-up) weeks before expected calving date, and at 1 (calving) and 4 (lactation) weeks after parturition. Both RPAT and BFAT depth measurements were significantly lower at parturition and at the lactation samples compared to pre-calving measures and were negatively associated with plasma NEFA. Only BFAT predicted minimum concentrations of plasma NEFA before and after calving. The use BFAT as an image biomarker of lipid mobilization and its risk predictive value in other herds with different management styles requires further investigation.


      PubDate: 2015-06-25T13:02:53Z
       
  • Chromium or l-carnitine supplementation during an aerobic conditioning
           program mildly modified the energy metabolism biomarker response in
           Mangalarga Marchador fillies
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): Mayara Gonçalves Fonseca , Adalgiza Souza Carneiro de Rezende , Lilian de Rezende Jordão , Jessica Lage , Maria Luiza Mendes de Almeida , Juliana Moreira Andrade , Antonio de Queiroz Neto , Guilherme de Camargo Ferraz
      Chromium (Cr) and l-carnitine (LC) are potentially ergogenic substances for athletic horses since they are suggested to increase energy availability for the exercise and postpone the onset of fatigue. The present study aimed to assess the effect of supplementation with chelated chromium or l-carnitine on markers of energy metabolism in Mangalarga Marchador (MM) fillies subjected to marcha treadmill tests. Thirteen fillies were randomly assigned to three groups: Cr (n=4; 10mg/day chelated chromium), LC (n=4; 10g/day l-carnitine), and Control (n=5; no supplementation). The research followed a completely randomized split-split-plot design. Each marcha test represented a plot, each nutritional supplementation group represented a split plot, and each moment in marcha tests represented a split-split-plot. The animals were exercised on the treadmill and automated walker on alternate days from Tuesday to Sunday for 42 days. Treadmill marcha tests took place on days 7 (Test 1), 21 (Test 2), and 42 (Test 3) with 5min of warm-up (1.7ms−1) followed for 30min of marcha (3.5ms−1 and 3% slope). Heart rate (HR), blood lactate (Lac), blood glucose (Glu), and serum triglyceride levels (Trigl) were assessed before exercise and every 5min during the marcha tests. The data underwent repeated measures analysis of variance and the means were compared by Tukey׳s test (P≤0.05). The Cr group had lower HR (P<0.05) at 20min in Test 1; higher Lac (P<0.05) in Test 1 (from 10 to 35min), Test 2 (at 10, 30, and 35min), and Test 3 (at 10min); and higher Glu (P<0.05) in Test 1 (from 20 to 35min) and Test 2 (at 15 and 25min). The LC group had higher (P<0.05) Glu in Test 1 (0min) and lower Trigl (P<0.05) in Test 2 (at 25 and 30min). As early as 21 days into conditioning (Test 2), a reduction (P<0.05) was found on HR, Lac, and Glu, however, Trigl was not affected by the conditioning (P>0.05). The treadmill marcha tests showed a mild effect of chromium or l-carnitine supplementation on the energy metabolism markers of MM fillies subjected to an aerobic conditioning program. LC or Cr supplementation associated with an aerobic conditioning program did not result in superior performance than the conditioning program without supplementation after 42 days. The treadmill aerobic conditioning protocol used in this study seems to improve the physical conditioning of MM fillies after 21 days.


      PubDate: 2015-06-25T13:02:53Z
       
  • Sialic acid content of goat milk during lactation
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): Yasmim Regis Formiga de Sousa , Margarida Angélica da Silva Vasconcelos , Roberto Germano Costa , Clayton Anderson de Azevedo Filho , Emmanuela Prado de Paiva , Rita de Cássia Ramos do Egypto Queiroga
      Sialic acid, which is strategically linked to the surface of glycoproteins, glycolipids and free oligosaccharides, is involved in cellular interaction and communication processes. These processes are related to the main biological functions of sialic acid, which include immune system activation, brain development and protection against pathogens. The present study identified and quantified the classes of sialic acid (Neu5Ac and Neu5Gc) in goat milk during lactation. Forty-eight goat milk samples from twelve Saanen goats in four lactation stages were evaluated. Quantification, separation and identification of the compounds were performed using a chromatographic method. The goat milk contained high concentrations of sialic acids NeuGc and NeuAc, which then declined at the end of lactation. NeuGc had higher concentrations compared to NeuAc in all the lactation phases. Considering these aspects, the presence of these elements in goat milk provides a potential source of bioactive compounds that can be used as functional ingredient in foods.


      PubDate: 2015-06-25T13:02:53Z
       
  • Optimal timing of boar exposure relative to parturition for stimulation of
           lactation oestrus
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): R. Terry , Karen L. Kind , Alice C. Weaver , Paul E. Hughes , William H.E.J. van Wettere
      This study evaluated the effect of full physical boar exposure at different stages of lactation on the incidence of lactation oestrus in both primiparous and multiparous sows. A total of 38 primiparous (PP) and 80 multiparous (MP) sows (parity 2–6; 3.1±0.18) of Large White×Landrace genetics were individually housed in conventional farrowing crates from 1 week before expected farrowing until weaning on day 27.5±0.08 post-parturition. The experiment was designed as a 2×4 factorial, incorporating the two sow parity groups, and boar exposure commencing on one of four days post-farrowing (days 10, 14 and 18 of lactation and weaning). The eight treatments were as follows: PP sows, boar exposure starting on day 10 (n=10), day 14 (n=9), day 18 (n=9) and weaning (n=10); MP sows boar exposure starting on day 10 (n=20), day 14 (n=20), day 18 (n=20) and weaning (n=20). According to treatment, sows were taken daily to a detection mating area where they received 20min of boar exposure and were artificially inseminated at the first observed oestrus. A significant effect of replicate on the incidence of lactation oestrus was found; specifically, the proportion of sows expressing a lactation oestrus was lower in replicate 4 (autumn) than in the other three replicates (winter/spring; 0.15 versus 0.51; P<0.01). In replicate 1–3, a significantly higher proportion of MP compared to PP sows experienced a lactation oestrus (0.63 versus 0.36; P<0.05). Lactation oestrus expression was lower for MP sows starting boar exposure on day 14 compared to day 18 post-partum (0.38 versus 0.79, respectively; P<0.05), but was similar for days 10 and 18 of lactation (0.69 versus 0.79, respectively; P<0.05). Commencing boar exposure on day 18 as opposed to day 10 post-partum significantly reduced the interval from boar exposure to lactation oestrus expression (4.5±0.8 versus 7.7±0.8 days, respectively; P<0.05). Therefore, full physical boar exposure stimulated a high proportion of lactation oestrus in multiparous sows; however, season impacted this expression, and first parity sows are less likely than multiparous sows to express a lactation oestrus. In conclusion, there appears to be no benefit in commencing boar exposure before day 18 post-partum to stimulate a lactation oestrus.


      PubDate: 2015-06-25T13:02:53Z
       
  • Impact of the temperament of Nellore cows on the quality of handling and
           pregnancy rates in fixed-time artificial insemination
    • Abstract: Publication date: July 2015
      Source:Livestock Science, Volume 177
      Author(s): Paola M. Rueda , Aline C. Sant’Anna , Tiago S. Valente , Mateus J.R. Paranhos da Costa
      The aim of this study was to evaluate the effects of temperament on the quality and efficiency of handling and on the pregnancy rate of Nellore cows submitted to a fixed time artificial insemination (FTAI) protocol. Temperament and handling procedures were simultaneously assessed in 798 Nellore cows on the first (d0), ninth (d9) and 11th days (d11) of the FTAI protocol, using the flight speed (FS) and crush score (CS) tests. During the insemination process performed on d11 of the FTAI protocol, the following handling indicators were recorded: rough or overly aggressive handling of the cows by stockpersons (AGGRESSION), accidents (ACCIDENT), time to inseminate (TIME), and the degree of dirtiness on cows’ perineal region (DIRTINESS). There was a significant effect of CS on TIME (P=0.013) and DIRTINESS (P=0.004), while FS tended to affect TIME (P=0.06) and the likelihood of AGGRESSION (P=0.07). Cows subjected to aggressive handling and/or accidents had a greater FS mean than cows that did not face such aversive situations (2.07±1.18 vs. 1.74±0.75m/s, P=0.0003). The chance of pregnancy (expressed in odds ratio) was greater in cows with low FS (OR=1.48) than in cows with high FS (defined as the reference class, with OR=1) (χ 2=3.73, P=0.05), and the low FS group had 10% more pregnant cows than the high FS group (with 52.59% vs. 42.62% pregnant cows, respectively). Pregnant cows had significantly lower FS means relative to non-pregnant cows on d0 (1.79 vs. 2.10m/s, P<0.001), d9 (1.67m/s vs. 1.79m/s, P=0.038) and d11 (1.70m/s vs. 1.90m/s, P=0.004). We conclude that excitable temperament has an effect on the quality and efficiency of handling during FTAI, by increasing the time required for insemination, the dirtiness on cows’ perineal region and the likelihood of aggressive actions by stockpersons. Also, cattle temperament measured by FS reduces the chance of pregnancy in Nellore beef cows.


      PubDate: 2015-06-25T13:02:53Z
       
  • High pasture allowance does not improve animal performance in Supplemented
           dairy cows grazing alfalfa during autumn-winter
    • Abstract: Publication date: Available online 24 June 2015
      Source:Livestock Science
      Author(s): J.L. Danelon , M. Gaggiotti , R. Gallino , R.A. Palladino
      The aim of this study was to assess the effect of three alfalfa pasture herbage allowances on milk yield and composition during autumn-winter grazing season on early autumn calving dairy cows. Eighteen multiparous Holstein dairy cows were assigned to one of three treatments in a 3 × 3 Latin square design: low herbage allowance (14kgDM/cow; LHA), medium herbage allowance (27kgDM/cow; MHA) and high herbage allowance (41kgDM/cow; HHA). Dry matter disappearance was lower at LHA although remained similar between MHA and HHA (P<0.05). However, as herbage allowance (HA) increased, lower grazing efficiencies (as the proportion of material removed) were registered (P<0.05). Total dry matter intake (DMI; kg/d) was also lowest for LHA and similar between the other two treatments (P<0.05). Milk yield, 4%FCM, milk fat (g/kg) and casein (g/kg) tended to increase from LHA to HHA (P<0.10). Cows at LHA tended to loss weight whilst cows at MHA and HHA had a tendency to increase BW according the season progressed (P<0.10). In summary, managing cows at HHA will allow cows to a slightly increase in individual milk production and BW gain but in detriment of herbage utilization and potentially, milk production per hectare.


      PubDate: 2015-06-25T13:02:53Z
       
  • Influence of Trichoderma reesei or Saccharomyces cerevisiae on
           performance, ruminal fermentation, carcass characteristics and Blood
           biochemistry of lambs fed Atriplex nummularia and acacia saligna mixture
    • Abstract: Publication date: Available online 24 June 2015
      Source:Livestock Science
      Author(s): M.H. Ahmed , M.M.Y. Elghandour , A.Z.M. Salem , H.S. Zeweil , A.E. Kholif , A.V. Klieve , A.M.A. Abdelrassol
      The aim of this study was to evaluate whole substitution of Egyptian berseem hay (Trifolium alexandrinum) with a mixture of Atriplex nummularia and Acacia saligna (1:1DM) in the diet of Barki lambs for 70 days. Thirty six lambs (27.0±0.89kg initial BW) were divided into four treatment groups of nine lambs each and fed: the Control group with no substitution (70% concentrate mixture and 30% berseem hay, DM basis), (2) A. nummularia and A. saligna mixture without fungal treatment (treatment group AU), or (3) Trichoderma reesei treated A. nummularia and A. saligna mixture (treatment group AF), or (4) A. nummularia and A. saligna mixture supplemented with Saccharomyces cerevisiae at 0.5g/kg DM of feed (treatment group AS) replaced 100% of berseem hay in the diet. Live-weight change, rumen fermentation parameters, blood chemistry, carcass characteristics and intestinal histology were investigated. Significant (P˂0.05) interactions occurred between diet and period for feed conversion efficiency and blood serum urea. Lambs in the AS treatment consumed less (P˂0.05) feed than lambs in the AF treatment, with no difference between the other treatments (P˃0.05). Lambs fed AF and AU diets had lower (P˂0.05) feed conversion efficiency than lambs fed the AS and Control diets. Lambs fed AF and AS had increased (P˂0.05) volatile fatty acid production compared to Controls. Blood albumin and urea concentrations increased (P˂0.05) with AS treatment compared to lambs in the other treatments, while lambs fed AF had lower (P˂0.05) cholesterol and glucose concentrations compared to the Controls. The AS lambs had the highest (P˂0.05) dressing percentage. Decreased intramuscular weights were obtained with lambs fed halophytes compared to Control. Histology of the ileum, sub mucosa and Peyer’s patches were normal in all lambs. In conclusion, untreated halophyte mixtures of A. nummularia and A. saligna (at 1:1 DM) can be substituted for berseem hay without negative effects on performance while treatment with S. cerevisiae may improve performance and- like T. reesei change certain biochemical responses.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effect of rearing systems and diets composition on the survival of
           probiotic bifidobacteria in the digestive tract of calves
    • Abstract: Publication date: Available online 24 June 2015
      Source:Livestock Science
      Author(s): Věra Bunešová , Eva Vlková , Martina Geigerová , Vojtěch Rada
      The effect of rearing systems and diets composition on the survival of administered probiotic bifidobacteria in the digestive tract of calves was examined. Two bifidobacteria strains of calf origin with suitable physiological properties, which were identified as Bifidobacterium animalis ssp. animalis and B. longum ssp. suis, were administered to 8 Charolais calves reared in an extensive farming system fed the full-milk diet and 8 Holstein calves from an intensive system fed the combined diet. Skim-milk fermented by rifampicin-resistant bifidobacteria variants of the B. animalis ssp. animalis and B. longum ssp. suis strains were administered once to 2-day-old calves. Survival of the administered bifidobacteria and the numbers of other bacterial groups in faecal samples was monitored by culturing. Probiotics administered to Charolais calves survived at higher counts than 107 CFU/g in the digestive tract for at least 26 days. Significantly lower bifidobacteria survival rate was observed in the Holstein calves. Three days after administration of bifidobacteria were detected in counts 107 CFU/g; however, their numbers rapidly dropped reaching a value of about 102 CFU/g on day 26 after administration. Bifidobacteria dominated the faecal flora of 5-day-old calves in both groups. Significantly higher lactobacilli counts were detected in the Charolais calves than in the Holstein calves. Our results showed that administration of probiotics is more effective in calves fed the full-milk diet reared in an extensive farming system. To achieve a probiotic effect in intensively reared animals, repeated application would probably be required, because the tested bifidobacteria were not able to colonise the digestive tract of calves fed the combined diet from an intensive rearing system.


      PubDate: 2015-06-25T13:02:53Z
       
  • Genetic parameters and predictions for direct and maternal growth traits
           in a multibreed Angus-Brahman cattle population using genomic-polygenic
           and polygenic models
    • Abstract: Publication date: Available online 24 June 2015
      Source:Livestock Science
      Author(s): M.A. Elzo , M.G. Thomas , D.D. Johnson , C.A. Martinez , G.C. Lamb , D.O. Rae , J.G. Wasdin , J.D. Driver
      The objectives of this research were to compare variance components, genetic parameters, and EBV rankings for birth weight (BW) direct and maternal, weaning weight (WW) direct and maternal, and postweaning gain from 205 d to 365d (PWG) direct using three genomic-polygenic and one polygenic model representing four plausible beef cattle genetic evaluation scenarios for growth traits under subtropical conditions in the US southern region. In addition, EBV trends as percentage Brahman increased from 0% to 100% were evaluated for each trait and model. The dataset included 5,264 animals from a multibreed Angus-Brahman population born from 1987 to 2013. Genomic-polygenic models 1 (GP1; pedigree relationships for all animals; genomic relationships for genotyped animals), 2 (GP2; pedigree relationships for non-genotyped animals; genomic relationships for genotyped animals), and 3 (GP3; no pedigree relationships; genomic relationships for genotyped animals) used actual and imputed genotypes from 46,768 SNP markers. Variance components and genetic parameters were estimated using REML procedures. Variance component and genetic parameter estimates from GP1 were the most similar to those from the polygenic model, followed by those from GP2, and the least similar (especially for maternal traits) were those from GP3. Similarly, the highest rank correlations were those between animal EBV from the polygenic model and GP1, followed by those between animal EBV from GP1 and GP2 and between the polygenic model and GP2. Model GP3 performed poorly for maternal traits due to ignoring calf-dam relationships. These results indicated that the polygenic model and genomic-polygenic model 1 should be preferred. However, high genotyping costs still make the polygenic model preferable for commercial beef cattle operations. Brahman animals tended to have higher EBV for BW direct and WW direct, and lower EBV for PWG direct, BW maternal, and WW maternal. However, low regression coefficients for EBV on Brahman fraction ensured that high, medium, and low EBV animals from all breed compositions existed in this multibreed population.


      PubDate: 2015-06-25T13:02:53Z
       
  • Assessment of finishing beef cattle mortality in a sustainable farming
           perspective
    • Abstract: Publication date: Available online 23 June 2015
      Source:Livestock Science
      Author(s): Clelia Rumor , Marta Brscic , Barbara Contiero , Giulio Cozzi , Flaviana Gottardo
      Cattle mortality has a relevant economic and environmental impact but it has been scarcely investigated in finishing beef cattle farms. Aim of this study was to investigate mortality rate in 45 intensive beef cattle farms located in North-Eastern Italy from 2010 to 2013 and to evaluate potential risk factors affecting it. Information from the Italian National Cattle Movement database, as source of mortality data, were crossed with descriptors of barn features and farm management gathered by an on-farm survey to identify factors influencing mortality at farm level, which could be of direct utility for the farmers to reduce cattle losses. Results showed an overall average mortality rate in the 4-year period of 1.4% ranging from 0% to 5.3%. Mortality occurred within the first half of the finishing period, on average 3.4 months after the arrival at the fattening unit. A multivariate regression model showed that mortality was affected by breed (P=0.020) and by floor type as trend (P=0.083). Pure Charolaise (Odds ratio=1.70, 95% Confidence interval=1.11-2.59; P<0.005 and Limousine breeds (Odds ratio=1.96, 95% Confidence interval=1.26–3.05; P<0.005) showed higher odds for mortality compared to other beef breeds or crosses. Bulls housed on fully slatted floor showed higher odds compared to those on deep litter (Odds ratio=1.45, 95% Confidence interval=1.01-2.08; P<0.005). Season at arrival affected mortality (P=0.013), with summer (Odds ratio=1.45, 95% Confidence interval=1.14–1.84; P<0.005) and autumn (Odds ratio=1.74, 95% Confidence interval=1.27–2.38; P<0.005) being the most critical seasons. Differently from expected, space allowance and barn features such as presence/absence of roof insulation and/or ventilation devices as well as the managerial choice of separating or not newly arrived bulls in a dedicated receiving area for quarantine did not affect mortality. Based on findings from this study, it could be concluded that the avoidance of rearing specialized French beef breeds, of using fully slatted floor and of importing young cattle during warm seasons could be considered as preventive measures to reduce the risk of mortality in intensive beef cattle farms.


      PubDate: 2015-06-25T13:02:53Z
       
  • Production and environmental impact of dairy cattle production in Denmark
           1900-2010
    • Abstract: Publication date: Available online 23 June 2015
      Source:Livestock Science
      Author(s): Troels Kristensen , Ole Aaes , Martin Riis Weisbjerg
      Cattle production during the last century has changed dramatically in Western Europe, including Denmark, with a steady increase in production per animal and in herd and farm size. The effect of these changes on total production, herd efficiency, surplus of nitrogen (N) at herd and farm level and emission of greenhouse gasses (GHG) per kg product has been evaluated for the Danish dairy cattle sector based on historic information. Typical farms representing the average situation for Danish dairy cattle farms and land required for feed supply was modelled for the situation in: A) 1920 – representing a local-based production, B) 1950 – representing a period with emerging mechanization and introduction of new technologies and a more global market, C) 1980 – representing a period with heavy use of external resources like fertilizer and feed protein and D) 2010 – today with focus on balancing production and risk of environmental damage. In A, B and C, other livestock such as pigs and hens also played a role, while the dairy farm in 2010 only had cattle. In 1920 and 1950 the farm was based on 7-8 dairy cows producing typically 1800-3400kg energy-corrected milk (ECM) per cow annually and fed primarily on pasture and hay, only to a limited extent supplemented with imported protein. In 1980 the herd size had increased to 20 dairy cows producing 5000kg ECM each, and feeding was with silage instead of hay, but still included grazing and there was a larger proportion of imported feed. In 2010 the herd had increased to 134 dairy cows producing 9000kg ECM per cow and fed indoors all year. During this period net energy used for milk and meat in % of total intake and land use per 1000kg of milk has steadily decreased as a consequence of higher milk yield per cow and higher yields of forage per ha. In opposition, the utilization of N in the herd, while increasing from 1920 to 1950 and to 2010 showed a drop in the 1980 system, where also the environmental N surplus per ha farmland was highest (40; 65; 226; 148kg N per ha farmland in the respective periods). The lower N efficiency in 1980 also resulted in an increased GHG emission per kg milk than in the preceding and following periods (2.23; 1.38; 1.94; 1.20kg CO2-eq. per kg ECM in the respective periods). It is concluded that the biological and technical development has made it possible to reduce the environmental load of dairy production significantly, but that this requires a strong focus on nitrogen management at the farm level and production efficiency in the herd.


      PubDate: 2015-06-25T13:02:53Z
       
  • Methods for reduction of water soluble carbohydrate content in grass
           forages for horses
    • Abstract: Publication date: Available online 17 June 2015
      Source:Livestock Science
      Author(s): C.E. Müller , K. Nostell , J. Bröjer
      A large number of factors influence water soluble carbohydrate (WSC) concentration in forages. Four of these were studied; effect of conservation method (silage, haylage, hay); effect of using bacterial inoculants in silage and haylage; effect of storage time; and effect of soaking. Grass forage was harvested as silage (400g dry matter (DM)/kg) and haylage (600gDM/kg) in laboratory silos and as hay (840gDM/kg). Silage and haylage were preserved with and without a bacterial inoculant. All forages were sampled at 3, 6, 12 and 18 months of storage. Forages stored for 3 and 12 months were soaked in water for 12 and 24h to evaluate soaking as a method to reduce WSC concentration. Concentrations of glucose, fructose, sucrose and fructans were analysed using an enzymatic-spectrophotometric method and total WSC concentration calculated as the sum of these. Conservation method influenced concentration of WSC and its components, as silage had lower content of glucose, fructose and WSC compared to haylage and hay; and silage and haylage contained less sucrose and fructans compared to hay (P<0.001). Use of inoculants in haylage and silage resulted in lower fructose concentration in silage (P=0.03) but not in haylage. No consistent effects of storage time on concentration of WSC and its components were present. Soaking for 12h reduced concentration of fructose and WSC in silage to approximately half of the initial concentration before soaking (P=0.001). For haylage, soaking for 12h resulted in approximately half of the concentration of initial glucose, fructose and WSC (P<0.001), but no further reduction in these components was present after 24h soaking time. For hay, soaking for 12h resulted in 50% of glucose, 70% of fructose, 15% of sucrose and 40% of fructan concentrations compared to initial contents (P<0.02). Soaking hay for 24h resulted in further reduction of glucose and WSC concentrations (P<0.001). Concentration of WSC was lower in silage compared to haylage and hay due to the utilization of WSC components by lactic acid bacteria during ensiling. Concentration of WSC in silage before soaking (24g/kg DM) was also lower than in hay after soaking for 24h (38g/kg DM), meaning thatpreserving forage as silage was more effective in reducing WSC concentration than soaking of hay. If the goal is to produce forage with low WSC concentration, preservation as silage should be preferred over hay-making.


      PubDate: 2015-06-25T13:02:53Z
       
  • Influence of genotype and feeding strategy on pig performance, plasma
           concentrations of micro nutrients, immune responses and faecal microbiota
           composition of growing-finishing pigs in a forage-based system
    • Abstract: Publication date: Available online 15 June 2015
      Source:Livestock Science
      Author(s): A.G. Kongsted , J.V. Nørgaard , S.K. Jensen , C. Lauridsen , H.R. Juul-Madsen , L.R. Norup , R.M. Engberg , K. Horsted , J.E. Hermansen
      In free-range pig production it is important to reduce the input of nutrients from supplementary feed to reduce nutrient leaching and improve the resource efficiency of the system. A promising development might be to encourage foraging behaviour of the pigs. However, very little is known about pigs' ability to take advantage of direct foraging to cover their nutritional needs and how this interacts with breed and affects robustness. Pig performance, plasma concentration of micro nutrients, immune response and faecal microbiota composition were studied in 72 growing pigs (34 to 105kg live weight) of either a traditional (Tamworth×(Landrace×Yorkshire)) or a ‘modern’ crossbreed (Duroc×(Landrace×Yorkshire)) fed a pelleted diet as supplementary feed either according to recommendations (NORM), or restrictedly with (RES+) or without (RES–) a supplementary vitamin and mineral mixture. The pigs ‘strip grazed’ a diverse pasture with a grass–clover mixture and forage herbs (338m2 pig–1) and root chicory (34m2 pig–1). The results revealed that a 33% reduction in feed allowance of a pelleted diet reduced daily gain with up to 25% but improved conversion of supplementary feed into live weight with up to 15%. There were no significant differences in pig performance between RES+ and RES–. The two breed combinations responded similarly to the reduction in feed allowance with regard to growth performance and feed conversion. Across feeding strategy, the traditional crossbred had 20% lower daily weight gain and used 25% more supplementary feed per kg live weight gain compared to the ‘modern’ crossbreed. Omitting a mineral and vitamin premix to the diet had no consistent effects on plasma concentration of minerals but the plasma concentration of α-tocopherol and retinol were significant lower in RES– pigs compared to RES+ and NORM pigs. Plasma 25-D3 was significant lower in October than in September. The immune response and microbial composition showed few and inconsistent differences between treatments. In conclusion, this study indicated that direct foraging in a diverse range area contributed significantly to the nutritional supply of pigs fed restrictedly with supplementary feed. There are indications that the mineral content of the premix is not needed in a forage-based free-range system but cautious need to be taken with regards to the vitamin A, D, E supply.


      PubDate: 2015-06-25T13:02:53Z
       
  • Genetic parameters of type traits in two strains of dual purpose
           autochthonous Valdostana cattle
    • Abstract: Publication date: Available online 12 June 2015
      Source:Livestock Science
      Author(s): Serena Mazza , Cristina Sartori , Roberto Mantovani
      The main objectives of this study were (i) to investigate the best fitting model for the genetic analysis of type traits and (ii) to estimate the genetic parameters of 4 composite (body size, muscularity, body shape, and udder) and 22 individual type traits between and within the two strains of the Valdostana dual purpose breed: the Aosta Red Pied (ARP; n=25,183 records) and the Aosta Black Pied and Chestnut (ABP-CHES; n=14,701 records). All type traits were scored from 2000 to 2012 on primiparous cows using a 1 to 5-point scale system. A model comparison was undertaken by considering the Akaike Information Criterion values obtained from the analysis, producing a final model that took into account the effects of herd-year-classifier, days in milk, age at calving as fixed and the animal additive genetic effect as random. Heritability estimates obtained through single trait animal model analysis varied from 0.03 for thinness (in both strains) to 0.32 (ARP) and 0.29 (ABP-CHES) for stature. Medium-low heritability estimates were obtained for individual muscularity traits (0.22 for ARP and 0.13 for ABP-CHES), and for individual udder type traits (0.12 on average in both Valdostana strains). The highest genetic correlations between composite traits were for muscularity with body shape in both Valdostana strains (0.55 for ARP and 0.52 for ABP-CHES). Different and opposite values of genetic correlations were found for the composite body shape and the composite udder traits (0.13 for ARP and –0.25 for ABP-CHES; P<0.01), probably due to the different breeding purposes set up for the two Valdostana strains. Regarding the individual type traits, for the ARP strain the highest genetic correlation was 0.97 (between thigh, buttocks side and rear view), whereas for the ABP-CHES strain it was 0.98 (between stature and body length), meaning that improving one trait of each pair led to a positive variation in the other. Most of the genetic correlations between the individual muscularity traits and the individual udder traits were negative, especially those involving udder volume (from –0.19 to –0.42 in ARP, and from –0.17 to –0.41 in ABP-CHES; P<0.01), indicating a substantial antagonistic situation of type traits related to dairy and beef traits. In conclusion, the selection for the dual purpose in local breeds such as in Valdostana cattle implies a thorough consideration of opposite morphological traits.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effect of fish meal and oil on hormone profile and reproductive variables
           in ewes inseminated by laparoscopy
    • Abstract: Publication date: Available online 11 June 2015
      Source:Livestock Science
      Author(s): R. Nieto , M.T. Sánchez-Torres , O. Mejía , J.L. Figueroa , L. Olivares , J.G. Peralta , J.L. Cordero , P. Molina , M. Cárdenas
      The addition of n-3 polyunsaturated fatty acids (PUFA) to the diet of ruminants can benefit the reproductive process in the female. The current study was conducted to assess the effect of a short period of feeding a diet that included fish meal and oil on the progesterone (P4) and insulin (INS) profile, and on reproductive variables including estrous onset, pregnancy and prolificacy in virgin ewes artificially inseminated by laparoscopy (AIL). Forty-two Dorset ewes were assigned into two experimental groups: These groups were no supplementation (CON; n=21) and a group supplemented with fish meal and oil (4 and 0.8%; FMO; n=21). Ewes were fed the experimental diets for 15 days, beginning four days before inserting sponges for estrus synchronization and ending the day the vaginal sponges were removed. Each ewe received 0.8kg d−1 feed in individual pens. Ewes were pre-synchronized with prostaglandin F2α and later synchronized with chronolone sponges for 11 days. When sponges were removed, the ewes received 200 IU of eCG. The AIL began 48h after sponge removal and estrus detection. The time of estrus onset was different among groups (P<0.05; CON: 35.1±2.1; FMO: 41.0±1.8h). No differences were found in P4 (FMO: 3.8±1.2; CON: 3.5±1.4ngmL−1) or INS concentrations in serum (FMO: 0.12±0.02; CON: 0.13±0.03ngmL−1). Adding fish meal and oil to the diet did not affect pregnancy percentage (FMO: 52%; CON: 55%), but it did affect the prolificacy index (FMO: 1.63; CON: 1.25) (P<0.05). It was concluded that the addition of fish meal and oil to the diet of virgin ewes over a short period time delayed onset of estrus and enhanced prolificacy.


      PubDate: 2015-06-25T13:02:53Z
       
  • Growth and development of the Lusitano horse managed on grazing systems
    • Abstract: Publication date: Available online 11 June 2015
      Source:Livestock Science
      Author(s): M.J. Fradinho , R.J.B. Bessa , G. Ferreira-Dias , R.M. Caldeira
      The main objective of the present study was to characterize the growth patterns of Lusitano horse managed on grazing systems from birth to 42 month of age. A total of 4759 records for body weight (BW), withers height (WH), girth (G) and cannon circumference (CC) were obtained from 121 Lusitano foals (62 colts and 59 fillies) born and raised at four stud-farms. Data were regularly collected between birth and 42 months of age, when foals began to be ridden. Several sigmoid growth functions were adjusted using the NLIN procedures of SAS. The Richards equation  y = A ( 1 - b · exp ( - k t ) ) M was chosen for further analysis because it was the best fit model for all the variables. Growth rates (ADG, kg/d or cm/d) were obtained from the first derivative of the equations. The influence of season was examined and the effect of gender was tested. The mean mature BW was 552.4±22.0kg and the average mature sizes were 158.6±0.8cm, 197.8±3.6cm and 19.9±0.2cm, respectively for WH, G and CC. Proportions (%) of mature BW at 6, 12, 18, 24, 30, 36 and 42 months of age, according to the Lusitano breed standard were, respectively, 42, 58, 69, 77, 84, 89 and 93%. The proportions (%) of mature WH for the same ages were 82, 88, 92, 94, 95, 96 and 97%. Concerning BW, Lusitano showed a slower growth rate, comparable with the moderate growth proposed for other sport breeds. In contrast, the WH growth rate was similar to those presented by early maturing breeds. A clear sexual dimorphism was observed on all variables, with higher maturity values for males (P<0.0001). The present study provides a comprehensive overview on growth patterns of the Lusitano horse managed in grazing systems under Mediterranean climate conditions. Further studies with controlled feeding levels should be done in order to verify the potential growth response of this breed.


      PubDate: 2015-06-25T13:02:53Z
       
  • Pilot study on work load management and feed intake time when feeding
           horses with small mesh haynets
    • Abstract: Publication date: Available online 11 June 2015
      Source:Livestock Science
      Author(s): K. Morgan , L. Kjellberg , L. Karlsson Budde , E. Kjell , M. Ryman
      Horses are by nature herbivores and graze during the main part of the day. For stabled horses the feeding rations are often restricted and it would be preferred to develop a feeding system that allows long feed intake times. A possible way to lengthen the feed intake time is to hamper the availability of the forage by using a small-mesh haynet. The study had two aims concerning feeding horses with small-mesh haynets; first to investigate how the stable staff’s work load was affected and second to study the horse’s feed intake time. Two parallel studies were carried out at the Swedish National Equestrian Centre Strömsholm. In both studies four split-up portions daily were used as control management. The first study on work load measured the time of feeding routines using 14 horses fed with small-mesh haynets once a day and 17 horses in the control management. The second study focused on the feed intake time using a cross-over design where four horses were filmed during four consecutive days in each feeding system; feeding forage once a day in small-mesh haynets (mesh size 3×3cm) compared to control management. The data were statistically analysed and the level of significance was set to p<0.05. The horses remained their body condition and no colic occurred. The daily working time per horse and day for feeding management was significantly longer (p<0.001) when using small-mesh haynets (mean 6min 34s) compared to the control group (mean 2min 53s). The total feed intake time increased in three out of four horses (by 50%–67%). We concluded that the working time for the small-mesh haynets was significantly longer compared to control management with weighing into individual feeding portions administrated three times a day. The feed intake time increased in three of the four horses with the small-mesh haynets and individual variations were observed.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effects of feruloyl esterase, non-starch polysaccharide degrading enzymes,
           phytase, and their combinations on in vitro degradation of rice bran and
           nutrient digestibility of rice bran based diets in adult cockerels
    • Abstract: Publication date: Available online 11 June 2015
      Source:Livestock Science
      Author(s): Q. Liu , D.Y. Zhou , L. Chen , R.Q. Dong , S. Zhuang
      The objective of this research was to evaluate the feasibility of improving the nutritive value of rice bran used as poultry feed ingredient by the combination of feruloyl esterase (FAE), non-starch polysaccharide degrading enzyme cocktail (non-starch polysaccharide enzyme containing xylanase, cellulase, and β-galactosidase, NSPase), and phytase. After analyzing the phenolic acid profile of defatted rice bran (DFRB), an in vitro degradation experiment, and an in vivo metabolism assay were conducted. The effects of FAE, NSPase, and phytase were assessed in a 2×2×2 factorial in vitro experiment using DFRB as substrate. Feruloyl esterase, NSPase, and their combination increased the release of ferulic acid from DFRB (P<0.001). Non-starch polysaccharide degrading enzyme cocktail increased reducing sugar production (P<0.001). Phytase addition increased the dry matter disappearance (P<0.001), but resulted in a reduction in the levels of ferulic acid and reducing sugar released when combined with FAE and NSPase, respectively. In in vivo experiment, 40 adult cockerels (BW=2.2±0.1kg) were randomly divided into 5 treatments with 8 individual cockerels per treatment. Cockerels in 1 treatment were force-fed 1 of full-fat rice bran based diets [without enzyme supplementation (RB), with NSPase (RBN), NSPase+FAE (RBNF), NSPase+phytase (RBNP), or NSPase+FAE+phytase (RBNFP) addition, respectively]. Enzyme additions improved the nutrient digestibility of rice bran. The greatest enhancements in digestibility coefficients of dry matter (P=0.036), gross energy (P<0.001), ether extract (P<0.001), and neutral detergent fiber (P=0.01) were found in the RBNF and RBNFP diets. The apparent metabolizable energy of full-fat rice bran based diets increased from 12.05 (RB diet) to 13.05 (RBNF diet), and, then, to 13.13MJ/kg (RBNFP diet). In conclusion, combining FAE with NSPase and phytase improved both in vitro dry matter degradation and ferulic acid release, and in vivo nutrient digestibility of rice bran based diets. It showed a high potential in improving the use of rice bran as poultry feed.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effects of grape seed procyanidins on growth performance, immune function
           and antioxidant capacity in weaned piglets
    • Abstract: Publication date: Available online 9 June 2015
      Source:Livestock Science
      Author(s): Ruirong Hao , Qinghong Li , Jiaqi Zhao , Huifeng Li , Weiwei Wang , Junjie Gao
      The trial was conducted to investigate effects of grape seed procyanidins (GSP) on growth performance, immune function and antioxidant capacity in weaned piglets. A total of 160 Duroc×Landrace×Yorkshine piglets weaned at 21 days of age (body weight, 6.99±0.11kg) were randomly assigned to one of the five treatment groups with 4 replicate pens per group and 8 piglets per pen. The treatments included control group (fed a basal corn–soybean meal diet, BD), antibiotics group (BD+20mg/kg of flavomycin+100mg/kg of aureomycin), and three different GSP level groups (BD+50, 100, 150mg/kg GSP respectively). The trial lasted 28 days. Diarrhea scores were recorded daily, and the average daily gain (ADG), average daily feed intake (ADFI) and feed/gain ratio (F:G) were calculated. Blood samples were collected on d 14 and 28 for the measurement of serum immune parameters and antioxidant indices. Dietary GSP or antibiotics supplementation did not exert significant effects on ADG, ADFI and F/G during overall experimental period. As compared with the control group, supplementation with antibiotics or different levels of GSP decreased the diarrhea incidences in piglets significantly (P<0.05). Pigs offered diets supplemented with GSP at doses of 100 or 150mg/kg generated higher (P<0.05) serum immunoglobulin (Ig) G, IgM, complement 4 (C4) and interleukin-2 (IL-2) concentrations, produced stronger (P<0.05) serum total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities and lower serum malondialdehyde (MDA) content than those fed basal diet or antibiotics diet. In conclusion, administration of GSP in weaned piglets diet had no effect on the growth performance during the whole experiment. However, the beneficial effects on diarrhea incidences, immune responses and antioxidant abilities suggested that GSP has a positive role in weaned piglets.


      PubDate: 2015-06-25T13:02:53Z
       
  • Addition of inulin, alfalfa and citrus pulp in diets for piglets:
           Influence on nutritional and faecal parameters, intestinal organs, and
           colonic fermentation and bacterial populations
    • Abstract: Publication date: Available online 9 June 2015
      Source:Livestock Science
      Author(s): Sebastián Brambillasca , Pablo Zunino , Cecilia Cajarville
      The effects of the inclusion of inulin, fresh alfalfa and fresh citrus pulp in diets for piglets on intake, nutritional and faecal parameters, digestive tract size, fermentation kinetics and colonic microbial populations was evaluated. Twenty-four cross-breed piglets (initial BW: 9.75±1.63kg) in a randomized complete block design were housed in metabolic cages and assigned to one of 4 treatments: 100% corn and soybean meal control diet (CON), 97% CON+3% inulin (INU), 95.5% CON+4.5% fresh alfalfa (ALF) and 95.5% CON+4.5% fresh citrus pulp (CIT). The experiment consisted of a 12 d adaptation period followed by 12 d for samples collection. The last 2 days of the experiment all animals were euthanized, the digestive tract of each animal was removed and an individual sample of colonic digesta was collected. Feed intake tended to be lower in the fibre supplemented groups (P=0.098), and was lower in ALF than in CIT (P=0.026). Groups receiving fibres tended to excrete more faeces (P=0.088), evacuated softer faeces (P=0.041) and presented a lower digestibility of CP (P=0.003). Retention of N was higher in the CON group than in fibre containing diets (P=0.009), and lower for ALF than for CIT (P=0.034). Colonic pH was lower in CIT and ALF treatments than in INU (P=0.016), in vitro gas volume was higher in the fibre-supplemented groups than in CON (P=0.048), but no differences between colonic bacterial counts were noticed among treatments. From the data obtained we conclude that the addition of fresh alfalfa and citrus pulp produce some beneficial effects in terms of promoting an increase in the hindgut fermentation, but negative aspects related to poorer nutrients absorption and N utilization can limit the usage of these fibrous sources.


      PubDate: 2015-06-25T13:02:53Z
       
  • Animal performance, carcass characteristics and beef fatty acid profile of
           grazing steers supplemented with corn grain and increasing amounts of
           flaxseed at two animal weights during finishing
    • Abstract: Publication date: Available online 9 June 2015
      Source:Livestock Science
      Author(s): L. Pouzo , N. Fanego , F.J Santini , A. Descalzo , E. Pavan
      The objective of this study was to determine (1) the effects of increasing flaxseed addition to the corn grain supplemented at finishing to grazing steers on animal performance, carcass characteristics and longissimus muscle (LM) fatty acid profile, and (2) whether dietary treatments effects are affected by animal body weight (BW) at supplementation. Forty eight steers were assigned to eight treatment combinations defined by four dietary treatments (CNTRL, no supplement; FLAX-0, 0.7% BW of cracked corn grain; FLAX-1 and FLAX-2, FLAX-0 plus 0.125% and 0.250% BW of unprocessed flaxseed, respectively) and by two animal BW treatments generated by supplementing steer in early spring (EARLY) or late spring (LATE). Steers assigned to EARLY received their dietary treatment when reaching 366±27.3kg BW (August, 3rd) and those assigned to LATE when reaching 458±42.8kg (October, 10th). After 70d on trial, carcass data and LM samples (12th rib region) were collected for fatty acid (FA) analysis. Total DMI was greater in supplemented treatments (FLAX-0, FLAX-1 and FLAX-2) than in CNTRL, with no flaxseed level effect. Dietary treatment effects on performance and carcass characteristics were not affected by BW treatments. Increasing flaxseed supplementation linearly increased subcutaneous fat thickness; whereas increasing BW at initiation of supplementation decreased average daily again, but increase final BW, hot carcass weight, and LM total fatty acid content. Animal BW at initiation of supplementation affected dietary treatments effects on LM n-6/n-3 ratio; ratio was highest in FLAX-0 and lowest in CNTRL and FLAX-2 in both BW treatments; did not differ between BW treatments in CNTRL and in FLAX-2, but was greater in EARLY than in LATE in FLAX-0 and FLAX-1. Trans-vaccenic acid proportion was greater in CNTRL than in supplemented treatments, but was not affected by flaxseed level; similar trend was observed for CLA cis-9, trans-11 proportion. Linolenic acid proportion did not differ between CNTRL and supplemented treatments, but was linearly increased with flaxseed level. Fatty acids changes with increasing animal BW at supplementation were associated with the increased in total muscle fatty acid content; total and individual polyunsaturated fatty acids were lower in LATE than in EARLY, whereas trans-vaccenic acid and CLA cis-9, trans-11 were greater. Adding flaxseed to the corn grain supplemented increase subcutaneous fat thickness of grazing steers without negatively affecting fatty acid profile, except for a reduction in trans-vaccenic acid proportion. Therefore, adding flaxseed to the corn supplemented to grazing steers increases carcass fatness while reducing the negative effect of corn supplementation on LM n-6/n-3 ratio but not on trans-vaccenic acid. Increasing BW at supplementation reduces supplementation effects on LM n-6/n-3 ratio.


      PubDate: 2015-06-25T13:02:53Z
       
  • Impact on digestibility, and blood and fecal parameters of replacing wheat
           bran with corn gluten meal in concentrate of adult horses
    • Abstract: Publication date: Available online 8 June 2015
      Source:Livestock Science
      Author(s): G.F. Correa , O.C.A. Nascimento , T.P. Mota , G.O. Hespanholo , C.G. Moreira , M.L. Menezes , I. Vervuert , J.C.C. Balieiro , I.C.S. Bueno , R.A. Brandi
      The objective of this study was to assess the impact of replacing wheat bran with increasing levels (10%, 20% and 30%) of corn gluten meal 21 (CGM 21) in the concentrate of adult horses. Four adult horses were used in a 4×4 Latin square designed experiment. Total tract apparent digestibility (TTAD), and selected fecal (pH, buffering capacity, concentration of short-chain fatty acids) and blood (glucose, cholesterol, triglycerides) parameters were used as response parameters. The results showed that replacing wheat bran with CGM 21 did not affect (p>0.05) TTAD, fecal pH, fecal buffering capacity, fecal concentration of short chain fatty acids or blood glucose. However, blood cholesterol and triglycerides decreased (p<0.05) with increasing levels of CGM 21 in the concentrate.


      PubDate: 2015-06-25T13:02:53Z
       
  • Ammonia and amino acids modulates enzymes associated with ammonia
           assimilation pathway by ruminal microbiota in vitro
    • Abstract: Publication date: Available online 6 June 2015
      Source:Livestock Science
      Author(s): Pengpeng Wang , Zhiliang Tan , Leluo Guan , Shaoxun Tang , Chuanshe Zhou , Xuefeng Han , Jinhe Kang , Zhixiong He
      The objective of this study was to evaluate the effects of ammonia and amino acids (AA) supplementation on activities of ruminal enzymes involved in ammonia assimilation. In addition, the temporal changes of ruminal bacterial populations and enzyme activities during in vitro incubation were investigated. Rumen fluid from four ruminally fistulated goats was used in a 3×3 factorial arrangement of treatments with ammonia equivalent to 1, 4, and 15mM ammonium chloride (NH4Cl), and with an added AA mixture (containing 992g casein acid hydrolysate plus 1.4g l-cysteine plus 8.68g l-tryptophan) at 0, 1, and 15.5g/L in the in vitro culture solution. Both ammonia and AA supplementation increased (P<0.01) ammonia–nitrogen and volatile fatty acids concentrations. There was an interaction (P=0.04) between NH4Cl and AA concentrations on the yield of microbial crude protein. The population of total bacteria was dose-dependent with ammonia concentration (P=0.01), but was increased following AA increment (P<0.01). Supplement of AA activated (P<0.01) enzymes of glutamine synthetase (GS), glutamate synthetase (GOGAT), and glutamate dehydrogenase (GDH), but inhibited (P<0.01) enzyme of alanine dehydrogenase (ADH), all of which were important in ammonia assimilation for ruminal microbiota. And all these four enzymes were more active at the later period of process. The GDH activity was significantly associated with the population of Prevotella ruminicola (r=0.66; P<0.01), while the correlations between ADH activity and Fibrobacter succinogenes (r=0.41, P=0.04) or Butyrivibrio fibrisolvens (r=0.45, P=0.02) were not strong. Enzymes of GS, GOGAT and GDH had strong correlations (P<0.01) with yield of MCP. These results suggest that AA supplementation alters fermentation pattern, and stimulates the GS–GOGAT and GDH pathways of ammonia assimilation.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effects of Lactobacillus brevis preparation on growth performance, fecal
           microflora and serum profile in weaned pigs
    • Abstract: Publication date: Available online 5 June 2015
      Source:Livestock Science
      Author(s): H. Liu , H.F. Ji , D.Y. Zhang , S.X. Wang , J. Wang , D.C. Shan , Y.M. Wang
      This study was conducted to evaluate the effects of Lactobacillus brevis ZLB004 on growth performance, fecal microflora, and serum profile in weaned pigs. A total of 144 weaned pigs (Duroc×Yorkshire×Landrace) with an average initial body weight of 15.60±0.13kg were randomly assigned to 3 treatments, with 4 replicate pen per treatment and 12 pigs per pen. Pigs were fed the basal diet supplemented with 0, 0.4, and 0.8g/kg of L. brevis ZLB004. All pigs were given free access to feed and water for 30d. The results showed that pigs fed diets with L. brevis ZLB004 increased average daily gain, average daily feed intake, and gain to feed ratio (P=0.026, 0.031, and 0.022 respectively), while decreased diarrhea incidence (P=0.044) compared with the control group. On d 30, dietary L. brevis ZLB004 increased lactobacillus populations (P=0.001), reduced fecal coliform populations (P=0.022). Supplemental L. brevis ZLB004 increased serum interferon-γ and total protein concentrations (P=0.024 and 0.044, respectively), while decreased serum haptoglobin and blood urea nitrogen (P=0.014 and 0.040, respectively). The results showed that L. brevis ZLB004 had beneficial effects on the improvement of intestinal microflora balance, immunity, and growth performance of weaned pigs.


      PubDate: 2015-06-25T13:02:53Z
       
  • Nordic dairy cow model Karoline in predicting methane emissions: 1. Model
           description and sensitivity analysis
    • Abstract: Publication date: Available online 5 June 2015
      Source:Livestock Science
      Author(s): Pekka Huhtanen , Mohammad Ramin , Peter Udén
      Decreasing methane (CH4) emissions is necessary both environmentally, as CH4 has a strong greenhouse gas effect and nutritionally as CH4 represents a loss of feed energy. Karoline is a whole dairy cow mechanistic, dynamic model predicting nutrient supply and milk production. The objectives of this study were to revise the digestion and CH4 emissions modules of the Karoline model. In addition, a sensitivity analysis was conducted to evaluate the importance of the accuracy of input data required in predicting CH4 emissions. Modifications were made in the equations predicting digesta passage kinetics, microbial cell synthesis, digestion in the hind-gut, and utilization of hydrogen. The Karoline model predicted similar decreases in both organic digestibility (OMD) and neutral detergent fibre digestibility (NDFD) and improvements in the efficiency of microbial nitrogen synthesis with increasing dry matter intake (DMI) as reported in the literature. The proportion of ruminal digestion of total NDFD (0.95) and fecal metabolic and endogenous output (98g/kg DMI) also agree with the literature data. Predicted total CH4 emissions increased with a diminishing rate by increased DMI. Predicted CH4 emissions as a proportion of GE intake decreased linearly with increased DMI. The relationships between feeding level and CH4 emissions (a decrease of 7.8kJ/MJ gross energy per multiple of maintenance) were in good agreement with experimental data. The sensitivity analysis suggested that feed variables related to digestion kinetics of NDF [indigestible NDF (iNDF) and digestion rate of potentially digestible NDF] have a strong influence on predicted CH4 emissions; for example, predicted CH4 emissions decreased with increasing iNDF concentration. Digestion rates of starch and insoluble protein had smaller effects on predicted CH4 emissions than NDF digestion rates. Fat had a strong negative influence on predicted CH4 emissions (0.27kJ/MJ gross energy per 1g fat/kg DM). The sensitivity analysis suggested that accurate values of digestion kinetic variables are required for satisfactory predictions of CH4 emissions with mechanistic models. Based on reliable predictions of digestibility, microbial protein synthesis and CH4 emissions, it can be concluded that the revised Karoline model is a promising tool for predicting CH4 emissions and understanding the underlying mechanisms.


      PubDate: 2015-06-25T13:02:53Z
       
  • Effects of dietary oregano essential oil supplementation on the stress
           response, antioxidative capacity, and HSPs mRNA expression of transported
           pigs
    • Abstract: Publication date: Available online 5 June 2015
      Source:Livestock Science
      Author(s): T. Zhang , Y.F. Zhou , Y. Zou , X.M. Hu , L.F. Zheng , H.K. Wei , I. Giannenas , L.Z. Jin , J. Peng , S.W. Jiang
      Transportation stress affects carcass quality, metabolism and immune function. The utilization of feed additives is a possible strategy of mitigating physical and psychological stresses after animal transportation. Oregano essential oil (OEO) is an aromatic plant extract that mainly contains carvacrol and thymol. However, the effects of dietary supplementation with OEO for the welfare of transported pigs are limited. This study aimed to investigate the effect of OEO on alleviating stress and increasing antioxidative capacity after the transportation of finishing pigs. 180 crossbred pigs were randomly allocated to 1 of 3 diets: the basal diets, 200mgkg−1 vitamin E (VE), or 25mgkg−1 OEO. Each group was divided into two subgroups: no stress (NS) or transportation stress (TS) after 28d. Here we report that serum cortisol and norepinephrine concentrations of transported pigs were significantly reduced (P<0.05) in OEO diet. Reactive oxygen species (ROS) and malondialdehvde (MDA) were significantly increased in the serum (P<0.05) and liver (P<0.05) of TS pigs. Serum glutathione peroxidase (GSH-Px) was markedly raised (P=0.01) in dietary treatment. Liver SOD was dramatically raised no matter transportation (P<0.01) or dietary treatment (P=0.01). Liver heat shock protein (HSP) 27 and HSP90 were significantly increased (P<0.01) after transportation. These results indicated that OEO is beneficial in alleviating transportation stress and improving antioxidative activity, similar VE.


      PubDate: 2015-06-25T13:02:53Z
       
  • Measurements of body composition during late gestation and lactation in
           first and second parity sows and its relationship to piglet production and
           post-weaning reproductive performance
    • Abstract: Publication date: Available online 4 June 2015
      Source:Livestock Science
      Author(s): L.A. Rempel , J.L. Vallet , C.A. Lents , D.J. Nonneman
      The objective of this study was to characterize multiple body condition traits in a white crossbred composite population of first- and second-parity sows and, determine if these traits relate to litter production and reproductive parameters. Differences between parity or time were determined using a mixed model and reported as LSM±SE. As expected, parity 2 dams were heavier (P<0.0001; 202.5±1.57kg versus 174.1±1.35kg) than parity 1 dams. Of interest however, parity 2 dams lost more (P=0.0340) loin eye area from late gestation to weaning (−4.1±0.78cm2 versus −2.5±0.60cm2) but had a greater (P=0.0026) recovery in loin eye area from weaning to post-weaning (2.8±0.76cm2 versus 0.6±0.59cm2) versus primiparous females. However the period between weaning measurements and post-weaning measurements tended (P=0.0978) to favor parity 1 dams (16.0±0.35d) versus parity 2 dams (15.4±0.43d). Parity 2 dams also had a greater (P≤0.05) ovulation rate following weaning than parity 1 dams. Regression analyses indicated body weight of dams at several time points had a positive (P≤0.05) relationship to ovulation rate (range 0.03±0.012 to 0.05±0.013corpora luteakg−1). Piglet ADG was positively (P≤0.05) associated with dam body weight (range 0.30±0.103gkg−1 to 0.49±0.106gkg−1) and dam backfat thickness (range 0.93±0.363gmm−1 to 1.14±0.378gmm−1) regardless of parity. Regression analyses indicated interactions (P≤0.05) between parity and backfat thickness at weaning (−0.11±0.023pigletsmm−1) and post-weaning backfat thickness (−0.12±0.025pigletsmm−1) were negatively associated with number of nursed piglets weaned among parity 1 dams. Furthermore, loin eye area at weaning (−0.06±0.024pigletscm2 −1) and loss of loin eye area from late gestation to weaning (−0.05±0.020pigletscm2 −1) were negatively (P≤0.05) associated with number of nursed piglets weaned but were not influenced by parity in regression analyses. In conclusion, these data provide knowledge on differences in body composition before and after the lactation period in young dams under similar conditions. Of interest, second parity dams appear to have greater lean tissue elasticity versus primiparous females. Future studies will further refine the relationship among body composition in primiparous females and subsequent impact on sow longevity.


      PubDate: 2015-06-25T13:02:53Z
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2015