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  Subjects -> AGRICULTURE (Total: 668 journals)
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Journal Cover Livestock Science
   Journal TOC RSS feeds Export to Zotero [6 followers]  Follow    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 1871-1413
     Published by Elsevier Homepage  [2563 journals]   [SJR: 0.728]   [H-I: 63]
  • Single nucleotide polymorphisms in genes linked to ion transport and
           regulation of appetite and their associations with weight gain, feed
           efficiency and intake of Nellore cattle
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): M.H.A. Santana , R.C. Gomes , G.M. Ozawa , H. Fukumasu , S.L. Silva , P.R. Leme , P. Rossi Junior , P.R.L. Pires , P.A. Alexandre , P.S. Oliveira , F.V. Meirelles , J.B.S. Ferraz
      The aim of this study was to evaluate the effects of associations and allele substitution of DNA single nucleotide polymorphism (SNP) on genes linked to appetite control (NPY and PDE3B) and ion transport (ITPR1 and TRPM3) of average daily gain (ADG), feed conversion ratio (FCR), residual feed intake (RFI), residual BW gain (RWG), residual intake and body weight gain (RIG) and dry matter intake (DMI) of Nellore (Bos indicus) cattle. We evaluated the DMI, body weight and ADG of two hundred fifty-one animals kept in feedlots. The data were used to calculate the FCR, RFI, RWG and RIG. The associations of these variables with four SNPs (one in each gene cited above) were analyzes and the effects of allele substitution were estimated using PROC MIXED of SAS 9.3. The SNPs showed no association in genes ITPR1, TRPM3 and NPY, but we observed a significant association (P≤0.05) and effect of allele substitution in one SNP in gene PDE3B with DMI, RFI and RIG. The SNPs evaluated are polymorphic in Nellore cattle and the gene PDE3B should be further studied because it seems to have effect on feed intake and efficiency.


      PubDate: 2014-06-07T15:00:14Z
       
  • Genome-wide association study identifies three loci for intramuscular fat
           in Hanwoo (Korean cattle)
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): S.H. Lee , B.H. Choi , S.H. Cho , D. Lim , T.J. Choi , B.H. Park , J.H. Lee , C. Gondro , A. Sharma , C.G. Dang , S.S. Jang , H.K. Lee , H.S. Kang , B.S. Yang
      This study identified 59 SNPs significantly (P<0.001) associated with IMF using a genome-wide SNP panel, validating three SNPs using a validation dataset. The largest numbers (9 SNPs, 15% of the total significantly associated SNPs) of SNPs significantly associated with IMF were in BTA1. Of these, five were located between BTA1:22–27Mb and three were between BTA1:82–85Mb. The significantly associated SNPs accounted for only 3–5% of additive genetic variance. In the validation dataset, 3 SNPs (Hapmap54608-rs29020417, ARS-BFGL-NGS-5976 and Hapmap47624-BTA-44484) that showed an association with IMF in the single-point GWAS were significantly, positively associated with percent IMF (favorable alleles). One SNP (ARS-BFGL-NGS-29493) was significantly negatively associated (unfavorable allele). This study found that, in Hanwoo cattle, three loci were associated with IMF using GWAS and a validation dataset. The 3 SNPs explain 5.4% of phenotypic variation for IMF in Hanwoo commercial steers. In conclusion, IMF had a high heritability (0.5) but was expected to be affected by many loci with small effects.


      PubDate: 2014-06-07T15:00:14Z
       
  • Genomic information in pig breeding: Science meets industry needs
    • Abstract: Publication date: Available online 2 June 2014
      Source:Livestock Science
      Author(s): Noelia Ibañez-Escriche , Selma Forni , Jose Luis Noguera , Luis Varona
      The inclusion of genomic information on prediction of breeding values has been explored by the pig breeding industry as molecular techniques evolved.Except for a few successful cases, for example the HAL-1843®, the use of genomic information for pig breeding has been limited. The development of SNP chips with high density markers across the genome coupled with new statistical methods allowed genomic selection (GS) to become a common practice. GS application entailed important advantages for pig breeding as it increased the accuracy of the breeding values for selection candidates and offered an opportunity for the practice of new selection strategies. Nevertheless, the application of GS is not straightforward for every target trait and breeding scheme. Many efforts have been done to evaluate the new methods and strategies to efficiently implement GS in pig breeding. Several aspects of the population and breeding objectives must be considered before GS is applied. This paper reviews the current status and challenges faced by pig breeders in the implementation of GS and the future opportunities that may arise as molecular technologies advance.


      PubDate: 2014-06-07T15:00:14Z
       
  • Immunological effects of feeding macroalgae and various vitamin E
           supplements in Norwegian white sheep-ewes and their offspring
    • Abstract: Publication date: Available online 2 June 2014
      Source:Livestock Science
      Author(s): M. Novoa-Garrido , L. Aanensen , V. Lind , H.J.S. Larsen , S.K. Jensen , E. Govasmark , H. Steinshamn
      It is assumed that ewes raised in areas with long indoor winter feeding periods need to be supplemented with vitamins or other substances that help to maintain the health status of the animals. Various supplements are available on the market, but the most widely used supplemental antioxidant and vitamin E source is synthetic all-rac-α-tocopheryl acteate. The objective of the present study was to compare potential vitamin E and immune stimulant sources with synthetic vitamin E regarding bioactivity associated with immunological parameters in order to identify alternatives to synthetic vitamin E for small ruminants. Sources tested were meal of the seaweed Ascophylum nodosum and natural RRR-α- tocopheryl acetate. Forty pregnant ewes were randomly allocated to four treatment group with two replicates (5 ewes in each replicate). The treatments were supplements containing seaweed (SW: 546g Ascophylum nodosum/kg), natural vitamin E (NatE: 562.5mg RRR-α-tocopheryl acetate/kg), synthetic vitamin E (SyntE: 1125mg all-rac-α-tocopheryl acetate/kg), or no extra seaweed or vitamin E (control). The supplements were fed at an isoenergetic daily rate, on average 144g DM/ewe for SW and 114g DM/ewe for the three other treatments, from mating until start grazing season (200 days). It was assumed that 0.5mg RRR- α-tocopheryl acetate was equal to 1IU=1mg all-rac-α-tocopheryl acetate. The planned supplementation in the SyntE and NatE treatments were 140IU vitamin E/ewe daily, and the daily supplemental rate was on average for the whole experimental period 20, 146, 121 and 4IU in SW, SyntE, NatE and C treatments, respectively. The ewes and their newborn lambs were monitored throughout the entire indoor feeding period. Supplementing pregnant ewes with natural vitamin E had a positive effect on immunity against Mycobacterium sp. in the lambs, whereas supplementing ewes with seaweed interfered with the passive immunity of the offspring resulting in a mortality rate of 35%, compared with 10% in C, 5.6% in NatE and 0% in SyntE. The adaptive immunity of the lambs was not affected by seaweed supplementation. In the ewes, it seemed that supplementation with either seaweed, natural vitamin E or synthetic vitamin E had no beneficial health effects, and serum IgG concentrations were reduced in the seaweed treatment group.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effect of floor type on behavior and productive performance of growing
           rabbits
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): Zs. Gerencsér , K. Szendrő , Zs. Szendrő , M. Odermatt , I. Radnai , I. Nagy , A. Dal Bosco , Zs. Matics
      In this study the results of two experiments are presented. The aims of the study were to examine the location preference of growing rabbits depending on the floor types (plastic-mesh, wire-mesh and deep-litter) and temperature (low, medium and high; Trial 1), and to evaluate the productive performance of growing rabbits at medium room temperature (Trial 2). In Trial 1 at the age of 5 weeks, the rabbits were randomly placed in one of the three pens each with a basic area of 3.8m2 (43 rabbits/pen, 11.3rabbits/m2). The floor of each pen was 1/3 wire-mesh, 1/3 plastic-mesh and 1/3 deep-litter. The treatment was repeated in winter, spring and summer with the following room temperatures: 10–11°C (low, n=129), 17–20°C (medium, n=129) and 22–26°C (high, n=129), respectively. With infrared cameras, 24h video recordings were made once a week, between 5 and 11 weeks of age. The number of rabbits in each location in the pens was recorded at every 30min. The rabbits showed the lowest preference for deep-litter (P<0.001) at each age, regardless of the temperature. The preference for wire-mesh or plastic-mesh floor depended on the temperature. At lower temperature most rabbits preferred staying on plastic-mesh, however at medium and higher temperature more rabbits chose the wire-mesh floor during the final period of fattening. In Trial 2 the productive performance was examined. At the age of 35 days, the rabbits (n=126) were randomly sorted to three groups and were housed in pens with a basic area of 1.27m2 (14 rabbits/pen, 11rabbits/m2). The floor type of the pens was plastic-mesh, wire-mesh or deep-litter. The body weights of rabbits between the ages of 7 and 10 weeks were significantly higher in the group on wire-mesh and plastic-mesh compared to the rabbits on deep-litter. Twelve week-old rabbits showed no significant differences among the groups. No significant differences were found for feed intake, feed conversion ratio or mortality between the ages of 5 and 12 weeks, however significant differences were recorded between the plastic-mesh and deep-litter groups for the average daily weight gain. It could be concluded that rabbits do not prefer staying on deep-litter, their preferences between wire-net and plastic-mesh floor depends on the temperature and age. Housing the growing rabbits on wire- or plastic-mesh floors had no substantial differences, while housing rabbits on deep-litter negatively affected certain traits, but the alterations were smaller compared to the results of the relevant literature.


      PubDate: 2014-06-07T15:00:14Z
       
  • Characterization of dairy cattle germplasm used in Mexico with national
           genetic evaluations in importing and exporting countries
    • Abstract: Publication date: Available online 5 June 2014
      Source:Livestock Science
      Author(s): Rodolfo Ramírez-Valverde , Rafael Núñez-Domínguez , Ana L. Palacios-Jiménez , Juan S. Jiménez-Carrasco
      The objective of this study was to characterize and compare predicted transmitted abilities of Brown Swiss and Jersey cattle used in Mexico (MX), and those obtained in the United States (US) and Canada (CA). The database used in this study came from imported American and Canadian Brown Swiss and Jersey germplasm to MX. Currently, these animals are registered in MX and have national genetic evaluations in importing and exporting countries. Means and trends over time of predicted transmitted abilities (PTA) and their reliabilities were computed and compared for the origins of animal groups. Adjusted genetic correlations (r g ) between PTAs in paired countries were estimated. The results indicate that importation of germplasm has occurred mainly during the 1990s, and some animals from the exporting countries should not be used in the importing country, if the main selection objective is milk yield. Most Mexican breeders are importing genetic resources below genetic base means (negative PTA values), not only in their countries of origin but also in the importing country, and this suggests that they might not be acquiring genetic material based on the PTA of milk yield or any other genetically evaluated trait. The r g of animals with evaluations in MX and the US ranged between 0.40 and 0.70; however, for Jersey animals evaluated in MX and CA the r g was slightly higher than 0.8, suggesting fewer germplasm problems of genotype-by-country interaction and therefore, a lower risk to use those animals in the importing country. Using only the importation of germplasm as a strategy to achieve sustainable genetic progress in the importing country is probably not a good alternative, and there is a need for a local selection program of their dairy cattle populations.


      PubDate: 2014-06-07T15:00:14Z
       
  • Genetic parameters and calving ability index for direct and maternal
           calving difficulty and stillbirth in Iranian Holstein cows
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): Heydar Ghiasi , Majid Khaldari , Reza Taherkhani
      A total of 72,124 calving difficulty and stillbirth records of Iranian Holstein cows in 15 herds that were collected, from 1981 to 2005, and used to estimate genetic parameters and also constructing a calving ability index. A maternal effect model was used for genetic parameter estimation. In order to construct calving ability index, direct and maternal calving difficulty and stillbirth were included in aggregate genotype. Estimated heritability for maternal calving difficulty and direct calving difficulty and stillbirth were 0.012, 0.041 and 0.066, respectively. Genetic correlation of stillbirth with maternal and direct calving difficulty was 0.22 and 0.10, respectively. The genetic correlation between direct and maternal calving difficulty was −0.43. Expected genetic gains for direct and maternal calving difficulty and stillbirth using first calving ability index, that included all traits in aggregate genotype were −0.335,−0.028 and −0.0054, in liability scale and −7,−0.5 and −0.4 percent in observed scale, respectively. Expected genetic gains for direct and maternal calving difficulty and stillbirth in a second calving ability index that included only direct calving difficulty were −0.375,0.13 and −0.0027 in liability scale and −7.2,+4 and −0.3 percent in observed scale, respectively. Selection based on direct calving difficulty cannot reduce calving difficulty in population; therefore in order to reduce calving difficulty selection should be based on both direct and maternal calving difficulties.


      PubDate: 2014-06-07T15:00:14Z
       
  • Artificial insemination causes uterine hemodynamic alterations in suckled
           beef cows subjected to an ovulation synchronization program
    • Abstract: Publication date: Available online 5 June 2014
      Source:Livestock Science
      Author(s): Bruna Marcele Martins de Oliveira , Rubens Paes de Arruda , Helder Esteves Thomé , Milton Maturana Filho , Guilherme Cain de Oliveira , Carina de Fátima Guimarães , Luciano Andrade Silva , Marcílio Nichi , Eneiva Carla Carvalho Celeghini
      The objective of the present study was to verify the uterine hemodynamic of suckled beef cows after a timed artificial insemination (TAI) by Doppler ultrasound. Eighteen cows were randomly assigned in one of two groups: non AI (CG, n=9) and AI group (AIG, n=9). Ultrasound evaluations were performed in five spectral mode moments (30 hours before AI, 4, 24, 48, and 168 hours after AI) to evaluate the resistance index (RI) of the uterine artery and in four Doppler color mode moments (4, 24, 48 and 168 hours after AI) to evaluate the percentage of the uterine horns vascularization. The animals showed similar vascularization in the beginning of the experiment. The data were first evaluated according to the side where ovulation occurred and no effects were observed. Vascularization was assessed in each group at each time. No differences were observed in any of the time points. Time effect was observed in both groups and behavior was similar for the groups. Highest values of RI were observed 48 hours after AI, followed by the 168 hours and values obtained 24 hours after AI. The lowest values of RI were noted 4 hours after AI, followed by the observation 30 hours before AI. Regarding the effect of time to EV, time effect was not observed in either group. Since there was no interaction group⁎time, data were analyzed for each group, regardless of the time and for each time, regardless of the group. The RI values were lower for AIG when compared to the CG; however, no differences were observed between the groups as far as uterine vascularization scores. Four hours after AI, the RI values were lower when compared to 24, 48 and 168 hours following AI, showing no difference in relation to 30 hours before AI. Thirty hours before AI, the RI values were lower when compared to 48 and 168 hours after AI, no different than the values observed 24 hours after AI. The highest RI value appeared 48 hours after AI, where this value was not statistically different from the one found 168 hours after AI. On the other hand, there was no difference between the vascularization scores regarding the evaluation periods (P>0.05). Artificial insemination of female bovines reduce uterine artery RI, but do not change the uterine vascular score. Moreover, changes in the uterine hemodynamics in cows are related to the period of evaluation.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effects of inclusion of waste vinegar residue in the diet of laying hens
           on chyme characteristics and gut microflora
    • Abstract: Publication date: Available online 6 June 2014
      Source:Livestock Science
      Author(s): Z.T. Song , X.F. Dong , J.M. Tong , Z.H. Wang
      The objective of this study was to evaluate the effects of inclusion of waste vinegar residue (WVR) in the diet of laying hens on chyme characteristics and gut microflora. A total of 96 60-wk-old Hy-Line Brown laying hens were selected and fed three diets including a corn and soybean meal-based control diet and two other diets with 20g/kg and 40g/kg of WVR. After 27d feeding period, digesta was collected for protease activity, pH value and microflora determination. Bacterial genetic diversity was determined using DGGE analysis of the V3 region of 16S rDNA PCR products (230bp) obtained from primers specific for the domain Bacteria. Inclusion of 20g/kg and 40g/kg of WVR in the diet decreased the digesta pH value in the gizzard (P=0.003) and increased pepsin activities in the gizzard of laying hens (P=0.032). Species of Enterobacter and Peptostreptococcaceae were more predominant in the cecum and ileum of laying hens, respectively. It is concluded that inclusion of 40g/kg of WVR in the laying hen diet modifies intestinal pH value and pepsin activities in upper gastrointestinal tract and affects lower gut microflora in laying hens.


      PubDate: 2014-06-07T15:00:14Z
       
  • A fast method for evaluating opposing homozygosity in large SNP data sets
    • Abstract: Publication date: Available online 6 June 2014
      Source:Livestock Science
      Author(s): Mohammad H. Ferdosi , Vinzent Boerner
      Optimized algorithms are indispensable for analyzing large SNP data sets. To date, research has focused on the development of methods for calculating genomic relationship matrices. However, little attention has been given to algorithms for calculating the number of opposing homozygous SNP loci(OH) between genotyped individuals, where this parameter can be used to detect pedigree errors, genotyping errors, mixing of DNA samples, or for paternity tests. A recently proposed approach(LOOP) is sufficient for small data sets but not applicable to larger data sets in terms of number of SNPs and genotyped individuals. In this paper we propose a fast method for the calculation of OH in matrix format(OHM). This method is very fast and easy to implement. For example, it can create the OHM for 12,000 individuals genotyped for 40,000 SNPs with only 12% of the real time used by the LOOP approach. Thus, calculation of OHM from a sequence of matrix manipulations substantially increased the speed for determining the number of opposing homozygous SNP loci between all genotyped individuals of a data set. Given the availability of packages facilitating parallel processing this holds even when using R, and therefore allows inference from OHM even for large data sets.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effects of dietary supplementation with benzoic acid on intestinal
           morphological structure and microflor in weaned piglets
    • Abstract: Publication date: Available online 6 June 2014
      Source:Livestock Science
      Author(s): H. Diao , P. Zheng , B. Yu , J He , X.B. Mao , J. Yu , D.W. Chen
      A total of 72 weaned pigs [(Yorkshire × Landrace) × Duroc] with an average BW of 6.03±0.78kg (24d of age) were used in a 42-d trial to explore the potential mechanisms of dietary benzoic acid on gut health in weaned pigs. Pigs were randomly allotted to two groups with six replications per group and fed with a basal diet (control) or basal diet supplemented with 5000mg/kg benzoic acid (benzoic acid).The results showed that benzoic acid supplementation decreased the pH values of the digesta in the colon on 14th day and in the ileum and cecum on 42nd day of pigs (P<0.05). The number of Bifidobacterium in ileum and Bacillus in cecum of pigs fed benzoic acid diet were greater than pigs fed the control diet on 14th day (P<0.05), the number of Escherichia coli in ileum and cecum on 42nd day were decreased in pigs fed benzoic acid diet (P<0.05), the number of Enterococci in ileum were decreased on 14th and 42nd day in pigs fed benzoic acid diet (P<0.05). When compared with control, benzoic acid increased the content of propionic acid and total VFA in cecum on 14th day (P<0.05), decreased the concentrations of NH3-N in cecum on 14th day and 42nd day (P<0.05). The villous height in duodenum and ileum on 14th day were greater in pigs fed benzoic acid diet(P<0.05), benzoic acid increased villous height in ileum on 42nd day (P<0.05), decreased crypt depth in duodenum on 14th day (P<0.05), and increased the villous height:crypt depth ratio in duodenum, jejunum and ileum on 14th day and 42nd day (P<0.05). In conclusion, diet supplemented with 5000mg/kg benzoic acid can improve the gut health of piglets through decreasing the digesta pH values, maintaining the balance of microflora and promoting the development of intestinal morphology in weaned pigs.


      PubDate: 2014-06-07T15:00:14Z
       
  • Vascular endothelial growth factor expression correlated with microvessel
           density in the antral follicle of sheep ovary
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): Linlin Hao , Dian Wang , Guishan Zhang , Wei Ma , Changhong Li , Huaizhi Jiang
      Vascular Endothelial Growth Factor (VEGF) promotes the proliferation and angiogenesis of endothelial cells and plays important physiological roles in the follicular development and oocyte maturation. However, the role of VEGF in endothelial cells is only partly understood in the angiogenesis of the sheep ovary. Our study analyzed the protein expression of VEGF and its correlation with microvessel density (MVD) in the sheep ovary from 0 to 15d after the synchronization of estrus. The results showed that VEGF was expressed at increasingly higher levels from the primordial follicle to the secondary follicle (P<0.05). In Graafian follicles VEGF expression was increased from 0 to 5d followed by a significant decline (P<0.05), and it was markedly increased again at 15d (P<0.05). Capillaries began to appear around the follicular theca of the primary follicle. MVD significantly increased around the secondary follicle and in Graafian follicles from 0 to 5d and 12 to 15d (P<0.05). Pearson correlation analysis showed a highly positive correlation between VEGF expression level and MVD in the primordial follicle, primary follicle and secondary follicle (r=0.81, p=0.01). These data indicate that VEGF has a close relationship with vascular regeneration of sheep ovary.


      PubDate: 2014-06-07T15:00:14Z
       
  • Plasma metabolites associated with residual feed intake and other
           productivity performance traits in beef cattle
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): B.K. Karisa , J. Thomson , Z. Wang , C. Li , Y.R. Montanholi , S.P. Miller , S.S. Moore , G.S. Plastow
      The objective of this study was to identify blood metabolites associated with variation primarily in residual feed intake (RFI) in two populations of beef steers at the University of Guelph and University of Alberta, Canada, representing the discovery and validation populations, respectively. Other productivity performance traits including average body weight (ABW), average feed intake (AFI), dry matter intake (DMI) and average daily gain (ADG) were also investigated. In the discovery population, blood plasma samples were obtained from 32 steers (16 high- and 16 low-RFI, from a population of 112 steers and maximizing the divergence between groups for RFI) at three periods 1, 2 and 3, corresponding to weeks 2, 6 and 10 respectively of the 140d feeding and performance test. In the validation population, blood samples were obtained from 20 (10 high and 10 low RFI) steers from periods 1 and 2 corresponding to weeks 2 and 6 of a 90d feeding test period. Metabolite concentrations in plasma were determined using nuclear magnetic resonance (NMR) and multiple regression analysis was performed in SAS 9.1. Creatine and glycine were associated (P<0.05) with RFI in period 1 accounting for 36.3% of the phenotypic variation in RFI. At period 2, threonine, carnitine, acetate, creatine, phenylalanine, lysine, citrate, betaine, glutamate and hippurate were significant (P<0.05) and accounted for 74.2% of the variation in RFI. At period 3, hydroxyisobutyrate, tyrosine and formate were significant (P<0.05) and accounted for 52.1% of the variation in RFI. In the validation population, three metabolites (creatine, carnitine and hippurate) were significant (P<0.05) in both discovery and validation populations and these three metabolites accounted for 32% of the phenotypic variation in RFI in the validation population. Some of the metabolites associated with RFI were also associated with other performance traits discussed in subsequent sections. Metabolic networks for RFI in each period were reconstructed using IPA and suggested that the biological processes associated with RFI were involved in energy and protein metabolism as well as metabolism of urea and methane. The analysis of metabolites and evaluation of biological processes create a better understanding of the metabolic processes that affect RFI. Upon further validation, these indicators may have potential to be utilized as biomarkers to enhance the selection of beef cattle.


      PubDate: 2014-06-07T15:00:14Z
       
  • Performance of purebred Welsh Mountain and crossbred ewes in a hill
           environment
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): B.T. Wolf , B.M.L. McLean , O.D. Davies , J.B. Griffiths
      The aim of this study was to compare the body weights, body condition scores, survival and litter weights of lamb produced by pure Welsh Mountain ewes with those of crossbred Cheviot, Lleyn, Poll Dorset and Texel ewes in a hill environment. Ewes were mated to Suffolk rams and recorded over the first 3 seasons of production. Between lambing and weaning, ewes rearing single lambs grazed semi-natural hill swards (1.5ewes/ha) and those rearing twins grazed improved enclosures (10ewes/ha). Crossbreeding significantly (P<0.001) increased body weights at all ages, with values for four-year old ewes of 45.9, 57.2, 51.6, 57.8 and 58.5kg in purebred Welsh Mountain and Cheviot, Lleyn, Poll Dorset and Texel crossbred ewes respectively. Individual lamb growth rates from birth to 8 weeks and from 8 weeks to weaning were significantly higher in the progeny of crossbred ewes (P<0.001) with highest growth rates for lambs reared by Poll Dorset and Texel cross ewes. Individual lamb weaning weights were 27.0, 29.4, 29.2, 30.4 and 30.7kg for lambs reared by purebred Welsh Mountain and Cheviot, Lleyn, Poll Dorset and Texel crossbred ewes respectively. Survival rates to third mating were 0.73, 0.77, 0.83, 0.72 and 0.75 (P<0.05), litter size reared was 1.22, 1.33, 1.49, 1.43 and 1.25 (P<0.001) and litter weights at weaning were 37.1, 43.5, 46.1, 46.5 and 44.2 (P<0.001) for purebred Welsh Mountain and Cheviot, Lleyn, Poll Dorset and Texel crossbred ewes respectively. Efficiency expressed as kg litter weight/kg ewe pre-tupping weight0.75 was significantly improved (P<0.001) by crossbreeding. Total litter weight at weaning over three lamb crops per ewe entering the flock was increased from 78.4kg in purebred Welsh Mountain ewes to between 97.1kg in Cheviot and 109.7kg in Lleyn crossbred ewes. It is concluded that where feed resources are adequate, the retention of crossbred ewes in the hill flock can give significant improvements in productivity.


      PubDate: 2014-06-07T15:00:14Z
       
  • Modelling cattle population as lifetime trajectories driven by management
           options: A way to better integrate beef and milk production in emissions
           assessment
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): L. Puillet , J. Agabriel , J.L. Peyraud , P. Faverdin
      Methods to assess the consequences of mitigation scenarios on greenhouse gas (GHG) emissions in the cattle sector have been widely developed. A crucial issue of these methods is handling the co-products in emissions allocation. In the cattle sector, milk and beef production systems are closely interconnected because of the meat obtained from dairy culled cows and fattened surplus calves. To fully evaluate a change in the dairy sector, the change in the meat production induced should also be taken into account. With this objective, a national cattle population model was developed, based on three sub-models. The herd functioning sub-model represents the bunch of cattle trajectories generated by reproductive and finishing processes depending on breeds, production levels and finishing types. Assuming a steady state herd, the demographics sub-model represents the number of animals in age groups depending on trajectories length. The production sub-model represents the number of animals slaughtered or exported, the quantity of carcasses, milk and direct GHG emissions. The model was calibrated on French data. The simulation of a reference scenario reflecting the French situation in 2010 confirmed that the model allowed linking cattle trajectories, demographics and production of milk, meat and direct GHG emissions. Scenarios for the dairy sector were simulated to illustrate the potential of such modelling approach to evaluate direct GHG emission at the national level. The results confirmed that the interconnection between dairy and beef sectors can modify the benefit of strategies such as dairy intensification. Further, the results also demonstrated that the compensation between beef and dairy cattle to achieve production objectives lead to a change in the type of carcass produced due to differences between breeds and finishing strategies. Accounting for such differences allows deepening the evaluation of the consequences of GHG mitigation options.


      PubDate: 2014-06-07T15:00:14Z
       
  • Walking kinematics of growing pigs associated with differences in
           musculoskeletal conformation, subjective gait score and osteochondrosis
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): S. Stavrakakis , J.H. Guy , O.M.E. Warlow , G.R. Johnson , S.A. Edwards
      Despite orthopaedic problems being a major concern for the pig industry, there is a lack of biomechanical, hence quantitative, investigation of locomotor pathology in pigs. The objective of this study was to determine whether there are detectable changes in joint and stride kinematics of clinically sound and unsound pigs, with or without post mortem joint lesions of osteochondrosis. A cohort of 24 pigs underwent five camera-based motion captures, 7–10d apart and between 63kg and 90kg average liveweight, during which 3D coordinate data of reflective skin markers attached to leg anatomical landmarks were collected. Pigs walked on the same solid concrete walkway during captures. Statistical analysis was performed within captures across pigs which were categorised based on a series of deficiency characteristics. Results showed that pigs with clinical deficiencies and degenerative joint lesions had altered kinematics, although there were capture-related fluctuations in the findings. For pigs with conformational and perceived gait abnormalities there were significant differences in joint flexion values and left and right flexion symmetry, mainly reflected in the swing ranges of motion, compared to sound animals. Buck-kneed front legs were found to cause flexion deficiencies during the stance phase of stride cycles (P≤0.05; −9 degrees). Pigs with osteochondral joint lesions had mainly stance-related angular changes (P≤0.05) and asymmetry. Irregularity in the step-to-stride length relationship was elevated in both clinically and subclinically deficient pigs (respectively P=0.06, 1.5 times greater; P≤0.05; 1.5 times greater), but not the healthy pigs. These data provide basic kinematic values for clinically sound and affected pigs which could be used for further research into early and automated detection of leg disorders as well as for improved selection of breeding animals for longevity characteristics.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effect of concentrate supplementation on herbage intake and live weight
           gain of sheep grazing a semi-arid grassland steppe of North-Eastern Asia
           in response to different grazing management systems and intensities
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): B.M. Bösing , A. Susenbeth , J. Hao , S. Ahnert , M. Ohm , U. Dickhoefer
      An increasing human population and growing demand for food of animal origin intensified livestock production and lead to overgrazing and desertification in semi-arid grasslands. Strategies for sustainable livestock production that protect steppe vegetation and satisfy farmers׳ economic interests are strongly needed. This study analysed the effects of a moderate concentrate supplementation on organic matter digestibility (dOM), organic matter intake (OMI), metabolisable energy intake (MEI), and live weight (LW) gain of sheep grazing at different intensities to evaluate its potential contribution to profitable livestock production at conservative stocking densities (SD). In 2010, a grazing experiment was conducted in the Xilin River Basin, the Inner Mongolian steppe, China (E116°42′ N43°38′) using 337 female Mongolian fat-tailed sheep (30.2±4.3kg LW). The effect of concentrate supplementation was tested in two different grazing management systems and six classes of herbage allowances (HA). While experimental plots had only been used for grazing in previous years in the continuous system, grazing and hay-making had been alternated annually on plots of the alternating system. The SD ranged from light to heavily grazed with 2.1–10.3 sheep/ha and were adjusted every month to maintain similar HA across the grazing season. Four sheep per plot received 250g/d of a corn–wheat-based concentrate feed (SUP), while four non-supplemented (NSUP) sheep were used as control. Faecal samples were collected on five days each in July, August, and September. The dOM was estimated from faecal crude protein concentration and faeces excretion quantified using the marker titanium dioxide. The animals were weighed monthly to determine daily LW gain. The dOM was higher in SUP than NSUP sheep (0.557 vs. 0.533, RSD: 0.016). As a consequence, daily OMI and LW gain of SUP sheep (74g/kg0.75 LW; 121g) were higher than of NSUP sheep (68g/kg0.75 LW, RSD: 6.4; 86g, RSD: 24.6) despite a decrease in herbage OMI of 0.41g per 1g concentrate feed. Grazing system had no influence on dOM, OMI, or LW gain of sheep. The effects of supplementation were independent of HA class, and OMI, herbage OMI, MEI, and LW gain were higher in the beginning than in the end of the experiment. Moderate concentrate supplementation to grazing sheep strongly increases LW gain of individual animals and might offer a valuable contribution to increase individual productivity, maintaining the output per area at lower SD. A reduced herbage OMI alleviates grazing pressure and can thus maintain long-term grassland productivity.


      PubDate: 2014-06-07T15:00:14Z
       
  • “Photozoometer”: A new photogrammetric system for obtaining
           morphometric measurements of elusive animals
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): V. Gaudioso , E. Sanz-Ablanedo , J.M. Lomillos , M.E. Alonso , L. Javares-Morillo , P. Rodríguez
      This work presents and evaluates a new methodology for the measurement of animal morphometrics. With this method, measurements are obtained using 3D image analysis, or photogrammetry, from pairs of pictures taken with a portable instrument incorporating two synchronized cameras. The method facilitates measurements of animals in their natural environment without the need to immobilize or anesthetize the animals or to place any external measuring device in the environment. The proposed methodology is useful if traditional measurements of large animals are not possible or difficult, costly or dangerous, as is the case with wild animals such as elephants, rhinoceroses, hippopotamuses or dangerous or elusive species, such as fighting bulls and ostriches, which would be difficult to measure manually. To evaluate the methodology, zoometric measurements on cows were performed using both the proposed method and traditional methods. In general, the precision obtained by the proposed methodology was greater than or equal to that obtained with conventional instruments. There were no biases or systematic deviations greater than 1cm and the photogrammetric measurements generally showed an accuracy within 0.5cm.


      PubDate: 2014-06-07T15:00:14Z
       
  • Pen hygiene, N, P and K budgets and calculated nitrogen emission for
           organic growing–finishing pigs in two different housing systems with
           and without pasture access
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): Anne-Charlotte Olsson , Knut-Håkan Jeppsson , Jos Botermans , Hans von Wachenfelt , Mats Andersson , Christer Bergsten , Jørgen Svendsen
      The effects of two housing systems (deep litter and straw-flow), with and without access to pasture during the summer period, were studied in an organic growing–finishing pig herd. Pen hygiene studies, N, P and K budgets and estimations of nitrogen emission were made for two batches (8pens/batch and 16pigs/pen) one during the winter period and one during the summer period. It was concluded that there were no significant differences in overall pen hygiene between the housing systems. During the growing period in the summer, the pen hygiene on the outdoor concrete area was significantly better (P<0.05) when the pigs had access to pasture. In addition, the total pen hygiene (indoors+concrete area outdoors) tended (P=0.09) to be cleaner with access to pasture during the summer period. The N-losses of the amount of N excreted were the same (26–27%) during the winter period as during the summer period. The amount of N excreted was on average 6.0kg N per pig during the winter, and 4.2kg N per pig during the summer; this was equivalent to an N-emission of 1.5–1.6kg N/pig during winter and 1.1–1.2kg N/pig during summer. The difference was mainly due to a higher feed consumption and more straw usage during the winter. In comparison to the calculated N-emissions from a non-organic pig, this was approximately 3–4 times greater. In the present study, a 10% larger feed usage explained the differences in N-emission by a factor of 1.2, a 15% higher crude protein level explained the differences by a factor of 1.3 and finally a larger fouled area explained the differences by a factor of 2.3. Differences in temperature and airflow were not taken into account in these calculations.


      PubDate: 2014-06-07T15:00:14Z
       
  • Estimation of backfat thickness using extracted traits from an automatic
           3D optical system in lactating Holstein-Friesian cows
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): Astrid Weber , Jennifer Salau , Jan Henning Haas , Wolfgang Junge , Ulrike Bauer , Jan Harms , Olaf Suhr , Karsten Schönrock , Hubert Rothfuß , Sascha Bieletzki , Georg Thaller
      Increasing milk production per cow over the last decades has led to a more intense negative energy balance and extended the duration of body fat mobilization. Management of body condition requires that body condition scores be evaluated on a visual basis. A more objective approach is the measurement of the backfat thickness (BFT) using an ultrasound device. Metering precision of 1mm enables the recognition of even slight changes in the subcutaneous fat thickness. Because both methods are time consuming in large dairy herds, automating body condition׳s routine evaluation is of rising concern. This study investigated whether traits of the animals׳ rear area extracted from Time-of-Flight camera recordings might be useful indicators of BFT. Furthermore, characteristics of BFT within and across different lactation stages were analyzed. Data recording was performed on the dairy research farm Karkendamm of the Institute of Animal Breeding and Husbandry of the University of Kiel (Germany) from July 2011 to May 2012. BFT measures (n=2931) and two measures (n=1779 and n=1848) obtained from Time-of-Flight recordings from 96 primiparous and multiparous Holstein-Friesian dairy cows were analyzed using seven different linear (mixed) models. BFT estimation using the cow as random or fixed effect, lactation week and observation month as fixed effects, and a linear regression on the two Time-of-Flight measurements has been promising. The correlation among observed values and estimator was 0.96. Repeatability of BFT within each of the three lactation stages was large and ranged from 0.80 to 0.89. Correlations of cow effects among lactation stages were also high and range from 0.65 between first and third lactation stage to 0.89 between second and third lactation stage.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effects of detoxified Jatropha curcas kernel meal in finishing pig diets
           on their performance, carcass traits, meat quality and intoxication
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): B. Berenchtein , A.L. Abdalla , T. do Prado Paim , M. Sbardella , H. Louvandini , A.L.A. Filho , D. Dhanasekaran , P.P. dos Santos
      Jatropha meal, produced as co-product of biodiesel production process, can be used in animal diets as a feedstuff. Hence, the purpose of this study was to evaluate effects of increasing dietary levels (0%, 2%, 4%, 6%, and 8%) of detoxified Jatropha curcas kernel meal (DJCM) on performance, carcass traits, meat quality, and intoxication of bioactive molecules, such as the phorbol esters, by hepatic transaminase enzymes in finishing pigs. Sixty hybrid crossbred pigs (70.7±3.3kg body weight, BW) were assigned to 5 treatments with 6 replicate pens per treatment and 1 castrated male and 1 female per pen in a randomize complete block design. Isoenergetic and isoproteic diets and water were provided ad libitum to the pigs during 30-d growth study. At the end of the experimental period, pigs were slaughtered and hot carcass yield weight, carcass length, backfat thickness, loin eye area, and muscle-to-fat ratio were determined. In addition, blood samples were collected for the analysis of hepatic enzymes, and Longissimus dorsi muscle samples were also collected for the measurement of pH, color, and water drip loss. Increasing dietary levels of DJCM reduced (P<0.001) final BW, ADG, ADFI, and carcass length quadratically, and hot carcass weight and backfat thickness linearly (P<0.05). No effects were observed on meat quality with the dietary inclusion of DJCM. Increasing levels of dietary DJCM showed a negative quadratic effect (P<0.05) on aspartate aminotransferase hepatic enzyme without any effects on alanine aminotransferase. In conclusion, the DJCM decreased growth performance and carcass traits because of the presence of bioactive molecules. Further studies are needed to investigate the effect of bioactive molecules present in DJCM and the possibility of removing those bioactive compounds.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effect of dietary crude glycerin on growth performance, nutrient
           digestibility and hormone levels of Iberian crossbred pigs from 50 to
           100kg body weight
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): J. Orengo , C. Villodre , J. Madrid , S. Martínez , M.J. López , M.D. Megías , L. Valera , F. Hernández
      The aim of this study was to determine the effect of crude glycerin addition on the growth performance, nutrient digestibility and blood hormone levels of Iberian crossbred pigs kept under intensive conditions. The study was carried out with 80 crossbred pigs (Iberian gilts×Duroc boars) of both sexes over a 101-d period (54±3kg initial BW). Treatments were arranged in a 2×2 factorial design, the factors being dietary treatment (control or 10% glycerin) and gender (barrow or gilt). Crude glycerin was included as a replacement for wheat in diets formulated to provide equal net energy and digestible lysine levels. Glycerin-fed pigs had higher average daily gain and average daily feed intake than pigs fed the control diet (P<0.05). No differences were found in the gain to feed ratio. With regard to the gender, barrows consumed more feed, grew more and reached a higher final BW compared with gilts (P<0.05). Nutrient digestibility was not affected by the glycerin content or the gender. However, there was a tendency for acyl-ghrelin levels to be higher in glycerin-fed pigs (P=0.058). Also, gilts showed increased concentrations of acyl-ghrelin and lower insulin compared with barrows (P<0.05). In conclusion, 100g/kg of glycerin can partially replace wheat without affecting feed efficiency or nutrient digestibility in Iberian crossbred pigs. However, further research is needed to clarify the potential relationship between glycerin inclusion levels in the diet and the plasmatic levels of hormones related to feed intake and energy balance control.


      PubDate: 2014-06-07T15:00:14Z
       
  • Growth performance, blood cell profiles, and meat quality properties of
           broilers fed with Saposhnikovia divaricata, Lonicera japonica, and
           Chelidonium majus extracts
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): J.H. Park , S.N. Kang , G.M. Chu , S.K. Jin
      An experiment was conducted to evaluate the effect of 3 plant extracts, Saposhnikovia divaricata extract (SDE), Lonicera japonica extract (LJE), and Chelidonium majus extract (CME) on growth performance, blood cell profiles, and meat quality in broilers. Qualitative and quantitative analysis of the compounds of phenolic acids and flavonoids was performed by high performance liquid chromatography with diode-array detection for characterization of the selected extracts. Total amounts of phenolic acids and flavonoids in the extracts were in the order of LJE, CME, and SDE. These extracts were added at a rate of 0.2% to the starter and finisher basal diets of broilers, and a feeding study was conducted in battery cages for a period of 5 week. A total of 240, one-day-old male Arbor Acres broilers were allotted to 4 treatments with 4 replicate cages and 15 broilers per cage. The results indicated that daily weight gain was greater in the CME treatment groups and the plant extract treated groups (SDE+LJE+CME) than the control group (P=0.044, P=0.036, respectively), while feed intake was not different among the groups. The feed conversion of broilers fed the SDE-supplemented diets was lower than the control groups (P=0.044). White blood cells, neutrophils, lymphocytes, monocytes, and eosinophils in broilers fed the LJE, CME, and plant extract-supplemented diets (SDE+LJE+CME) were greater than those fed the control diets (P<0.05). In addition, red blood cells, hemoglobin, and hematocrit were also elevated in broilers fed the LJE diets. Volatile basic N and thiobarbituric acid reactive substance values of broiler breast meat was reduced by the addition of LJE or CME, respectively (P=0.036, P=0.023, respectively). No changes were observed in the meat color, pH, cooking loss, drip loss, fatty acid concentrations, and texture properties, except for the adhesiveness of broiler breast meat, which was increased by the addition of SDE, LJE, and plant extract-supplemented diets (SDE+LJE+CME) compared with the control (P<0.001). These results indicate that supplementation of these plant extracts in the broiler diet may potentially improve weight gain, blood cell profiles, and meat qualities.


      PubDate: 2014-06-07T15:00:14Z
       
  • Influence of feed form on growth performance, ileal nutrient
           digestibility, and energy utilisation in broiler starters fed a
           sorghum-based diet
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): M.R. Abdollahi , V. Ravindran , B. Svihus
      A broiler starter (1–21d) diet based on a finely ground red sorghum was used to develop 3 feed forms: (1) unprocessed mash, (2) pellets steam-conditioned at 70°C, and (3) re-ground pellets following steam-conditioning at 70°C. The influence of dietary treatments on the growth performance, coefficient of apparent ileal digestibility (CAID) of N, starch, fat, Ca, and P, and apparent metabolisable energy (AME) in broiler starters was evaluated. A total of 144 one-day-old male broilers (Ross 308) were individually weighed and allocated to 18 cages (8 broilers/cage), and cages were randomly assigned to 3 dietary treatments. Broilers fed the pelleted diet gained more (P<0.05) weight and had a greater (P<0.05) feed intake (FI) than those fed mash and re-ground pellet diets. Re-grinding the pellets resulted in similar weight gain and FI to the mash diet. Nitrogen digestibility tended (P=0.10) to be greater in broilers fed the mash diet compared to pellet and re-ground pellet diets. Pellet-feeding reduced (P<0.05) starch digestibility compared to the mash diet and re-ground pellet. Pellet feeding also reduced (P<0.05) CAID of fat compared to mash diet but re-grinding the pellets restored fat digestibility. Pelleting reduced (P<0.05) the CAID of Ca and re-grinding the pellets further decreased (P<0.05) Ca digestibility. Pelleting had no influence on the CAID of P, but re-grinding the pellets resulted in lower (P<0.05) P digestibility than that of the mash and pelleted diets. Feeding intact pellets reduced (P<0.05) the AME of the diet compared to the mash diet and the depression was maintained in re-ground pellets. Based on the greater nutrient intake of broilers offered intact pellets coupled with the lack of positive effect of pellet feeding on digestibility of nutrients, it can be suggested that an enhanced feed consumption was primarily responsible for the better performance of broilers fed sorghum-based pellets.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effect of the Camelina sativa oil on the performance, essential fatty acid
           level in tissues and fat-soluble vitamins content in the livers of broiler
           chickens
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): Teresa Jaśkiewicz , Agnieszka Sagan , Iwona Puzio
      Camelina (Camelina sativa) oil (CO) is rich source of α-linolenic acid. The diet for broiler chickens was supplemented with camelina oil and it was compared with diets supplemented with soybean oil (SO) and rapeseed oil (RO). A total of 90 one-day-old Ross 308 broiler chickens were used for a 35-d study, and chickens were allocated to 15 cages and 6 broiler chickens/cage. Cages were randomly assigned to three dietary treatments with five cages per treatment. The temperature and humidity were controlled, and broiler chickens had continuous access to feed and water. No differences were observed for growth performance. The addition of CO to the diet increased the α-linolenic acid content of the muscle tissues and abdominal fat (P<0.001). The α-linolenic acid content in the thigh muscle fat was 9.96% of fatty acids (FA) in the CO group and 1.51% of FA in the RO group, and the α-linolenic acid content in the breast muscle fat was 4.12% of FA in the CO group and 0.57% of FA in the RO group. The type of oil added to the diet had no effect on the accumulation of vitamins A and E in the livers of broiler chickens. The results of growth performance indicated that CO is similar to SO and RO as a dietary component. However, the type of oil impacted the fatty acid profile. These results showed the usefulness of CO in producing food enriched with α-linolenic acid.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effects of abomasal starch infusion on body condition, nutrient
           digestibility, mRNA abundance of hepatic and subcutaneous adipose in
           lactating dairy cows
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): Yang Zou , Zhanshan Yang , Yongqing Guo , Shengli Li , Zhijun Cao
      An experiment was performed to assess the effects of starch infusion on the nutrient digestibility, mRNA abundance of gluconeogenesis and lipid metabolism in mid-lactating cows. Four multiparous Holstein cows fitted with permanent ruminal cannulas were arranged into a complete 4×4 Latin squares, abomasally infused starch solution at 0, 800, 1600, and 2400g/d for 15 days. Compared with control, starch digestibility was improved by starch infusion of 1600g/d (P<0.05). No difference was detected in body weight and BCS (P>0.05). Liver PEPCK-C mRNA abundance in 1600g/d starch infusion was significantly (P<0.05) higher than control and 2400g/d starch group. GLUT-4mRNA (P=0.12) tended to increase quadratically; the maximum abundance was in 800g/d infusion group; however, the minimum PPAR-gamma abundance was in 1600g/d starch infusion group (P=0.10). Overall, abomasally supplementation of different degrees of starch to mid-lactating cows could certainly be carried down to the intestine directly to ameliorate energy supplies, and therefore, transport to the subcutaneous adipose stored as lipid.


      PubDate: 2014-06-07T15:00:14Z
       
  • Effects of dietary sulfur source on rumen pH and hydrogen sulfide gas
           concentration
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): M.E. Drewnoski , C.J. Brasche , S.L. Hansen
      A variety of sources of S have been utilized to study S toxicity in cattle; however, it is unknown if these S sources have similar potential to produce ruminal hydrogen sulfide (H2S). The objective of this study was to evaluate the effects of different sources of dietary S commonly used in ruminant S toxicity research on ruminal pH and gas-cap H2S. Five cannulated steers were used in a 5×5 Latin square and fed 1 of 5 diets containing 0.49% S once daily at 1.3% of body weight (DM basis). Dietary S sources included ethanol co-products: dried distillers grains plus solubles (DDGS), condensed corn distillers solubles (CCDS), or inorganic sources: sulfuric acid (SA), sodium sulfate (SS), and calcium sulfate (CS). All diets contained 45% corn and 10% grass hay (DM basis). In the DDGS treatment, DDGS was included at 42% diet DM and contributed 0.40% S. In the non-DDGS treatments, DDGS was included at 21% diet DM and contributed 0.19% S to these diets. In the CCDS treatment, CCDS was included at 7% diet DM and contributed 0.19% S to the diet. For the inorganic treatments (SA, SS and CS) S sources contributed 0.17% S to the diet. In the non-DDGS diets, soyhulls were included to make up the balance of diet DM (15% diet DM for CCDS diet and 21% diet DM for the inorganic S source diets). Sampling of ruminal pH and H2S gas concentration occurred at 6h post-feeding. Diet pH (P<0.01; SEM±0.032) differed due to S source, with SA (3.93) having the lowest pH (P<0.01) whereas SS (4.79) and CS (4.79) were greatest (P<0.01), but did not differ (P=0.97). The co-product diets were intermediate, with DDGS (4.08) having a lower (P<0.01) pH than CCDS (4.18). However, ruminal pH at 6h post-feeding (SEM±0.076) was least (P<0.01) for CS (5.03), followed by SA (5.28) which was lesser (P≤0.05) than DDGS (5.40), SS (5.43), and CCDS (5.50) which did not differ (P≥0.09). There was no difference in S intake (P=0.31) or ruminal H2S concentration (P=0.62) among treatments. Even though dietary pH varied among treatments ruminal pH differences were minimal and no differences in ruminal H2S were observed, suggesting that results of experiments utilizing these different S sources to research S toxicity may be comparable.


      PubDate: 2014-06-07T15:00:14Z
       
  • Seasonal diet quality and metabolic profiles of steers grazing on
           Chihuahuan desert rangeland
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): M. Murillo-Ortiz , M. Mellado-Bosque , E. Herrera-Torres , O. Reyes-Estrada , F.O. Carrete-Carreón
      Four Angus steers (BW=350±3kg) with esophageal cannulae and four fitted with ruminal cannulas (BW=351±5kg) as well as fifteen steers of the same racial characteristics (BW=320±2kg), were used to evaluate seasonally across four years (2005–2009, excluding 2007) the nutritive quality of diet and the blood metabolites and insulin levels in grazing beef cattle a Chihuahuan desert rangeland. The diet consumed by grazing cattle during spring and winter was low quality because of crude protein (CP) was less than 70g/kg DM and neutral detergent fiber (NDF) higher than 720g/kg DM. Initial washing loss at time zero “A”, digestion rate “c”, effective degradability of NDF (EDNDF) and CP (EDCP), potential gas production (PGP), ruminal ammonia–nitrogen (NH3N), total volatile fatty acids (TVFA) propionate, butyrate, glucose (G), urea nitrogen (UN) and insulin were highest in summer compared to spring (P<0.05). In contrast, ruminal acetate concentrations and blood non-esterified fatty acids (NEFA) level were highest in spring as compared to summer (P<0.05). It was concluded that season of grazing had a marked influence on diet quality as well as in the blood metabolites and insulin levels in grazing beef cattle a desert rangeland.


      PubDate: 2014-06-07T15:00:14Z
       
  • Soybean meal replaced by slow release urea in finishing diets for beef
           cattle
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): P.D.B. Benedeti , P.V.R. Paulino , M.I. Marcondes , S.C. Valadares Filho , T.S. Martins , E.F. Lisboa , L.H.P. Silva , C.R.V. Teixeira , M.S. Duarte
      Eight crossbred steers (average body weight of 418kg) fitted with ruminal and abomasal cannula were used to evaluate the effects of replacing soybean meal (SBM) with slow-release urea (SRU) in beef cattle diets containing two concentrate levels. The experimental design included two 4×4 Latin squares, which were run simultaneously. Each Latin square received one level of concentrate [400 or 800g/kg on a dry matter (DM) basis]. Within each Latin square, the four replacement levels of soybean meal protein with slow-release urea were applied to the animals (0%, 33%, 66% and 100% of substitution on N basis). The DM intake as well as organic matter (OM) intake and crude protein (CP) intake decreased linearly (P<0.05) as SBM was replaced with SRU. Ruminal digestibility coefficient of OM tended to be greater (P=0.074) for the 40 % concentrate diet. DM and OM passage rate (k p ) were greater (P<0.05) on the 80% concentrate diet. A cubic effect (P<0.10) of SBM replacement with SRU on ruminal ammonia (NH3–N) concentration in relation to time was detected. A quadratic effect on pH was observed (P<0.10) when replacing SBM with SRU. Nitrogen intake, nitrogen excreted in the feces, nitrogen balance and efficiency of nitrogen use decreased linearly (P<0.10) as SRU increased in the diet, whereas the total nitrogen excreted in urine increased linearly (P=0.007). The production of microbial nitrogen and microbial efficiency were not affected by the experimental treatments (P>0.10). A lower intake of DM, OM, and CP was observed when cattle were fed SRU compared to SBM. However, the use of SRU did not change the digestibility and digestion rate (k d ) and k p of DM, OM, CP and neutral detergent fiber corrected for ash and protein (NDFap). In summary, SRU provides higher concentrations of NH3–N throughout a day than SBM in cattle fed low concentrate diets.


      PubDate: 2014-06-07T15:00:14Z
       
  • Use of faecal components as markers to estimate intake and digestibility
           of grazing sheep
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): E.B. Azevedo , C.H.E.C. Poli , D.B. David , G.A. Amaral , L. Fonseca , P.C.F. Carvalho , V. Fischer , S.T. Morris
      This research was carried out to evaluate the use of faecal components as markers to estimate intake and digestibility of Italian Ryegrass (Lolium multiflorum Lam.) of grazing sheep. The research had two phases. In Phase 1 seven indoor experiments were carried out using individual metabolic cages with 16 lambs in each experiment (four treatments with four animals each). Three phenological stages of the pasture (vegetative, pre-flowering and flowering) were evaluated and four different allowances of Italian Ryegrass, collected by grab sampling daily, of 1.5, 2.0, 2.5kg of dry matter/100kg of live weight and ad libitum. The indoor experimental design was completely randomized and the experiments were grouped according to the phenological stages. Organic matter intake (OMI, g/day), total daily production of faeces, faecal crude protein amount (fCP, g/day), faecal crude protein concentration (fCPc, g/kg of organic matter), faecal acid detergent fibre amount (fADF, g/day), faecal acid detergent concentration (fADFc, g/kg of organic matter) and organic matter digestibility (OMD) were assessed in the indoor experiment. In Phase 2, male sheep were used in two grazing experiments to graze Italian Ryegrass under different management conditions, which were herbage allowance, pasture phenological stage and rotational or continuous system. This phase was designed to validate the equations previously obtained. The stocking rate was controlled according the treatment defined, and the herbage mass, sward height, herbage and faecal chemical composition, OMI and OMD were measured. In Phase 1 significant linear regression equations were found between OMI and fCP in each phenological stage (P<0.05). The intake equations were compared by contrasts analysis and found to be different (P<0.001) between phenological stages, confirming the need to use the data separately by maturity stage. Two equations (simple and multiple hyperbolic) were tested for the relationship between OMD and fCPc, and the multiple hyperbolic, which includes fCPc and fADFc showed best accuracy. In Phase 2 the regression between the actual and estimated had a correlation coefficient of 0.94 and relative prediction error of 9.28%, showing the feasibility of using the generated equations.


      PubDate: 2014-06-07T15:00:14Z
       
  • Kinematics as objective tools to evaluate lameness phases in multiparous
           sows
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): C.M. Mohling , A.K. Johnson , J.F. Coetzee , L.A. Karriker , C.E. Abell , S.T. Millman , K.J. Stalder
      Lameness has been ranked as the third most common reason for culling sows, comprising 15% of the culls marketed in the U.S. Producers assess sow lameness using subjective evaluation, which have been shown to be variable in their application. Objective empirical tools to measure sow lameness on farm are required. Therefore, the purpose of this study were to evaluate the embedded force plate and the GAITFour gait analysis walkway system as objective assessment tools to discriminate between sound and lame phases in multiparous sows. Twenty-four mixed parity crossbred sows were anesthetized and injected with Amphotericin B in the distal interphalangeal joint of both claws of one hind hoof to induce transient lameness. Kinematic data was collected on D−1, D+1 and D+6 relative to induction (D0). For the embedded force plate, weight distributions on each hoof were collected. Gait analysis measures collected were stride time (defined as the time (s) between 2 successive footfalls by the same hoof), stride length (defined as the distance (cm) between 2 sequential footfalls from the same hoof), maximum pressure (defined as the greatest amount of weight (kg/cm2) placed on a single hoof) and stance time (defined as the duration of time (s) the sensors were activated by a hoof in a single stride). For the embedded microcomputer-based force plate system weight placed on the induced hoof decreased on D+1 when compared to D−1 (P<0.0001). For the GAITFour® pressure mat gait analysis walkway system, stride time increased on D+1 for all hooves, stride length decreased on D+1 compared to D−1 and maximum pressure placed on the induced hoof decreased on D+1 compared to baseline levels (P<0.05). Stance time increased for all sound hooves on D+1 compared to D−1 (P<0.05). In conclusion, the embedded force plate and GAITFour walkway system all demonstrated differences for mature sows during sound and most lame phases indicating promise as objective tools for use on farm.


      PubDate: 2014-06-07T15:00:14Z
       
  • Productive and reproductive performance of first lactation purebred
           Holstein versus Swedish red &amp; white×Holstein in central
           Argentina
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): M. Piccardi , D. Pipino , G.A. Bó , M. Balzarini
      The aim of this work was to compare productive and reproductive performance between pure Holstein (H) and Swedish Red & White×Holstein crossbred (SRB/H) in first lactation dairy cows from the central region of Argentina. This study included 450 lactations from a commercial dairy of central-southern Argentina. The differences in mean daily milk yield, days to first breeding (DFB) and number of services per pregnancy (NS/P) between genotypes were evaluated. A Cox proportional hazard regression model was fitted to evaluate the breed effects on days open (DO) and adjusting by calving season and calving year. Days open were estimated trough survival curves for H breed and SRB/H crossbred using Kaplan–Meier method. Finally, average lactation curves were modeled for each genotype using a non-linear mixed model. Daily milk yield was not significantly different between genotypes. However, the cumulative 305-d yield and peak milk yield for pure H was higher than for SRB/H. Days to first breeding was lower for SRB/H than pure H. The NS/P was higher for pure H than for SRB/H. Regarding DO, SRB/H breed had 1.00–1.71 higher likelihood to become pregnant than pure H. Days open of 50% of pure H was 30 d higher than for SRB/H. The results showed that SRB/H crossbred were superior to pure H in terms of reproductive performance but inferior in terms of productive performance. Further studies may help to determine if the economics of dairying justifies the use of crossbreeding as a herd fertility enhancing tool.


      PubDate: 2014-06-07T15:00:14Z
       
  • Comparisons of carcass and meat quality among rabbit breeds of different
           sizes, and hybrid rabbits
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): E. Tůmová , Z. Bízková , V. Skřivanová , D. Chodová , M. Martinec , Z. Volek
      The aim of the present study was to evaluate the differences in carcass composition, meat quality characteristics, and muscle fibre characteristics among rabbits of different sizes and of different breeds. The present study was performed using 96 rabbits (12 rabbits per group) at the age of 90 days, including seven pure breeds and one commercial hybrid. The included rabbit breeds were as follows: the giant breed Moravian Blue (MB); the medium breeds Czech White (CW), Czech Spotted (CS), Czech Solver (CSo), and Moravian White of Brown Eye (MW); the small breeds Czech Black Guard Hair (CB) and Czech Gold (CG); and the hybrid Hyplus rabbits (PS 19×PS 39). The slaughter weights were significantly (P<0.001) affected by the breed. Comparisons of the dressing out percentage showed significant differences (P<0.001) among groups, and the lowest dressing out percentage was observed in the small breed CB (56.7%). The lowest values for the hind part percentage, hind leg percentage and hind leg meat percentage were in the medium breed CS (50.1%, 28.2% and 21.6% respectively). The results of the loin chemical composition assay revealed differences among the groups in crude protein (P<0.001), fat (P<0.001) and cholesterol (P<0.05) contents and in the hind leg meat differences in crude protein (P<0.001) and fat contents (P<0.05). The highest (P<0.05) loin cholesterol contents (53.4mg/100g), hind leg fat (3.59%) values were observed in the medium breed CS, which corresponded with the highest perirenal fat content (2.98%). For both types of muscle fibres (βR and αW), the smallest (P<0.001) cross-sectional areas, diameters and perimeters were found in Hyplus rabbits. Good results of CW rabbits in carcass composition show that this breed might be used for commercial production.


      PubDate: 2014-06-07T15:00:14Z
       
  • Editorial Board
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165




      PubDate: 2014-06-07T15:00:14Z
       
  • Effect of single nucleotide polymorphisms in GH gene promoter region on
           carcass traits and intramuscular fatty acid compositions in Japanese Black
           cattle
    • Abstract: Publication date: July 2014
      Source:Livestock Science, Volume 165
      Author(s): Haruna Sugita , Astrid Ardiyanti , Shoko Yokota , Shinichi Yonekura , Takuji Hirayama , Noriaki Shoji , Eri Yamauchi , Keiichi Suzuki , Kazuo Katoh , Sang-Gun Roh
      Previous studies demonstrated that single nucleotide polymorphisms (SNPs) in exon 5 of the bovine growth hormone (GH) gene affected live weight and carcass traits in Japanese Black cattle. The aims of the present study were to identify SNPs in the promoter region of the GH gene and to analyze their effects on carcass traits and intramuscular (i.m.) fatty acid compositions in Japanese Black cattle (511 steers and 252 heifers; 30.5±0.1 months old). SNPs in the promoter region of the GH gene were detected at g.253, g.303, and g.502 and classified into 4 haplotypes, i.e. haplotype P (T-C-C), Q (C-C-C), R (C-C-T), and S (T-T-C). Among genotypes at g.253, genotype TT had the highest carcass weight (CW), rib thickness (RT), and C14:0 and C16:1 contents, but the lowest C18:0 content. The rib eye area (REA) in genotype TT was higher compared with that in genotype CC. Genotype CC had the lowest C16:0 content and higher C18:1 and MUFA contents compared with those in genotype TT. Among genotypes at g.303, genotype CC had the highest C14:0, C16:0, and C16:1 contents, but the lowest C18:1 content. Genotype TT had the lowest CW and RT, but the highest C18:0 content. At both locations, the heterozygous animals showed intermediate values for most traits. Regarding GH promoter diplotypes, diplotype PP had higher CW, C16:0, and C16:1 than diplotype SS and tended to have the lowest C18:0 compared with diplotype QQ and SS. In conclusion, SNPs at g.253 and g.303 in the GH promoter region affects carcass traits in Japanese Black cattle.


      PubDate: 2014-06-07T15:00:14Z
       
  • Efficacy of dimethylglycine as a feed additive to improve broiler
           production
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): I.D. Kalmar , M.W.A. Verstegen , D. Vanrompay , K. Maenner , J. Zentek , C. Iben , R. Leitgeb , A. Schiavone , L. Prola , G.P.J. Janssens
      Dimethylglycine (DMG) is a naturally occurring glycine derivative, which is useful as additive to broiler diets as it improves nutrient digestibility and reduces the development of broiler ascites syndrome. This study evaluated the efficacy of dietary DMG to enhance performance of broiler chickens. Three trials were conducted to evaluate the effect of dietary supplementation with 1g Na DMG/kg on growth performance and carcass characteristics. In Trial 1, the effect of sex was also assessed in a 2×2 factorial arrangement of treatments. In Trials 1 (Germany), 2 (Austria), and 3 (Italy), each treatment consisted of 6, 12, and 11 replicate pens with 20, 15, and 16 one-day-old broiler chickens per pen, respectively. Dietary DMG supplementation resulted in improved feed conversion ratio (FCR) in the starter phase by 8.8% (P=0.004), 6.4% (P=0.001), and 4.8% (P=0.006) compared with the control diet in Trials 1, 2, and 3, respectively. The overall FCR improved in broiler chickens fed the diets supplemented with DMG by 3.8% and 4.1% in Trials 1 (P=0.007) and 3 (P=0.006), respectively. In addition, final body weight increased by 5.5% (P=0.001) in Trial 2 and production value improved by 6.8% (P=0.015) in Trial 1 by dietary DMG supplementation. Mortality in all trials was similar between dietary treatments. In all 3 trials, cold carcass weight and total meat yield were as well similar between broiler chickens fed the control and DMG diets. In Trial 1, dietary DMG had no effect on breast meat yield in male broiler chickens, but it increased breast meat yield in female broiler chickens (diet×sex, P=0.004). Organoleptic quality of roasted breast meat assessed only in Trial 2 was not affected by dietary treatments. In conclusion, dietary supplementation of DMG at 1g Na DMG/kg can considerably improve s production performance in broiler chickens.


      PubDate: 2014-04-27T22:53:02Z
       
  • Nitrogen balance, blood metabolites and milk fatty acid composition of
           dairy cows fed pomegranate-peel extract
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): M.J. Abarghuei , Y. Rouzbehan , A.Z.M Salem , M.J. Zamiri
      An experiment was carried out to determine the effect of pomegranate peel extract (PPE) on nitrogen balance, blood parameters and the milk fatty acid profile of dairy cows. Four Holstein cows were used in a 4×4 Latin square design with 28-d periods and 4 treatments: PPE0 (no extract), PPE400 (400ml PPE/cow/d), PPE800 (800ml PPE/cow/d) and PPE1200 (1200ml PE/cow/d). Nitrogen balance, blood parameters and the milk fatty acid profile were measured. Determination of secondary metabolites showed its high content of aqueous fraction, total phenolics and total tannin with reasonable content of saponins. Outputs of N in milk were quadratically increased (P=0.044) by inclusion of PPE at 400 and 800ml PPE/cow/d in the diet. Blood cholesterol (quadratic effect, P=0.043), blood urea nitrogen (linear effect, P=0.047) and milk urea nitrogen (quadratic effect, P=0.0008) concentrations decreased with adding PPE. Supplementation with PPE quadratically lowered total saturated fatty acid (P=0.005), proportions of C12:0 (linear effect=0.040), C16:1c9 (quadratic effect, P=0.011), C18:0 (linear effect, P=0.083, quadratic effect, P=0.011) and ω6/ω3 (quadratic effect, P=0.007). Amount of C18:3c (n-3) (linear effect, P=0.046), DHA (C22:6) (quadratic effect, P=0.009) and EPA (C20:5) (quadratic effect, P=0.012) were increased by inclusion of PPE. Adding PPE lowered blood cholesterol, blood urea nitrogen and milk urea nitrogen. Milk from cows fed PE had significantly lower total saturated fatty acid, desirable ω6/ω3 ratio and higher content of EPA and DHA.


      PubDate: 2014-04-27T22:53:02Z
       
  • The effect of fat type and l-carnitine administration on growth, feed
           digestibility and blood metabolites of growing Afshari lambs
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): A.D. Foroozandeh , H.R. Amini , G.R. Ghalamkari , M. Shahzeydi , S.M. Nasrollahi
      This study was conducted to evaluate the effect of fat type and l-carnitine supplementation on feed intake, nutrient digestibility, growth, and blood metabolites in growing Afshari lambs. Twenty-four-male lambs with an initial body weight of 16±0.4kg were used in a completely randomized design with a 2×2 factorial arrangement of fat type with or without supplemental carnitine in an 84-day feeding period. The diets were isoenergetic and isonitrogenous. Soybean oil or a commercial Ca-protected fat were included at 4% of the DM of diet, each with or without 100mg l-carnitine top dressed per kg of diet. Initial weight was equalized across treatments. At the end of experiment, blood was sampled from each lamb and concentrations of serum glucose, BUN, total protein, triglyceride, total cholesterol, HDL, and LDL were determined. There was no interaction between fat type and carnitine administration on feed intake, nutrient digestibility and growth. Fat type did not affect feed intake, but lambs fed soybean oil had greater DM and EE digestibility (P<0.05), and tended to have higher CP digestibility. Supplemental l-carnitine did not affect feed intake, but improved EE digestibility (P<0.01) and tended to improve CP digestibility (P=0.10). Although fat type did not affect growth of lambs, l-carnitine administration tended (P=0.13) to improve body weight and ADG, thus improving FCR (P<0.05). Fat type interacted with l-carnitine administration for cholesterol and LDL concentration in blood; l-carnitine administration significantly decreased them only for the soybean oil diet (P<0.05). Lambs fed with soybean oil, compared with Ca-protected fat, had more (P<0.05) total protein and BUN and tended (P=0.11) to have lower triglyceride concentrations in the blood. Under conditions of the current study l-carnitine might improve growth, dietary fat digestibility, and blood metabolites of lambs fed diets with supplemented fat. Supplementing different fat types had a minimal effect on responses of lambs.


      PubDate: 2014-04-27T22:53:02Z
       
  • Repeated hormonal treatment and laparoscopic ovum pick-up followed by in
           vitro embryo production in goats raised in the tropics
    • Abstract: Publication date: Available online 19 April 2014
      Source:Livestock Science
      Author(s): Deisy J.D. Sanchez , Carlos H.S. Melo , Joanna M.G. Souza-Fabjan , Francisco C. Sousa , Amanda A. Rocha , Iana S. Campelo , Dárcio I.A. Teixeira , Alexsandra F. Pereira , Luciana M. Melo , Vicente J.F. Freitas
      The objectives of this study were to evaluate the ovarian response of oocyte donor goats which underwent seven repeated ovulation hormonal treatments and laparoscopic ovum pick-up (Experiment 1), and to compare the in vitro production (IVP) of embryos from goats hormonally treated for eighth times to IVP of embryos from females with a single hormonal treatment (Experiment 2). In Experiment 1, 12 goats were subjected to 7 repeated hormonal treatments and laparoscopic ovum pick-up (LOPU) every 2 to 3 weeks, and the following variables were recorded: number and size of punctured follicles, number of recovered cumulus-oocyte complexes (COCs), recovery rate and COCs quality. In Experiment 2, IVP of embryos from goats hormonally treated for eighth time (repeated-treated group, RT) was compared with IVP of embryos from 10 other goats with only one hormonal treatment (single-treated group, ST). In this step, in addition to variables observed in Experiment 1, cleavage, blastocyst rates at Days 7 and 8 of culture, hatched rate and the number of blastomeres per embryo were also evaluated. In Experiment 1, when comparing LOPU sessions, no difference (P>0.05) was verified for number of punctured follicles, number of recovered COCs and recovery rate. However the percentage of large follicles was different (P<0.05) between LOPU 1 (27.7±10.5) and 7 (12.4±12.1), the latter being similar to sessions 2 (13.9±10.9), 3 (13.4±7.9), 4 (13.2±10.7), 5 (22.4±14.7) and 6 (17.7±15.8). The percentage of COCs suitable for IVM was lower (P<0.05) for LOPU 1 (80.6%), 2 (82.4%) and 3 (79.7%) than LOPU 6 (91.3%) and 7 (95.2%). In Experiment 2, total number of follicles aspirated/goat and total number of COCs recovered were similar (P>0.05) for RT (18.0±5.8 and 12.3±3.7, respectively) and ST (19.4±7.8 and 15.8±7.7, respectively) groups. However, the recovery rate was lower (P<0.05) in the RT vs the ST group (68.5 and 81.4%). The percentage of small, medium and large follicles was similar (P>0.05), respectively, for RT (28, 55 and 17%) and ST (20, 65 and 15%) groups. The percentage of COCs suitable for IVM had no difference (P>0.05) for RT (96.6%) and ST (93.7%) groups. No significant difference was observed between RT and ST groups for: cleavage rate (68.6 vs 67.0%), blastocyst rate at Day 7 (27.9 vs 31.8%) and 8 (27.9 vs 34.1%), hatched rate (33.3 vs 53.3%), and blastomeres/embryo (252.9 vs 229.8). In conclusion, in goats raised in tropical climate, the IVP of embryos from oocytes obtained by LOPU could to be an efficient and suitable method for rapid propagation of genetically superior animals. Donor goats, even after repeated hormonal treatments followed by LOPU, maintained the ovarian response for oocyte and embryo production, becoming close to reality the term “oocyte permanent donors”.


      PubDate: 2014-04-27T22:53:02Z
       
  • Association and expression analysis of porcine ACLY gene related to growth
           and carcass quality traits in Italian Large White and Italian Duroc breeds
           
    • Abstract: Publication date: Available online 18 April 2014
      Source:Livestock Science
      Author(s): Roberta Davoli , Silvia Braglia , Martina Zappaterra , Carla Redeghieri , Marco Comella , Paolo Zambonelli
      Lipogenesis is a complex metabolic process that involves many enzymes: one of them, ATP citrate lyase (ACLY) is related in fatty acid biosynthesis. The aim of this study was to find association between two Single Nucleotide Polymorphisms for ACLY porcine gene and the most important productive traits and to verify the expression level of this gene in Italian Large White and Italian Duroc pigs in muscle and backfat tissues. The first SNP ACLYc.NM_001105302 2956T>C lies in a portion of the coding region corresponding to human exon 25 while the second SNP ACLY c.*523T>C is located in the porcine ACLY gene 3′ UTR. In Italian Large White pigs SNP ACLYc.NM_001105302 2956T>C shows an association with Average Daily Gain, and CC genotype is the most favourable to animal growth, whereas the same SNP in Italian Duroc pigs is not associated with analysed traits. This difference in association results may be a plausible evidence of the divergent genome background between Italian Large White and Italian Duroc breeds, as reported in recent studies. On the other hand c.*523T>C SNP shows concordant association results, as in both breeds CC animals display the best values for the analysed carcass traits. Moreover, we evaluated in both breeds ACLY gene expression level in skeletal muscle and backfat. Italian Duroc pigs, according to their elevated marbling, have the highest ACLY gene expression in muscle, while Italian Large White pigs present the highest transcription level in backfat tissue. Furthermore ACLY expression is not influenced by the two studied polymorphisms, suggesting that these mutations do not affect gene transcription but might be in linkage disequilibrium with the causal mutation. In conclusion ACLY might be considered as new biomarker for genetic improvement schemes aimed to modulate the fat content, in carcass and in muscle.


      PubDate: 2014-04-27T22:53:02Z
       
  • Estimation of methane emission using the CO2 method from dairy cows fed
           concentrate with different carbohydrate compositions in automatic milking
           system
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): M.N. Haque , C. Cornou , J. Madsen
      Two concentrates (MELK and VEM) with two different carbohydrate compositions were supplemented during milking in an Automatic Milking System (AMS). The objectives of this study were to estimate the effect of the concentrates on CH4 emission from dairy cows and to investigate the precision of the CO2-method when measuring in an AMS for different length of time. Holstein cows (n=36) were used with mean body weight of 660kg (SD=75.13) and average milk production of 31.7kg (SD=8.98), mixed parity and mixed lactation. Cows were allocated in two groups (n=18). After an adaptation period (period 1), each group received either 100% MELK (More Energy Lactating Cows; a newly introduced feeding system) or 100% VEM (Feed Value System for milk production) during periods 2 and 3. Besides, both groups were fed the same Total Mixed Ration (TMR) ad libitum in the stable. Air samples in the AMS from a point near the cows head were analysed every 20s using the Gasmet equipment based on Fourier Transform Infrared (FTIR) Spectroscopy Technique. The equipment ran continuously for 15 days over the three measurement periods (5 days×3 periods) with a 14 days waiting time in between the periods. Individual records of the CH4 and CO2 concentrations in the cows breath was calculated after subtracting the CH4 and CO2 concentrations in the stable air from the measured concentrations. The CH4:CO2 ratio was then multiplied with the calculated total CO2 production by the individual cows to get the quantitative CH4 production. Milk production and total dry matter intake (DMI, kg/day) were very similar in the two groups. The supplemented concentrate was allocated according to the individual milk yield and the intake ranged from 1.60 to 7.30kg/day in MELK cows and from 2.06 to 7.20kg/day in VEM cows. No significant difference was found for CH4 production in MELK and VEM groups over the three periods. A linear positive relation between the CH4 (g/day) and energy corrected milk (ECM, kg/day) production and the feed intake (DMI, kg/day) was observed for the entire period. The calculated CO2 and CH4 production were very similar in the two groups throughout the entire measurement period. The analysis of the precision of the CO2-method, using a 95% significance level, indicated that showing a difference of 9 or 5% in methane production requires a measuring period of 5 or 15 days, respectively, when using 18 cows per group. The study shows no effect of a limited change in supplementation of starch and sugar on CH4 production through feeding concentrates MELK or VEM in the AMS. To obtain an effect of changing the carbohydrate composition of the diet on the CH4 production, it is likely that a larger change in the diet is necessary. This can only efficiently be done by changing the TMR part of the diet.


      PubDate: 2014-04-27T22:53:02Z
       
  • Can milk fat changes be predicted from nutrient flows in dairy cows'
           Design and evaluation of an empirical model
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): G. Maxin , J.L. Peyraud , P. Nozière , H. Rulquin , F. Glasser
      Most of the current feed evaluation systems used to estimate dairy cow requirements and formulate diets cannot predict the effects of dietary changes on milk composition, in particular on milk fat content (MFC) and milk fat yield (MFY) responses. Dietary changes alter dairy cow MFC and MFY through modifications in the supply of nutrients, which act as precursors or inhibitors of mammary fat synthesis. Taking into account the supply of nutrients could allow feed evaluation systems to predict milk composition responses to dietary changes. We described an empirical model based on nutrient flows to predict MFC and MFY responses to dietary changes. This model was built by coupling a set of published empirical equations estimating nutrient flows (acetate, propionate, butyrate, glucose and digestible protein) from dietary characteristics and the measured ruminal VFA proportions to another set of equations estimating the response of milk fat to the supply of these nutrients. The model was evaluated by comparing the predicted and observed MFC and MFY responses on three databases derived from published feeding studies in dairy cows. The databases compiled published trials involving a change in the forage-to-concentrate ratio (‘F:C ratio’ sub-database), a change in the carbohydrate source (‘CHO source’ sub-database) or a change in both F:C ratio and CHO source (‘ratio and source’ sub-database). Overall, the current version of the model did not accurately predict milk fat responses: the model did not enable to explain the MFC and MFY responses in the ‘CHO source’ sub-database (P>0.10 and R 2=0.02); in the ‘F:C ratio’ sub-database, agreement between observed and predicted responses was better (the slopes were not different from unity and were respectively 0.84 and 0.94 for MFC and MFY), but R 2 were low (R 2=0.36 for MFC and R 2=0.43 for MFY). In the ‘ratio and source’ database, MFY was quite correctly predicted (the slope was 0.93 and R 2=0.42), but not the MFC responses (P>0.10 and R 2=0.01). The mean errors of prediction for MFC were 2.61, 3.79 and 3.55g/kg, respectively in the ‘F:C ratio’, ‘CHO source’ and the ‘ratio and source’ sub-databases. The effects of several interfering factors related to cows, diets or experimental conditions were tested to explain differences between observed and predicted responses in each sub-database. They enabled to identify several potential sources of bias in the model: especially, bias in estimation of OM digestibility, bias in estimation of glucose effects, lack of the effects of fatty acids in the model. These constitute interesting ways to improve the model.


      PubDate: 2014-04-27T22:53:02Z
       
  • Using archaeol to investigate the location of methanogens in the ruminant
           digestive tract
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): C.A. McCartney , I.D. Bull , R.J. Dewhurst
      The quantification of archaeol, a methanogen membrane lipid, may provide an alternative method to estimate methanogen abundance. The focus of this study was to determine the location of methanogens in the ruminant digestive tract using this biomarker. Archaeol was quantified in samples obtained from four lactating cows with rumen cannulae that grazed on either white clover (WC) or perennial ryegrass (PRG) in a changeover design study with three 3-week periods. Faeces were collected over the final 5d of each period and total rumen contents (TRC) were obtained on the final 2 days (day 1: 9am; day 2: 3pm). Solid-associated microbes (SAM) and liquid-associated microbes (LAM) were also isolated from the TRC. Concentrations of archaeol in the TRC showed a significant diet by time interaction, which may be related to diurnal grazing patterns and different rumen conditions associated with PRG or WC diets. There was significantly more archaeol associated with SAM than LAM, which may reflect difficulties of methanogen proliferation in the liquid phase. Faeces had higher concentrations of archaeol than SAM and LAM which was unexpected, although, losses of methanogens may have occurred during isolation (i.e., attachment to protozoa and very small particles), or the methanogens associated with SAM may have been underestimated. There was no significant relationship between faecal and TRC archaeol concentrations. Finally, there was a significant positive relationship between rumen pH and concentrations of archaeol in SAM and LAM, which may be caused by pH and/or WC diet effects. In conclusion, archaeol is potentially a useful alternative marker for determining the abundance of methanogens in the ruminant digestive tract. This work has also highlighted the difficulties associated with methanogen quantification from microbial isolates, and the need for more representative rumen sampling in future studies.


      PubDate: 2014-04-27T22:53:02Z
       
  • Residual feed intake as selection tool in South African Bonsmara cattle
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): Y. Steyn , E. van Marle-Köster , H.E. Theron
      In South African Bonsmara cattle, feed conversion ratio (FCR) is mostly used as a measure of feed efficiency in selection programs but has the disadvantage of being a ratio trait and unfavourably correlated to weight and mature size. Residual feed intake (RFI) overcomes both these disadvantages. The purpose of this study was to evaluate RFI as a potential trait in a selection programme by determining its correlations with growth related traits as well as other efficiency traits. Data of 5981 Bonsmara bulls that participated in centralised growth tests was analysed. In this study, RFI was calculated within contemporary groups of more than ten animals. The h 2 for RFI, FCR and KR were 0.27±0.02, 0.23±0.02 and 0.18±0.02 respectively. The genetic correlation between RFI and FCR, and RFI and KR were 0.65±0.04 and 0.12±0.07 respectively. Correlations approaching zero were estimated between RFI and shoulder height (SH), body length (BL), scrotal circumference (SC), average daily gain (ADG), weaning weight (WW) and metabolic mid-weight (MMW), and a strong correlation of 0.79±0.03 with daily feed intake (DFI). This study shows sufficient genetic variation for RFI to be considered by the Bonsmara breed as a measure of feed efficiency and confirms its independence from growth and size traits.


      PubDate: 2014-04-27T22:53:02Z
       
  • Construction of a cDNA library and identification of genes from Liaoning
           cashmere goat
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): Mei Jin , Nian Liu , Songxue Yuan , Jun Piao , Fengqin Zhao , Yangle Qu , Tingting Zhang , Yanjie Wang
      We constructed a skin cDNA library of the Liaoning cashmere goat during follicle anagen. The recombination was over 89%. A total of 1986 expressed sequence tags (ESTs) were sequenced. After assembly, 1126 ESTs that were homologous to functionally characterized or hypothetical proteins were obtained. BLASTX searches found 904 ESTs that had strong matches to known proteins. More than 50% of the ESTs were similar to proteins that were annotated either as related to enzyme/catalytic activity (26.5%) or as being involved in cell activities, such as growth differentiation, proliferation, apoptosis, transportation, and signal transmission (25.9%). 1.2% of the ESTs were similar to proteins that were related to hair/hair follicle. By analyzing the structure of the unisequences, 81 full-length cDNA clones were identified, none of which had yet been identified in goat. We selected two full-length cDNA clones with predicted proteins, which were similar to dimethyladenosine transferase 1-like (DIMT1L) and coatomer protein complex, subunit zeta (ζ-COP). An analysis of the tertiary structure of the DIMT1L homolog showed that it had a methyltransferase domain. The ζ-COP was a short chain and had a simple tertiary structure. In order to study DIMT1L and ζ-COP genes expression, the semi-quantitative RT-PCR was used to detect whether DIMT1L and ζ-COP genes were expressed in heart, liver, spleen, lung, kidney tissues and in situ hybridization (ISH) to detect DIMT1L and ζ-COP genes expression location. Both DIMT1L and ζ-COP genes had high expression levels in heart and skin, and low levels in liver, kidney, lung and spleen. Moreover, DIMT1L and ζ-COP genes had a strong expression in the inner root sheath of the primary hair follicles (PF) and the secondary hair follicles (SF). The ζ-COP gene also had a strong expression in the surrounding tissue. In conclusion, we have successfully constructed a skin cDNA library from Liaoning cashmere goat during follicle anagen and characterized two genes. The cDNA library could become a valuable source to study the biology genetic characteristics of Liaoning cashmere goat and may provide an important platform for protecting genomic resources and improving the breed.


      PubDate: 2014-04-27T22:53:02Z
       
  • Enteric and manure-derived methane emissions and biogas yield of slurry
           from dairy cows fed grass silage and maize silage with and without
           supplementation of rapeseed
    • Abstract: Publication date: Available online 18 April 2014
      Source:Livestock Science
      Author(s): A.L.F. Hellwing , M.R. Weisbjerg , H.B. Møller
      The aim of this study was to investigate the effect of three different dietary strategies on milk production and composition, enteric CH4 emissions, slurry storage losses of CH4 and total emissions of CH4 with and without biogas production. Fifty-four cows were allocated to three diets according to parity and days in milk. Two diets were based on maize silage with (MS+) or without (MS-) supplementation of crushed rapeseed, and the third diet was based on late cut grass silage without supplementation of crushed rapeseed (GS-). Dry matter intake, milk yield and composition were measured. Enteric methane emissions were measured on 24 cows by means of indirect calorimetertri. Slurry was collected the last 10 days of the experiment. Ultimate biogas yield, CH4 emissions at different storage temperatures and yield in a thermophilic biogas digester were determined for the three slurries. Dry matter intake was 22.5kg/day on MS- and MS+ which was significantly higher than the 20.7kg/day on GS-. Yield of energy corrected milk (ECM) was 2.8 and 2.5kg higher on MS+ compared with GS- and MS-, respectively. Enteric CH4 emissions related to dry matter intake or gross energy intake were highest for GS-. Supplementation of crushed rapeseed did not affect enteric CH4 emissions. Ultimate biogas yield and yield of CH4 in the digester were higher for MS+ and MS- than for GS-. Storage emissions from slurry increased with increasing storage temperature. The average total CH4 per kg ECM for the three treatments (mean±standard deviation) was 25.3±2.5, 26.8±3.3 and 29.0±4.2L CH4/kg ECM if manure was stored at 10°C, 15 °C or 20 °C, respectively. When the slurry was digested in a laboratory scale biogas plant, the lowest total CH4 emissions per kg ECM were observed for MS+ (20.5L CH4/ECM) and the highest for GS- (24.3L CH4/ECM) corresponding to the enteric emissions of CH4. It was found that MS+ had a higher yield and a lower milk fat concentration than MS- and GS-. Although MS+ had a lower milk fat concentration, the ECM yield was significantly higher for MS+ than for the two other diets. It was furthermore concluded that feed ration induced reductions in enteric methane emissions might be counteracted or complemented by changed methane emissions from slurry storage. The slurry biogas yield was highest (per kg ECM) from cows fed MS+ which also gave the lowest total methane emissions per kg ECM.


      PubDate: 2014-04-27T22:53:02Z
       
  • Selection for morphology, gaits and functional traits in Lusitano horses:
           II. Fixed effects, genetic trends and selection in retrospect
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): A.A. Vicente , N. Carolino , J. Ralão-Duarte , L.T. Gama
      Mixed model procedures were used to analyze morphology and gaits records collected in about 18,000 Lusitano horses from 900 studs, over a period of 43 years, and functional records collected since 1998, to carry-out a critical assessment of the fixed effects and selection practices followed in this breed. Fixed effects considered in the analysis of morphology (head/neck, shoulder/withers, chest/thorax, back/loin, croup, legs and overall impression), gaits and final score (computed by summing partial morphological and gaits scores) were stud, year, sex, inbreeding and age. Functional traits analyzed were the scores obtained in working equitation dressage (WEDT) and maneability (WEMT) trials and in classical dressage (CD), where fixed effects were event, level of competition, sex, inbreeding and age. Phenotypic trends were moderate over the period analyzed, with a slight increase in height at withers, and a decline in final score. Nevertheless, differences among years were mostly environmental. Males received lower scores for almost all morphological and gaits traits except croup, with a difference of about −1.7 points for final score relative to females. Sex differences were small for functional traits, with general advantage of males in WEMT and CD, and a disadvantage in WEDT. Considerable differences were detected among studs, especially in their environmental effects but also in mean estimated breeding value (EBV), for morphology, gaits and functionality. The environmental effect of competition level in CD resulted in a progressively lower scoring as the competition became more difficult, while for WEMT the pattern was opposite and differences were minor for WEDT. Inbreeding depression was observed for all morphological and gait traits, but the magnitude of its impact was very small for all traits analyzed, never exceeding −0.1% of the mean per 1% inbreeding. Still, for functional traits the effect of inbreeding was negligible. The EBV for morphology, gaits, WEMT and WEDT show considerable variability, indicating that selection can be effective. For CD, however, the distribution of EBV was narrower. The genetic trend was positive but moderate for all traits, and it was slightly higher for head and neck, overall impression, gaits and final score. As a percentage of the mean, these traits and working equitation trials showed the highest responses, which in the best cases did not exceed 0.2% of the mean per year. Genetic selection differentials and the corresponding selection intensities were very modest for all traits analyzed, with a slightly higher intensity in sires when compared to dams.


      PubDate: 2014-04-27T22:53:02Z
       
  • Editorial Board
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164




      PubDate: 2014-04-27T22:53:02Z
       
  • Editorial Board
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164




      PubDate: 2014-04-27T22:53:02Z
       
  • Selection for morphology, gaits and functional traits in Lusitano horses:
           I. Genetic parameter estimates
    • Abstract: Publication date: June 2014
      Source:Livestock Science, Volume 164
      Author(s): A.A. Vicente , N. Carolino , J. Ralão-Duarte , L.T. Gama
      Genetic parameters were estimated for morphology, gaits and functional traits in Lusitano horses by uni- and multivariate animal models. Morphological traits considered in the analyses were partial scores attributed to up to 18,076 horses at the time of registration in the studbook and included head and neck, shoulder and withers, chest and thorax, back and loin, croup, legs and overall impression, plus a final score computed by summing the partial morphological scores and the gaits score. The functional traits considered were the scores obtained in the dressage and maneability trials of working equitation (WE, about 1500 records by 200 horses), and classical dressage (12,131 records by 759 horses). The heritability (h 2) estimates for all partial morphological scores ranged between 0.12 and 0.18, except for legs (0.07). The h 2 for final score, height at withers and gaits was 0.18, 0.61 and 0.17, respectively, while for WE dressage trial and classical dressage it was 0.32 and for WE maneability trial it was 0.18. The genetic correlations (r G ) of final score with the different partial scores were generally high (0.56–0.95), while among partial components of morphology they were positive but widely different (0.08–0.77). With the exception of legs, r G between morphology/gaits and functional traits were positive, with a stronger relationship between morphological traits and performance in WE dressage trial (r G between 0.36 and 0.56) when compared with performance in maneability trial or classical dressage. Height at withers had a r G of 0.40 with performance in classical dressage, but lower r G (0.06 and −0.10) with WE trials. Final score and overall impression had moderate to strong genetic relationships with functional traits, especially with WE dressage trial, while gaits had a strong r G with performance in all the disciplines (0.60–0.72). Indirect selection for morphology/gaits to improve functionality was assessed, by selecting for final score or a combined index of partial scores. Compared to direct selection for functionality, selection for final score or an index combining partial morphological scores would be less effective, resulting in accuracies of, respectively, 0.28 and 0.37 for WE dressage trial, 0.14 and 0.38 for WE maneability trial and 0.22 and 0.39 for classical dressage. Thus, an index combining all partial morphological scores would be better than selection for overall final score, but its relative efficiency compared to direct selection would be about 0.7 in WE dressage trial and classical dressage, and 0.9 in WE maneability trial. Lusitano horses maintain considerable levels of genetic variability, and selection for both morphology and functionality should be effective. The favorable genetic relationships existing between morphology and performance indicate that morphology/gaits traits can play an important role in a two-stage selection program, contributing to enhance selection response when the genetic improvement of working equitation or classical dressage is intended.


      PubDate: 2014-04-27T22:53:02Z
       
 
 
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