for Journals by Title or ISSN
for Articles by Keywords
help

Publisher: Elsevier   (Total: 2970 journals)

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

The end of the list has been reached or no journals were found for your choice.
Journal Cover Livestock Science
  [SJR: 0.715]   [H-I: 69]   [4 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1871-1413
   Published by Elsevier Homepage  [2970 journals]
  • Growth and reproduction genomic-polygenic and polygenic parameters and
           prediction trends as Brahman fraction increases in an Angus-Brahman
           multibreed population
    • Abstract: Publication date: Available online 16 June 2016
      Source:Livestock Science
      Author(s): M.A. Elzo, R. Mateescu, M.G. Thomas, D.D. Johnson, C.A. Martinez, D.O. Rae, J.G. Wasdin, M.D. Driver, J.D. Driver
      The objectives of this research were to estimate genomic-polygenic and polygenic parameters and to evaluate prediction trends as Brahman fraction increased from 0% to 100% in a subtropical multibreed Angus-Brahman (MAB) population for four growth and reproduction traits using single-step genomic-polygenic (GPM) and polygenic models (PM). Traits were 365-d yearling weight (YW), yearling reproductive tract score (RTS), age at first calving (AFC), and first calving interval (FCI). Numbers of phenotypic records were 1,758 for YW, 381 for RTS, 1,385 for AFC, and 985 for FCI. The pedigree file had 6,869 calves, sires, and dams, and genotype file contained 115,711 actual and imputed GGPHD150k SNP markers from 1,547 animals. The 4-trait GPM and PM included contemporary group, age of dam (YW only), sex of calf (YW only), direct heterosis, maternal heterosis (YW only) as fixed effects, and animal and residual as random effects. Genetic parameters were estimated using REML procedures and computed using AIREMLF90. Heritabilities were slightly higher for GPM than PM (0.47 vs. 0.45 for YW, 0.31 vs. 0.30 for RTS, 0.14 vs. 0.12 for AFC, and 0.31 vs. 0.29 for FCI). Genetic correlations were positive between YW and RTS (GPM: 0.55; PM: 0.60), negative between RTS and AFC (GPM: −0.22; PM: −0.55) and between AFC and FCI (GPM: −0.68; PM: −0.67), and near zero for all other trait pairs. The similarity between GPM and PM heritabilities and genetic correlations indicated that the 115,711 GGPHD150k SNP markers added little additional information to that contained in the pedigree. Regression coefficients of breed group EBV means on Brahman fraction were negative (P = 0.0005) for YW, RTS, and FCI, and positive (P < 0.0001) for AFC as Brahman fraction increased. This indicated that heifers with higher Brahman percentages tended to be lighter and less mature as yearlings, older at first calving, and have shorter FCI than heifers with higher Angus percentages under the subtropical environmental conditions of the MAB population. Regression coefficients of individual animal EBV on Brahman fraction showed similar trends, although absolute values were smaller. However, there was a high degree of variation in EBV values within breed groups. Consequently, animals with high, medium, and low EBV existed across all Brahman percentages, thus allowing the selection of replacement animals of all Brahman percentages based on a common set of objectives.


      PubDate: 2016-06-21T09:15:12Z
       
  • Genetic trend estimates for milk yield production and fertility traits of
           the Girolando cattle in Brazil
    • Abstract: Publication date: Available online 14 June 2016
      Source:Livestock Science
      Author(s): Ali William Canaza-Cayo, Jaime Araújo Cobuci, Paulo Sávio Lopes, Robledo de Almeida Torres, Marta Fonseca Martins, Darlene dos Santos Daltro, Marcos Vinicius Gualberto Barbosa da Silva
      Annual genetic trends and selection differentials for 305-d milk yield (305MY), age at first calving (AFC), and first calving interval (FCI) were estimated by four selection paths [sires of bulls (SB), dams of bulls (DB), sires of cows (SC), and dams of cows (DC)] for Girolando dairy cattle in Brazil. A total of 12,739 lactation records were obtained from the Brazilian Girolando Breeders Association with cows calving in the period from 2000 to 2011. Two periods were involved: the first, from 1979 to 1996, corresponding to the formation and expansion of the herd, and second, from 1997 to 2007, characterized by the implementation of the breeding program of the Girolando breed. The whole period from 1979 to 2007 was also considered. The Wombat program was used to fit an animal model for the analyses. Estimated breeding values were extracted to calculate genetic trends for the four selection paths. Greater significant estimates of annual genetic changes for 305MY were obtained for the SC and SB paths, being both during the second period. The greatest annual genetic change estimates for 305MY were 43.06 and 101.97 milk/yr for SC and DB, respectively, during the second period. A favorable genetic response was found for the SB and SC paths for AFC, averaging −4.24 (second period) and −0.32day/year, respectively. For FCI, this effect was from 0.04 to 0.18 range for all paths. When all selection paths were combined, estimated annual genetic changes for 305MY and AFC were 7.40 milk/yr and −0.13day/yr. Therefore, the results of this study showed that a well-designed genetic program has a positive impact on 305MY and AFC and a little or without impact on FCI in Girolando cattle over a 28-yr period.


      PubDate: 2016-06-16T18:02:56Z
       
  • Association of conformation and riding ability in Icelandic horses
    • Abstract: Publication date: July 2016
      Source:Livestock Science, Volume 189
      Author(s): Thorvaldur Kristjansson, Sigridur Bjornsdottir, Elsa Albertsdóttir, Agust Sigurdsson, P. Pourcelot, N. Crevier-Denoix, Thorvaldur Arnason
      The official breeding goal for the Icelandic horse promotes five-gaited horses with a functional and aesthetic conformation. The objectives of the present study were to assess the phenotypic and genetic relationship between standard conformational measurements and scores for riding ability. Further, to investigate if more detailed (3-D) morphometric measurements could discriminate between high-class and low-class horses based on scores for each gait. The data comprised records from standard conformational measurements and scores for the different gaits and the total score for riding ability of all assessed breeding horses in Iceland in 2000–2013 (10,091 horses). Further, records from a subpopulation of 98 haphazardly selected breeding horses that were subject to detailed quantification of the conformation in 3-D and genotyped with respect to DMRT3 genotype, were included in the study. Most of the standard measurements had a significant and curvilinear relationship with the studied riding ability traits. They had generally high estimated heritability but weak or moderate genetic correlation with the total score of riding ability. Proportions in the top line of the horse describing the height of the horse at front compared to hind were found to be most important for the riding ability, revealing the advantage of an uphill conformation. Their estimated heritability and genetic correlation with total score for riding ability designate them as important indicators for performance. Certain lengths, proportions and angles between bones in the fore- and hind limbs also had a significant effect on scores for some gaits. These results can improve the assessment of the conformation and consequently the riding ability of the Icelandic horse.


      PubDate: 2016-06-16T18:02:56Z
       
  • Growth rates of Romane ewe lambs and correlated effects of being mated as
           hoggets or two-tooth ewes on first offspring performance
    • Abstract: Publication date: July 2016
      Source:Livestock Science, Volume 189
      Author(s): E. González-García, D. Hazard
      Growth rates, from birth to first lambing, were characterized for a representative population of Romane ewe lambs belonging to a flock reared in rangelands (south of France). Data from 1359 females born during the decade 2002–2012 were extracted from the INRA genetic national database (GEEDOC), organized and processed using several procedures of SAS (9.3). The effects of year of birth of these females, birth rank (litter size at birth: singletons, SING vs. multiple, TWIN), dam parity (primiparous, PRIM vs. multiparous, MULT) and first order interactions were considered. The growth curves were built. Carry-over effects on their first offspring performance were evaluated with two contrasted first mating systems [as hoggets, Early (n=762), 7 months of age or as two-tooth ewe, Late (n=597), 19 months of age]. Significant interactions of dam parity×birth rank were found for most of body weight (BW) comparisons from birth to first lambing. The MULT×SING and PRIM×TWIN individuals showed the highest and lowest growths, respectively. Being mated as hogget was the consequence of having higher BW at birth, weaning and early mating. However, even if Late mating constituted a change on the reproductive management policy of the farm (since 2010), present results showed that two-tooth ewes mostly corresponded to lighter ewes, thus having a weaker growth performance from birth to the early mating age. Average litter size at first lambing (1.8±0.01 vs. 2.1±0.01 lambs/lambing), litter weight (6.2±0.03 vs. 7.4±0.02kg), multiple-born lambs (70.4 vs. 79.3%), number of lambs weaned (1.02±0.006 vs. 1.55±0.004) and total lamb weaned production (23.2±0.12 vs. 31.3±0.08kg of weaned lambs) were lower (P<0.0001) in hoggets when compared to two-tooth ewes (39.7±0.07 vs. 50.6±0.04kg BW at first mating, respectively). The gender ratio of the first offspring was not affected by the age at first mating (female to male ratio: 49:51).


      PubDate: 2016-06-16T18:02:56Z
       
  • APPLICATION OF GENOMIC DATA TO ASSIST A COMMUNITY-BASED BREEDING PROGRAM:
           A PRELIMINARY STUDY OF COAT COLOR GENETICS IN MORADA NOVA SHEEP
    • Abstract: Publication date: Available online 14 June 2016
      Source:Livestock Science
      Author(s): Maria Malane Magalhães Muniz, Alexandre Rodrigues Caetano, Concepta McManus, Lillian Cristina Gomes Cavalcanti, Débora Andrea Evangelista Façanha, Jacinara Hody Gurgel Morais Leite, Olivardo Facó, Samuel Rezende Paiva
      The Brazilian Sheep Breeders´ Association recognizes two varieties of the Morada Nova hair breed, white and red. However, the black variety and / or animals with a pigmented nose has frequently been disqualified from genealogical records. Previous studies suggest that this genetic group might be similar to the red variety. Thus, the aim of this study was to conduct a Genome-wide association study (GWAS) to identify genomic regions related to hair color and confirm the position of black relative to other Morada Nova varieties. After quality controls, 48 animals were genotyped for 45.982 SNPs using the OvineSNP50k BeadChip. Estimated Fst values between white and red animals, white and black, and red and black were 10.78% (p<0.00001), 9.23% (p<0.00001), and 2.93% (p<0.00001), respectively. The comparison between white and red (n=30) versus black (n= 18) animals revealed 10 highly significant SNPs, most located in a 6.8Mb window in Oar14 which contains the MC1R gene. Differences between black and red coats are the result of the expression of different alleles of the same gene without directly affecting productive/reproductive characteristics. These two varieties showed low genetic variation, insufficient to define them as different groups, and to increase the breeding herd, the animals with black hair and/or pigmentation of the nose should be used breeding purposes. The results of this study contribute to the discussion of the importance in reconciling conservation, traditional breed standards and breeding of farm animals.


      PubDate: 2016-06-16T18:02:56Z
       
  • Excess of dietary benzoic acid supplementation leads to growth
           retardation, hematological abnormality and organ injury of piglets
    • Abstract: Publication date: Available online 15 June 2016
      Source:Livestock Science
      Author(s): Yan Shu, Bing Yu, Jun He, Jie Yu, Ping Zheng, Zhengcai Yuan, Daiwen Chen, Xiangbing Mao
      Benzoic acid has been widely used in feed industry as an organic acidifier and preservative. However, it is unknown whether excessive benzoic acid in diets would have a potential risk on pigs. This study was conducted to investigate the safety of benzoic acid that was used in diets of piglets. A total of 120 weaned pigs [(Yorkshire × Landrace) × Duroc] with initial average BW of 8.16 ± 0.09kg (28 ± 1 d of age) were randomly allotted to four groups receiving diets supplementing 0%, 0.5%, 2.5% and 5.0% benzoic acid for 56 d. Supplementing 0.5% benzoic acid in the diet had no negative effects on the growth of piglets, and increased antioxidant enzyme (CAT and GSH-Px) activities in the liver (P < 0.05). Dietary 2.5% benzoic acid supplementation decreased ADFI and ADG of pigs from 1 to 28 d (P < 0.05), reduced the white blood cell and globulin on d 56 (P < 0.05), and resulted in spleen injury on d 28 and d 56. In addition, besides impairing growth performance of pigs during the whole experiment (P < 0.05), supplementing 5.0% benzoic acid in the diet increased the relative liver weight on d 56 (P < 0.05), enhanced the serum alanine aminotransferase and aspartate aminotransferase of pigs on d 28 (P < 0.05), and led to liver injury. Moreover, dietary 5.0% benzoic acid supplementation also decreased the red cell pressure product, red blood cell volume and increased red cell distribution width-SD/CV on d 28 (P < 0.05), and resulted in the serious spleen damage. When compared with pigs fed by the diet supplemented 0.5% benzoic acid, pigs fed the diets containing 2.5% or 5.0% benzoic acid would have higher benzoic acid residues in the liver and kidneys on d 28 and d 56 (P < 0.05). These results suggested that dietary 0.5% benzoic acid supplementation had the beneficial effects on piglets, but supplementing excessive (2.5% and 5.0%) benzoic acid in the diets could lead to growth retardation, hematological abnormality and the injury of some organs (liver and spleen).


      PubDate: 2016-06-16T18:02:56Z
       
  • Editorial Board
    • Abstract: Publication date: July 2016
      Source:Livestock Science, Volume 189




      PubDate: 2016-06-16T18:02:56Z
       
  • Comparative assessment of development competence of zona-intact and
           zona-free cloned goat embryos produced by innovative micromanipulation
           tools
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): Dharmendra Kumar, Bikash Chandra Sarkhel
      The present study demonstrated a new approach for production of zona free cloned embryos in goat wherein, instead of hand guided bisection applied under Hand-made cloning technique, we have adopted micromanipulator based enucleation using innovative microtools viz., Bisection blade and Aspiration pipette. Using bisection blade, oocyte was bisected into two halves and one half having polar body-MII chromosome was instantly discarded by aspiration pipette, resulted into 100% enucleation efficiency. This process did not require Hoechst staining for confirmation of enucleation. The electrofusion process was carried out using indigenously prepared electrodes for individual electrofusion of demicytoplasts-somatic cell triplet, which revealed significantly higher (P≤0.01) fusion rate (92.78±0.5%) as compared to conventional technique (64.61±0.93%) for zona intact embryos. The developmental rates of zona-free embryos were observed as significantly higher (P≤0.01) 2–4 cells (79.13±0.82 vs 29.42±0.55), 8–16 cells (66.68±01.02 vs 23.83±0.9), morula (31.93±1.12 vs 17.93±1.07), blastocysts (24.0±1.56 vs 7.79±0.98) and mean blastomere counts (210.3±2.3 vs 154.0±1.60) as compared to zona-intact embryos.


      PubDate: 2016-06-16T18:02:56Z
       
  • The effects of male and female immunocastration on growth performances and
           carcass and meat quality of pigs intended for dry-cured ham production: A
           preliminary study
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): A. Daza, M.A. Latorre, A. Olivares, C.J. López Bote
      A total of 48 Duroc×(Landrace×Large White) pigs, 24 males and 24 females, with 85±3 d of age were used to study the effect of sex and immunocastration on growth performances and carcass and pork quality. There were 4 experimental treatments; surgical castrated males (SCM), immunocastrated males (ICM), entire females (EF) and immunocastrated females (ICF). The surgical castration had been carried out in 12 males when were 5±3 d of age. The immunocastration consisted in two vaccinations with Improvac®, in 12 boars and in 12 gilts, at the beginning of the trial and 28 d later (45.4 and 70.6kg body weight as average, respectively). Pigs were intended for dry-cured ham elaboration; therefore, heavy body weight (126kg and 167 d of age as average) and a minimum of carcass fat depth (20mm) were required. During the overall period (from days 0–82), SCM were less efficient converting feed into gain than the rest of the treatments (P=0.049). At slaughter, ICM were heavier than SCM and ICF with EF being intermediate (P=0.05) and ICF were fatter, as much at 10th rib (P=0.05) as at level of Gluteus medius muscle (P=0.043), than EF with males (SCM and ICM) in an intermediate position. As a consequence, EF had the leanest carcasses (P=0.048) and 25% of them were rejected for lack of fatness vs 0% in the other treatments (P=0.02). Pork from ICF was redder (higher a*) than that from ICM (P<0.001) and meat from SCM showed a more intense color (higher C*) (P=0.03) and tended to have lower level of oxymyoglobin (P=0.061) and metmyoglobin (P=0.082) than that from EF. The intramuscular fat content was not affected. The inmunocastration of males or females had limited influence on major fatty acids of subcutaneous or intramuscular fat. It can be concluded that immunocastration could be interesting in pigs intended for dry-cured ham elaboration because in males improved the feed conversion ratio with no penalization of carcass or meat quality, in comparison to surgical castration, and in gilts increased backfat thickness of carcass reducing to 0% the rejections at slaughterhouse for lack of fatness.


      PubDate: 2016-06-16T18:02:56Z
       
  • Effects of L-glutamine on growth performance, antioxidant ability,
           immunity and expression of genes related to intestinal health in weanling
           pigs
    • Abstract: Publication date: July 2016
      Source:Livestock Science, Volume 189
      Author(s): J. He, G.D. Feng, X. Ao, Y.F. Li, H.X. Qian, J.B. Liu, G.Y. Bai, Z.Z. He
      Although there were many reports about the L-glutamine (Gln) on growth performance and intestine health, little studies were conducted to determine the effects of Gln on nutrient digestibility and expression of genes related to intestinal health. Besides, the glutamic acid with lower price was assumed to substitute the glutamine partly, which can partly be synthesized by the glutamic acid. Therefore, this study was conducted to determine the effects of Gln on growth performance, apparent total tract digestibility (ATTD), blood profiles, related enzyme activity, small intestinal mucosal morphology and expression of genes related to intestinal health in weanling pigs. A total of 250 [(Landrace× Yorkshire)× Duroc] pigs (9.22±0.11kg) were blocked on the basis of sex and body weight, and then randomly assigned to 1 of the following 5 treatments: 1) CON (basal diet); 2) 1/9 Gln/Glu (CON +0.1% Gln +0.9% Glu); 3) 2/8 Gln/Glu (CON +0.2% Gln +0.8% Glu); 4) 1% Gln (CON +1% Gln); 5) 1% Glu (CON +1% Glu). There were 5 replications (pens) per treatment and 10 pigs per pen in this 28-d experiment. Pigs fed the 1% Gln diet had a higher ADG and G: F (P<0.05) than those fed CON diet during d 0–14 and the overall period. The ATTD of dry matter (DM) and nitrogen (N) was the greatest (P<0.05) in response to the 1% Gln diet on d 28. Compared with CON, feeding the 1% Gln diet increased (P<0.05) the content of superoxide dismutase (SOD), while it decreased (P<0.05) the malondialdehyde (MDA) content on d 28 in the serum. The levels of immunoglobulin G (IgG) and immunoglobulin M (IgM) in the serum was increased in the 1% Gln group (P<0.05), whereas the percentage of the cluster of differentiation 8 receptors (CD8+) was reduced (P<0.05) in the 1% Gln group compared with CON. The activity of lactase was improved (P<0.05) in pigs fed the 1% Gln diet compared with those fed CON diet. However, the activity of glutamine synthetase (GS) was reduced (P<0.05) in pigs fed Gln1, Gln2, the 1% Gln and 1% Glu diets compared with those fed CON diet. Feeding of the 1% Gln diet declined (P<0.05) the relative expression levels of peroxisome proliferator-activated receptor γ (PPARγ) and mammalian target of rapamycin (mTOR), while improving (P<0.05) the relative expression level of pyruvate kinase (PK) in the duodenum, jejunum and ileum, respectively, compared with CON. Taken together, the 1% Gln supplementation to weanling pig diets could modify intestinal health and improve ATTD of nutrients so as to benefit the growth performance. Nevertheless, the Gln/Glu use could not achieve the effects of 1% Gln group in this study.


      PubDate: 2016-06-16T18:02:56Z
       
  • Relationship of pulmonary arterial pressure and terrain use of Angus cows
           grazing high-altitude foothill rangelands
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): Derek W. Bailey, Milton G. Thomas, Tim N. Holt, Mitch B. Stephenson, R. Mark Enns, Scott E. Speidel
      Pulmonary arterial pressure (PAP) score is used as an indicator trait for risk of hypoxia-induced pulmonary hypertension, which is commonly termed high altitude disease and observed in cattle grazing at altitude ≥1500m. We hypothesized that cows with higher PAP score would avoid using high elevations, steep slopes and areas far from water while grazing foothill rangeland. During 2013 and 2014, forty-one mature Angus cows from a breeding population of cattle selected for tolerance to high altitude were tracked with global positioning system (GPS) collars for 27 and 17 days, respectively. These cows grazed a 1210 ha foothill rangeland pasture with a vertical relief of 2150–2411m. Pulmonary arterial pressure was measured for each animal at 1 year of age (yearling PAP; 38.2mmHg±5.1SDmmHg) and before tracking (mature PAP; 42.6mmHg±3.7SD). Yearling PAP score was not correlated with the mature PAP score (r=0.23, P=0.15). Terrain use varied among individual tracked cows, and the range among cows within the same pasture was 59m (2204m±15SD) for average elevation use, 4.7% points (8.9%±0.2SD) for average slope use and 247m (446m±77SD) for average distance from water. No correlation was detected between mature PAP scores and terrain use metrics (mean elevation, slope and distance from water of tracked locations; r=−0.16, 0.24, 0.25; P>0.10). Similarly, no correlation was detected (P>0.10) between yearling PAP score and terrain use metrics. Yearling and mature PAP scores were not correlated (P>0.50) to indices of terrain use that combined elevation and slope use (rough index) and elevation, slope and distance from water (rolling index). Yearling PAP and mature PAP were not useful predictors (P>0.10) of terrain use in multiple regression analyses. Angus cows in this study were apparently adapted to high elevations and PAP score had little, if any, relationship with their metrics of grazing distribution of foothill rangeland. In situations where elevation was higher, terrain was more rugged or cattle were not adapted, results may differ from those observed in this study.


      PubDate: 2016-06-16T18:02:56Z
       
  • Editorial Board
    • Abstract: Publication date: June 2016
      Source:Livestock Science, Volume 188




      PubDate: 2016-06-16T18:02:56Z
       
  • Sand bedded freestall and compost bedded pack effects on cow hygiene,
           locomotion, and mastitis indicators
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): E.A. Eckelkamp, J.L. Taraba, K.A. Akers, R.J. Harmon, J.M. Bewley
      The objective of this study was to assess differences between compost bedded pack (CBP) and sand freestall barns (SFB) for mastitis indicators (herd clinical mastitis, SCC, high SCC prevalence (% of herd ≥200,000cells/mL SCC), and BTSCC), and locomotion, hygiene, and hock scores. This study was conducted on commercial Kentucky dairy farms using CBP (n=8) or SFB (n=7) as the primary lactating cow housing facility from May 2013 to May 2014. To indicate good management practices, eligible herds had to maintain a yearly mean SCC <300,000 the year before enrollment in the study. Milk samples were collected from quarters that presented clinical signs of mastitis as identified by milking personnel. Each herd was visited biweekly (n=26 visits) over the study period. Each visit included evaluating 50 cows per herd for hygiene, locomotion, and hock scores. Somatic cell count (SCC) and high SCC prevalence (percentage of animals in each herd with a test day SCC ≥200,000cells/mL) were collected from Dairy Herd Information Association (DHI, Raleigh, NC). Bulk tank SCC from each pick up was gathered from each dairy's milk purchaser. Bulk tank SCC from each pick up for all Kentucky herds on DHI regardless of SCC or housing type from January 2013–2014 was requested from the Kentucky Milk Quality Safety Branch to determine differences among all bedding types without selecting for herds enrolled in DHI. Overall, no differences between 8 CBP and 7 SFB selected based on SCC existed for herd locomotion, hygiene, or hock health. No differences were observed for the main effects of housing, maximum temperature humidity index, or hygiene score on SCC, high SCC prevalence, clinical mastitis incidence, or bulk tank SCC for 8 CBP and 7 SFB Kentucky herds. Similarly, for Kentucky DHI herds, bulk tank SCC was not different among herds using CBP, freestall barns, and tie-stall barns. Herds using CBP alongside freestall barns had the lowest bulk tank SCC in Kentucky. These results indicate that, when managed properly, CBP can provide a housing environment comparable to SFB. Freestalls, tie-stalls, and compost bedded pack barns for all herds on DHI had similar bulk tank SCC.


      PubDate: 2016-06-16T18:02:56Z
       
  • Environmental impact of a cereal-based intensive beef fattening system
           according to a partial Life Cycle Assessment approach
    • Abstract: Publication date: Available online 13 June 2016
      Source:Livestock Science
      Author(s): Marco Berton, Giacomo Cesaro, Luigi Gallo, Giacomo Pirlo, Maurizio Ramanzin, Franco Tagliapietra, Enrico Sturaro
      This study investigated the environmental impact of the intensive beef fattening sector in North-Eastern Italy. A partial Life Cycle Assessment method was used with the boundaries of the system set from the arrival of stock calves, mainly born and raised in French suckler cow-calf systems, to the sale of finished young bulls and heifers to the slaughterhouses. One kg of body weight gained (BWG) was taken as the functional unit. This study examined 327 batches (groups of animals homogeneous for sex, genotype, origin, fattening farm and finishing period, 63±32 heads of average size) fattened by 16 farms. Data on animal performance were recorded for each batch. Diet composition and feed intake were collected for each beef category (combination of genotype and sex) within farms. On- and off-farm feed production data and materials used were recorded for each farm. Impact categories regarded (mean values and standard deviation per kg BWG are provided between brackets): global warming potential (8.4 ± 1.6 kg CO2-eq), acidification potential (197 ± 32 g SO2-eq), eutrophication potential (65 ± 12 g PO4-eq), cumulative energy demand (62 ± 16 MJ), and land occupation (8.9 ± 1.7 m2/year). The contribution to global warming, acidification, and eutrophication potentials was greater for the on-farm than off-farm activities, whereas the opposite pattern was found for cumulative energy demand and land occupation. When referred to the whole production system, adding the global warming potential of French suckler cow-calf systems taken from the literature to those found in the present study for the fattening period, the resulting GHG emission was comparable to those reported for other suckler cow-based beef chain systems. The impact category values obtained for each batch were analysed with a linear mixed model which included the effects of farm (random effect), beef category, season of arrival in the fattening farm, and body weight class at the start of the fattening period within beef category. Beef category greatly affected all impact categories and variation across farms was notable. In conclusion, the beef fattening system taken into account was characterized by an overall global warming potential similar to, or slightly lower than, those reported for other beef systems, due to its productive efficiency, but showed a high energy demand, due to the relevance of off-farm activities. Different impact categories evidenced notable variation among farms, suggesting that there is potential for decreasing impacts through appropriate and specific management procedures of herds and farms.


      PubDate: 2016-06-16T18:02:56Z
       
  • Understanding compost bedded pack barns: Interactions among environmental
           factors, bedding characteristics, and udder health
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): E.A. Eckelkamp, J.L. Taraba, K.A. Akers, R.J. Harmon, J.M. Bewley
      The objective of this study was to describe relationships among compost bedded pack barn (CBP) measurements (moisture, internal temperature, nutrient content, and bedding bacterial counts), ambient weather conditions, and udder health. Data was collected every 2-weeks (n=25 visits) from 8 Kentucky dairy farms with CBP from May 2013 to May 2014. A single observer scored 50 cows per farm for hygiene and collected compost internal temperature, moisture, and compost samples from 9 evenly distributed areas in each barn. Weighted average somatic cell count (SCC), high SCC prevalence (HSP), and reported clinical mastitis incidence (RCMI) were collected from herd records and milking personnel. Compost internal temperature increased with increasing maximum barn temperature (BT). Compost moisture content decreased with increasing BT. Herd hygiene score decreased with increasing BT and increased with increasing compost moisture content. Herd SCC and HSP both increased with increasing BT but were unaffected by compost measurements. As compost internal temperature increased, staphylococci, streptococci, and bacilli species growth in the pack area decreased and coliform species growth increased. Low CBP moisture and high CBP temperature reduced bacteria levels. Cow hygiene and udder health indicators had a stronger relationship with BT than with CBP internal temperature and moisture.


      PubDate: 2016-06-16T18:02:56Z
       
  • Influence of four commercial porcine circovirus type 2 (PCV2) vaccines on
           the improvement of production parameters in pigs with maternally derived
           antibodies
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): Abel Villa-Mancera, Karina Hernández-Guzmán, Jaime Olivares-Pérez, Pedro Molina-Mendoza
      Anti-PCV2 antibodies in serum, viremia and production parameters (average daily weight gain [ADWG] and mortality) were assessed in piglets immunized with four commercial PCV2 vaccines in the presence of high levels of maternally derived antibodies (MDA). A total of 217 sows were vaccinated (V) at 7 and 4 weeks before farrowing with an inactivated PCV2 vaccine. All piglets derived from these sows (n=2215) were divided into five groups and 3-week-old piglets were injected with one of four different vaccines (A-D): V sows-VA piglets (n=437), V sows-VB piglets (n=424), V sows-VC piglets (n=432) and V sows-VD piglets (n=417). A control group of non-vaccinated piglets (V-NV, n=426) received phosphate-buffered saline (PBS). Sows (n=39) received PBS (non-vaccinated group). The ADWG of vaccinated piglets (V-VA, V-VB, V-VC and V-VD) ranging from 661 to 669g/day were significantly higher than the control group (V-NV, 630g/day), but differences in ADWG between vaccinated groups were not statistically significant. An overall mortality ranging from 7.23% to 9.20% was observed in vaccinated piglets (V-VA, V-VB, V-VC and V-VD) compared with the control group (V-NV, 20.02%). The number of genomic copies of PCV2 in serum for the control group were significantly higher than those of the four vaccinated groups at 10, 15, and 22 weeks of age. Vaccination increased serum antibodies in sows 3- to 4-fold; PCV2-specific antibody titers in sera from piglets were very similar to those of their sows. The antibody titers in vaccinated piglets and V-NV group decreased gradually about 3-fold until the week 10. In the presence of high MDA levels, piglets immunized with four commercial PCV2 vaccines showed a significantly reduction of PCV2 infected pigs, viral load, number of PCV2-sero positive pigs and mortality rate as well as significantly higher ADWG than those of the V-NV group.


      PubDate: 2016-06-16T18:02:56Z
       
  • A comparison of microbial profiles of different regions of the equine
           hindgut
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): K. Fliegerova, E. Mura, J. Mrázek, G. Moniello
      The microbial profiles of the luminal content of five hindgut segments of one healthy horse were compared with rectal sample to elucidate the effect of anatomical region on bacterial and archaeal community structure and to evaluate the use of faeces as a representative model of large intestine. The qualitative and quantitative changes of the microbial community composition of caecum, right ventral colon, left ventral colon, left dorsal colon, right dorsal colon and faeces were monitored by denaturing gradient gel electrophoresis (DGGE) and real-time PCR using universal primers amplifying the V3 region of 16S rDNA. DGGE fingerprints revealed extensive bacterial as well as archaeal diversity in all studied samples and reflected shifts in the community structure among the caecum, the different segments of the colon and the faeces. Archaeal DGGE pattern of the caecum differed from all the other parts of the hindgut. Microbial profile similarities were found between the left and the right dorsal colon and between the left ventral colon and the faeces. The excised DGGE bands were related to uncultured bacteria and methanogens, the dominant archaeal bands of caecum and faeces were related to Methanocorpusculum sp. Diversity indices indicated the higher diversity for bacteria than for archaea and the dominance of some methanogenic species. The real-time PCR revealed the differences in the microbial quantitative composition of each segment, showing the highest number of total bacteria and archaea in the right ventral colon. The analyses of bacterial and archaeal composition along the one equine hindgut indicate that the faecal sample is similar to that of the left ventral colon, but does not represent the microbial community of the caecum and other parts of the colon.
      Graphical abstract image

      PubDate: 2016-06-16T18:02:56Z
       
  • Milk production and milk fatty acids in dairy cows fed crushed rapeseed or
           rapeseed oil
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): A. Hoffmann, S. Görlich, H. Steingass, H. Terry, M. Schollenberger, K. Hartung, R. Mosenthin
      The effect of crushed full fat rapeseed or its free oil on milk yield and milk fatty acid composition was assed using three groups of mid-lactating Holstein dairy cows, assigned to a randomized 3×3 Latin square design. Dietary treatments included a control (CTL, ether extract 2.3% of dry matter, DM) and two experimental treatments (ether extract 4.2% of DM) supplemented with the same amount of fat either supplied as 4.9% of DM crushed full fat rapeseed, RCor2.2% of DM free rapeseed oil RO. Both experimental treatments increased DM intake (P<0.005) and daily milk yield (P<0.001). Milk fat and protein concentration was decreased in the supplemented diets (p<0.001). A reduced (p<0.001) yield of saturated fatty acids (FA) and an increased yield of long chain and unsaturated FA (p<0.001 for mono unsaturated FA and p<0.05 for poly unsaturated FA) in milk fat was observed for both experimental treatments. The results confirmed a reduced de novo synthesis and an increased carry-over of dietary FA upon feeding dairy cow diets supplemented with long chain and unsaturated FA. The lower degree of saturation in milk fat from cows fed RC compared to RO indicates a partial protection of the crushed rapeseed against ruminal hydrogenation.


      PubDate: 2016-06-16T18:02:56Z
       
  • Rumen microbial protein flow and plasma amino acid concentrations in early
           lactation multiparity Holstein cows fed commercial rations, and some
           relationships with dietary nutrients
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): N. Swanepoel, P.H. Robinson, L.J. Erasmus
      Common contemporary diet formulation methods involve factorial or empirical models which simulate ruminal fermentation and post ruminal absorption to predict nutrient supply and needs. However, due to their inability to encompass all animal factors that affect digestion and absorption, metabolic models inadequately predict microbial protein (MCP) synthesis in the rumen and passage of nutrients such as protein and amino acids (AA) to the small intestine. Practical and simple on-farm methods to obtain “real time” values directly from cows are required to establish normal ranges of MCP flow from the rumen and plasma AA concentrations on commercial dairy farms. Urine purine derivative (PD) output, an index of MCP supply to the intestine when analyzed in spot urine samples, can accurately predict MCP flow from the rumen under farm conditions. Blood sampling from the tail vein is easily performed on commercial dairy farms and concentrations of free AA in these plasma samples, representative of intestinally absorbed AA, can be used as an index to predict limiting AA. A group of 20 commercial dairy farms, milking 2677±372 cows either 2 or 3 times a day were selected and one of their early lactation pens holding 255±20 cows were used to represent the range of nutritional strategies and rations fed to California dairy cows. On the day of sampling, one load of early lactation total mixed ration (TMR) was sampled and 20 pre-selected cows were body condition scored (BCS). Directly after scoring, the 4 cows with the highest, and the 4 cows with the lowest BCS values were removed to collect 12 tail vein blood samples from the group with average BCS scores. Spot urine samples were collected from all voluntarily urinating cows (retaining 6–12 samples/pen to match the characteristics of the cows pre-selected for BCS scoring and blood sampling). Most rations contained alfalfa hay, corn silage, almond hulls, corn dried distillers grains, corn grain, cottonseed, canola meal (solvent) and a mineral premix. Selected cow groups produced 45±1.2kg milk/day at 73±0.5 days in milk with a BCS of 2.6±0.04 at 2.8 lactations. There were no correlations between MCP and milk production, but MCP flow from the rumen was correlated to organic matter and neutral detergent fiber content of the TMR (P<0.01 and P=0.03 respectively). Plasma AA concentrations were correlated with rumen undegradable crude protein (CP) and starch content of the TMR, with many inter-correlations among AA, but no plasma AA concentration was correlated to milk production. Results show that 8 urine samples and 6 blood samples/group provided accurate representation of the group. This study documents ranges of MCP flowing from the rumen (1703±54.6g CP/day), and plasma AA levels (with low variation within AA), in early lactation multiparity Holstein cows fed a range of contemporary dairy rations with multiple ingredient profile combinations. Since farms selected were well managed operations with cow groups selected to represent averages in early lactation, this data can be used as a benchmark for high, low and mean levels of MCP flow, and plasma AA concentrations, as well as provide real time evaluation of rations to identify possible rumen microbial growth and/or absorbable AA issues in commercial dairy cows.


      PubDate: 2016-06-16T18:02:56Z
       
  • Estimation of linkage disequilibrium levels and haplotype block structure
           in Chinese Simmental and Wagyu beef cattle using high-density genotypes
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): Hong Niu, Bo Zhu, Peng Guo, Wengang Zhang, Jinglong Xue, Yan Chen, Lupei Zhang, Huijiang Gao, Xue Gao, Lingyang Xu, Junya Li
      With the advance of high-throughput genotyping technologies, it is possible to estimate the pattern of linkage disequilibrium (LD) and haplotype block structure at genome wide level in farm animals. Understanding LD characteristics and haplotype blocks can provide useful information to guide genome wide association study (GWAS) and genomic selection (GS). In this study, we investigated the LD pattern and haplotype block structure in two beef cattle populations (Chinese Simmental and Wagyu) using the BovineHD BeadChip. We found the average LD measured by r 2 in Chinese Wagyu was higher than that in Simmental. We observed LD decayed more slowly on the X chromosome than autosomes for both populations. The persistence of LD phase varied from 0.96 at a distance of <2.5kb to 0.51 at a distance from 400kb to 500kb. The estimated ancestral effective population sizes (N e ) in Chin e se Simmental and Wagyu 5 years ago were approximately 74 and 23, respectively. Moreover, we detected 50,475 (991.1Mb, 69.3%) haplotype blocks shared by two populations, 18,440 (238.9Mb, 16.7%) unique blocks in Chinese Simmental and 15,417 (199.8Mb, 14%) in Wagyu. Our study revealed that the r 2 dropped below 0.2 at distances of 34kb and 40kb in Chinese Simmental and Wagyu, which indicated that the implementation of GS for both populations require at least 77,941 and 66,250 markers, respectively. The pattern of LD mirrored the slightly different selection histories for Chinese Simmental and Wagyu, and our result suggested the shared haplotype blocks may offer valuable insights for the implementation of genome wide association and genomic selection studies based on multi-population.


      PubDate: 2016-06-16T18:02:56Z
       
  • Optimizing the gain of social genetic effect under the control of
           inbreeding using genetic algorithm
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): Pingxian Wu, Yanzhi Jiang, Li Zhu, Xuewei Li, Guoqing Tang
      Social interactions among animals are widely existed in livestock population. However, some studies showed that the selection of social genetic effect leaded to extra increase of inbreeding. In this study, two optimization methods (SBLUP+GA1, SBLUP+GA2) based on genetic algorithm were used to obtain the optimal genetic contributions of seedstocks and maximize the average genetic gains of direct and social genetic component while minimizing the inbreeding. In SBLUP+GA1, only the contributions of sires were optimized. In SBLUP+GA2, the contributions of sires and dams were optimized together. The results showed SBLUP+GA1 and SBLUP+GA2 resulted in 18.52% and 25.93% lower inbreeding rate than common social genetic effect selection based on BLUP method (SBLUP) under base parameters, respectively. Under that situation, the average gains for direct, social and total genetic effect component in SBLUP+GA1 were actually improved 3.59%, 10.02% and 4.32% relative to SBLUP, respectively. In SBLUP+GA2, they were 1.28%, 10.00% and 2.02%, respectively. SBLUP+GA2 resulted in lower inbreeding rate, but, obtained slightly less genetic gain than SBLUP+GA1.


      PubDate: 2016-06-16T18:02:56Z
       
  • An association analysis between a missense polymorphism at the pig PCSK9
           gene and serum lipid and meat quality traits in Duroc pigs
    • Abstract: Publication date: August 2016
      Source:Livestock Science, Volume 190
      Author(s): Wojciech Chański, Rayner González-Prendes, Anna Castelló, Jordi Jordana, Arianna Manunza, Raquel Quintanilla, Marcel Amills
      A genome-wide association analysis in a Duroc pig population allowed us detecting a genomic region on pig chromosome 6 (141–147Mb) that was associated with serum cholesterol (CHOL), triglyceride (TRIG) and low-density lipoprotein (LDL) concentrations. This region contains the proprotein convertase subtilisin-like kexin type 9 (PCSK9) gene (SSC6, 145Mb), which has a key role in the regulation of CD36, LDL receptor and very low density lipoprotein (VLDL) receptor levels. In the current work, we have genotyped by pyrosequencing a missense PCSK9 c.1222G>A mutation (E408K) in 273 Duroc pigs. The performance of an association analysis with the GEMMA software did not reveal any association between PCSK9 genotype and serum lipid concentrations, evidencing that this polymorphism is not the causal mutation of the CHOL, TRIG, and LDL SSC6 QTL. However, we detected an association, that was highly significant at the nominal level, between PCSK9 genotype and palmitelaidic content at the gluteus medius muscle (P-value = 0.008). There is evidence that PCSK9 induces the degradation of CD36, a key long-chain fatty acid transporter, and that it may decrease the uptake of palmitate. However, the E408K polymorphism analysed in the current work is not predicted to be deleterious, suggesting that the associations found are probably due to the linkage of this polymorphism with a causal mutation yet to be found.


      PubDate: 2016-06-16T18:02:56Z
       
  • Extended lactation in high-yielding Holstein cows: Characterization of
           milk yield and risk factors for lactations &gt;450 days
    • Abstract: Publication date: July 2016
      Source:Livestock Science, Volume 189
      Author(s): M. Mellado, J.M. Flores, A. de Santiago, F.G. Veliz, U. Macías-Cruz, L. Avendaño-Reyes, J.E. García
      Two data files consisting of 3278 (one herd) and 4393 lactations (three herds) were used to characterize milk production of high-yielding Holstein cows milked three times per day and experiencing extended lactations (up to 1399 days) in a hot environment. Additional objectives were to identify risk factors for the occurrence of extended lactations, to assess the association between lactation length and milk yield and to determine the conception rates of cows with extended lactations and with multiple services. Thirty percent of lactations were between 450 and 1399 days. Lactation yield of cows with lactations >900 days was over 30,000kg. Average daily milk yield from 305 to >450 days in milk was 29.9 and 31.9kg for primiparous and multiparous cows, respectively. The epidemiological analysis of risk factors for extended lactations using a multiple variable logistic regression indicated that ketosis (OR=1.4), peak milk yield (<50 vs >50kgd−1, OR=1.4), temperature-humidity index at 60 days postpartum (<82 vs >82 units, OR=1.4), retained placenta (odds ratio (OR)=1.5), 305-d milk yield (<11,000 vs >11,000kg, OR=1.6) and the occurrence of metritis (OR=1.8), significantly increased the risk for lactations >450 days. Primiparous cows had less than half the risk of extended lactations (OR=0.3) compared to multiparous cows. Conception rate in cows with extended lactations decreased as number of services increased (conception rate=50.5% for 4 services and 13% for ≥14 services). The data showed that well-managed Holstein cows milked three times daily were capable of lactating for over 1200 days with remarkably high persistency and with high milk yield at drying-off. Reproductive and metabolic disorders associated with calving were important risk factors for extended lactations.


      PubDate: 2016-05-19T23:03:46Z
       
  • Multiple-trait analysis of a long-term selection experiment for
           non-destructive deformation in White Leghorns: Evolution of genetic
           parameters for traits related to eggshell strength
    • Abstract: Publication date: Available online 14 May 2016
      Source:Livestock Science
      Author(s): Olivier Gervais, Keijiro Nirasawa, Christian E. Vincenot, Yoshitaka Nagamine, Kazuyuki Moriya
      Background Economic losses resulting from poor eggshell quality are critical issue for the poultry industry, challenging researchers to find practical solutions to improve the resistance of eggshells to external pressure. Although many studies have proposed non-destructive methods to improve shell strength, relatively few long-term experiments are documented which use non-destructive deformation as a selection criterion. Using REML under a five-trait animal model, this study evaluates a long-term selection experiment for non-destructive deformation that was conducted on two divergent lines of White Leghorns and provides insight into how the selection process affects other traits related to eggshell strength (breaking strength, shell thickness, shell percentage, and shell weight). The evolution of the genetic parameters over the course of the experiment was analyzed also. Results The heritability estimates for non-destructive deformation were 0.388 (± 0.032) for the strong line and 0.415 (± 0.030) for the weak line. For eggshell breaking strength, heritability values were 0.347 (± 0.028) for the strong line and 0.482 (± 0.032) for the weak line. Strong genetic correlations were found between non-destructive deformation and eggshell breaking strength (–0.774 ± 0.031 and –0.840 ± 0.022 for the strong and weak lines, respectively). Estimated heritabilities for the other traits varied from 0.448 to 0.591 for the strong line and from 0.493 to 0.672 for the weak line. In addition, these traits showed large negative genetic correlations with non-destructive deformation, from –0.623 to –0.903 for the strong line and from –0.730 to –0.934 for the weak line. Moreover, the regression coefficients associated with the generation means of the breeding values revealed an asymmetric response between the two lines, and further analysis of the evolution of the genetic parameters over the course of the experiment hinted at possible reasons for this asymmetry. Conclusions The large genetic correlation between non-destructive deformation and eggshell breaking strength and the similarity of the heritability estimates for these two traits (medium to moderately high), suggest that non-destructive deformation can be used instead of breaking strength as a means to evaluate eggshell strength. Nevertheless, additional research is necessary to better understand the effect of selection for non-destructive deformation on factors not considered in this study, such as egg production and hatching rate.


      PubDate: 2016-05-19T23:03:46Z
       
  • Herbs and spices inclusion as feedstuff or additive in growing rabbit
           diets and as additive in rabbit meat: a review
    • Abstract: Publication date: Available online 18 May 2016
      Source:Livestock Science
      Author(s): A. Dalle Zotte, C. Celia, Zs. Szendrő
      The European ban on the non-therapeutic use of antibiotic growth promoters and limits on the use of other drugs have increased digestive disorders and mortality in growing rabbits. In addition, consumers demand natural products, and therefore synthetic active compounds should be replaced by natural ones. This has increased the search for alternatives, such as herbs, spices and their extracts (botanicals) as replacers. Plants (whole plants, leaves or seeds, mainly used as feedstuffs) and their extracts (considered as additives) are being increasingly used in animal nutrition as appetizers, digestive and physiological stimulants, colorants, and antioxidants, and for the prevention and treatment of certain pathological conditions. The digestive effects of herbs and spices have been tested primarily in humans and laboratory animals, and few trials have been performed on farm animals. Studies on the dietary inclusion of herbs and spices or their extracts in rabbit meat production are quite scarce, and the overall benefit remains unclear due to discrepancies in results, such as the use of plant preparations as galactagogues in rabbit does. Some positive results have been shown their potential, however. The dietary inclusion of Foeniculum vulgare Mill. seeds with oregano leaves has been observed to improve diet utilization, whereas the dietary inclusion of a mixture of Lupinus albus L., Trigonella foenum-graecum L., and Cassia senna L. has acted as growth promoter. Antimicrobial effects are derived especially from plant volatile oils. In the rabbit, a stabilizing effect on microbiota was observed when the diet was supplemented with thyme oil. When diets were supplemented with thyme leaves and spirulina algae, an antimicrobial effect on Clostridium coccoides, Clostridium leptum in the caecum was observed. Black cumin seeds have been shown to exert anti-inflammatory, anti-bacterial and immunomodulatory effects. Several herbs and spices (green tea, rooibos, oregano, rosemary and thyme) provide antioxidant effects rabbit dietary supplementation or inclusion in meat and meat products. Research in the use of herbs or/and spices has demonstrated their potential as feed additives and/or antioxidants, but further research is recommended to optimize effects on rabbits before practical proposals can be drafted.


      PubDate: 2016-05-19T23:03:46Z
       
  • Causal relationships between clinical mastitis events, milk yields and
           lactation persistency in US Holsteins
    • Abstract: Publication date: July 2016
      Source:Livestock Science, Volume 189
      Author(s): K. Dhakal, F. Tiezzi, J.S. Clay, C. Maltecca
      Complex relationships exist between udder susceptibility to mastitis and milk production traits. Identifying causal association between these traits could help to disentangle these complex relationships. The main objective of the study was to use producer-recorded health data to examine the causal relationship between mastitis events, milk yield and lactation persistency. A total of 48,058 first lactation cows, daughters of 2213 Holstein bulls and raised across 207 herds were analyzed using structural equation models. Traits included in the dataset were mastitis events and average test day milk yields recorded in three different periods: period 1 (5–60 DIM), period 2 (61–120 DIM) and period 3 (121–180 DIM). In addition, lactation persistency was also included. A subset including 28,867 daughters of 1809 Holstein sires having both first and second lactation across 201 herds was further investigated. In these datasets, mastitis events were defined on a lactation basis as binary trait; either a cow was assigned a score of 1 (had a mastitis event in that lactation) or a score of 0 (healthy) for that particular lactation, regardless of the time of occurrence. Total milk yield from first and second lactation were also included in the analyses. We estimated negative structural coefficient (−0.032) between clinical mastitis and test day milk production in early lactation period suggesting that mastitis results in a direct decline in milk production in early lactation. We nonetheless elicited little impact of mastitis on test day milk production of mid and late lactation periods, and on milk yield lactation persistency. Likewise the positive estimate of the structural coefficient (0.123) from mastitis event in first lactation to second lactation suggests an increased risk of mastitis in second lactation if a case of mastitis occurs in the primiparous cow. Heritability estimates obtained from the structural equation models were low for mastitis (ranged 0.04 to 0.07), and negative genetic correlations were found between mastitis events and milk yield. The study illustrates how mastitis events and production are causally linked. Through the use of structural equation models we elicited the causal effect among mastitis and production traits that evolve over the course of cow life.


      PubDate: 2016-05-13T22:35:04Z
       
  • Factors and determinants of animal genetic resources management activities
           across the world
    • Abstract: Publication date: Available online 13 May 2016
      Source:Livestock Science
      Author(s): G. Leroy, B. Besbes, P. Boettcher, I. Hoffmann, D. Pilling, R. Baumung, B. Scherf
      This paper investigates the factors affecting the implementation of various management activities related to the characterization, use and conservation of animal genetic resources (AnGR) across countries. The 128 official country reports provided for The Second Report on the State of the World's Animal Genetic Resources for Food and Agriculture were analysed based on a multivariate approach. These reports investigated topics related the national level of AnGR diversity, the extent of characterization activities, use and breeding programmes and conservation activities, as well as capacities in AnGR management and the use of biotechnologies related to livestock breeding. A large part of the variability (34.7%) of the dataset could be explained by one synthetic variable, which could be interpreted as the general extent of AnGR related activities, and indicate that country efforts on AnGR are directed relatively homogenously towards the various activities and species considered. This variable differentiated mainly OECD and BRICS countries from less developed ones. OECD and BRICS countries also appeared to be differentiated with respect to the use of some specific biotechnologies such as cloning, genetic modification and transplantation of gonadal tissues. With regards to economic and development indicators, the first synthetic variable showed large correlation with the number of researchers in agricultural sciences per inhabitant (r=0.643) and national GDP (r=0.516). Capacities in research therefore appeared to be one of the main enabling forces for activities related to AnGR and the implementation of the Global Plan of Action (GPA) for AnGR.


      PubDate: 2016-05-13T22:35:04Z
       
  • Dynamics of salivary immunoglobulin A and serum interleukin 6 levels in
           newborn calves
    • Abstract: Publication date: July 2016
      Source:Livestock Science, Volume 189
      Author(s): Stephani Fischer, Sophie Diers, Rolf Bauerfeind, Claus-Peter Czerny, Stephan Neumann
      Mucosal immunoglobulin A (IgA) is an important component of the adaptive first line immune defense. Especially in newborn calves, where diarrheal pathogens can cause severe diseases, the adaptive mucosal immunity is crucial. Regulating local IgA production is complex. Cytokines and in particular, interleukin 6 (IL-6), are described to be main actors in this process. In vaccination trails, IL-6 is used to improve the immune response with ambiguous results. Therefore, this study investigated the influence of IL-6 on the physiological development of salivary IgA production in newborn calves. Ten clinically healthy female Holstein calves were sampled over a period of four weeks. Immunoglobulin A and IL-6 were measured in serum, colostrum, milk and saliva. In addition, to compare the mucosal immune response with the systemic immune response, immunoglobulin G was measured in serum, colostrum and milk, too, using a commercial enzyme-linked immunosorbent assay (ELISA). In order to determine the ability of newborn calves to produce IL-6 actively by themselves, the relative gene expression was analyzed in peripheral blood mononuclear cells (PBMC) using a quantitative reverse transcriptase polymerase chain reaction (qPCR). Interleukin 6 gene expression in PBMCs was detected directly after birth. A significant positive correlation between serum IL-6 and salivary IgA was found on day seven (p=0.043). Furthermore, the IL-6 serum concentration peaked on day 14 and coincided with a remarkable IgA increase in saliva (p<0.01). Therefore, IL-6 seemed to play a role during the first initialization phase of a local IgA response.


      PubDate: 2016-05-13T22:35:04Z
       
  • Antimicrobial activity of plant-food by-products: A review focusing on the
           tropics
    • Abstract: Publication date: July 2016
      Source:Livestock Science, Volume 189
      Author(s): J.L. Guil-Guerrero, L. Ramos, C. Moreno, J.C. Zúñiga-Paredes, M. Carlosama-Yepez, P. Ruales
      This review characterizes the antimicrobial potential of agricultural by-products from tropical countries, assessing their suitability as substitutes for antibiotics in animal-production farms. This study responds to an increasing trend in the use of antibiotics and other growth promoters in farm animals in tropical areas. Such use is intended to improve the daily gastrointestinal welfare and also to provide resistance or prevention against acute or chronic diseases, such as infectious diarrhoea and inflammatory bowel diseases. Such diseases pose a major challenge in all countries, but tropical conditions encourage the survival of bacteria and pathogens and commensal bacteria more than in temperate climates, and therefore tropical countries need particular attention in order to solve this dilemma. Fortunately, as a substitute to antibiotics, these countries have considerable antimicrobial potential in plants – that is, agricultural by-products contain a diverse pool of bioactive compounds with antimicrobial properties, which could be employed as feed supplements to improve animal health. By-products from tropical countries constitute rich sources of bioactive compounds, such as phenolics, carotenoids, essential oils, active peptides, saponins, and sterols. Among reviewed by-products, high activity has been detected for avocado seeds, cocoa bean shell, and banana peels, while for isolated pure compounds, high activity has been reported for: alkaloids from lupine and capsaicin; phenolics such as gallic and chlorogenic acids, naringin, exiguaflavanone D, and kenusanone A; and saponins from Capsicum seeds. Some by-product extracts have shown minimum inhibitory concentration (MIC) values very close to that of their isolated pure components. In conclusion, plant-food by-products of tropical origin contain diverse active compounds which act effectively against most pathogenic bacteria tested, avoiding well-characterized cell damage.


      PubDate: 2016-05-13T22:35:04Z
       
  • Short communication: Field-trial evaluation of an automatic temperature
           
    • Abstract: Publication date: Available online 13 May 2016
      Source:Livestock Science
      Author(s): Birte Tietgen, Hans-Joachim Laue, Martina Hoedemaker, Steffi Wiedemann
      The assessment of the rectal temperature plays an important role in the early detection of bovine respiratory disease (BRD) in young calves, but the measurement is invasive and labor-intensive. The aims of this retrospective field-trial evaluation were to assess the correlation between the automatic measurements of the reticulo-ruminal (ReRu) temperature and the rectal temperature and to evaluate the diagnostic accuracy of a cumulative sum (CUSUM) control chart to detect pre-weaned calves suffering from BRD. In 150 male fattening calves (16.6 ± 3.3 d at arrival) the ReRu-temperature was obtained every 5min automatically with a wireless device over a period of 8 weeks. Data was averaged over periods of 30min and 4–6h (day periods). The 30-min means were further evaluated using CUSUM control charts. All calves were inspected by trained persons at least twice a day and rectal temperatures were measured in calves showing visible signs related to BRD. A ReRu hyperthermia (ReRu temperature ≥ 40°C) was detected in 139 calves over 30min and in 99 calves over day periods, respectively. During the evaluation period 30 animals were affected by BRD (rectal temperatures ≥ 40°C and one additional clinical sign). The correlations between rectal temperatures and both the corresponding 30min as well as the day period ReRu temperatures was r = 0.75. The sensitivity (Se) and specificity (Sp) of ReRu hyperthermia for the 30min means to detect BRD were 77% and 97%, respectively, whereas means of the day periods had a Se of 61% and a Sp of 97%. The CUSUM test revealed a Se of 71% and Sp of 98% to detect BRD. On average, by the CUSUM method calves with clinical signs of BRD were identified 3.5 d earlier. In conclusion, the automated ReRu temperature measurement possesses potential for the early detection of febrile responses in very young calves warranting further investigations.


      PubDate: 2016-05-13T22:35:04Z
       
  • Host-parasite ecology of keds (Melophagus ovinus (L.)) relative to sheep
           breed and age on Wyoming rangeland
    • Abstract: Publication date: Available online 5 May 2016
      Source:Livestock Science
      Author(s): John D. Scasta, K. Koepke
      Sheep keds (Melophagus ovinus (L.)), an obligate external parasite of economic concern, are a continual problem in high-elevation grazing situations in most temperate sheep productions areas of the world. The influence of sheep breed, age, and the interaction of breed⁎age on host-parasite ecology, could inform integrated keds management strategies. We measured ked density and presence/absence on Rambouillet, Hampshire, and Suffolk ewes in Wyoming, USA to determine the role of breed, ewe age, and breed⁎age interaction on ked parasitism. Eighteen ewes per breed group were examined for ked presence and ked density with sub-groups within each breed of 1, 2, and 3+ years of age. We used a generalized linear mixed model (GLMM) to analyze the effect of breed, age, and the interaction of breed and age, on a stacked response variable ‘ked infestation’ that is a function of both ked presence and density. Ked infestations differed by ewe age (p = 0.0153; F = 4.55) and by ewe breed (p = 0.0178; F = 3.30). Ked infestation increased with ewe age, as 29% of yearling ewes had keds and 63% of three-year old ewes had keds. Ked infestation was the greatest on the fine-wool Rambouillet ewes (72% presence; 1.4 keds per ewe), and was lower on the medium-wool breeds (Hampshire ewes had 39% presence and 1.0 keds per ewe and Suffolk ewes had 22% presence and 0.3 keds per ewe). The breed⁎age interaction did not significantly influence ked infestation in our joint model of the stacked bivariate ked infestation response outcome (p = 0.1292; F = 1.75). The lack of a significant interaction is attributed to the relatively large variance around the mean for such small breed-age sub-groups and warrants additional study. Our results have implications for parasite management as 100% of three-year old Rambouillet ewes had keds present, but none of the yearling Suffolk ewes had any keds and only 29% of three-year old Suffolk ewes had keds present. The results from our study indicate keds do discriminate by breed perhaps due to an ecological adaptation for a wool-environment that is dense and comprised of a long staple -- features characteristic of the Rambouillet ewes in our study. Integrated ked management strategies could manipulate this host-parasite ecology by selecting resistant breeds and/or strategically treating the most susceptible ewes. For example, this could be all Rambouillet ewe ages or only Suffolk ewes > 2 years of age.


      PubDate: 2016-05-07T22:18:18Z
       
  • Gastrointestinal transport of calcium and phosphate in lactating goats
    • Abstract: Publication date: Available online 7 May 2016
      Source:Livestock Science
      Author(s): Svenja Starke, Julia Reimers, Alexandra S. Muscher-Banse, Bernd Schröder, Gerhard Breves, Mirja R. Wilkens
      Previous studies gave evidence for the assumption that in contrast to sheep, dairy goats can adapt to lactation-induced challenges of calcium (Ca) homeostasis by effective adaptation of gastrointestinal Ca absorption. Ca and phosphate (Pi) homeostasis are known to be closely related challenged during lactation. However, for both, Ca and Pi homeostasis, the underlying molecular mechanisms and their regulation during lactation in goats have only marginally been investigated so far. Therefore, the present study aimed to investigate the impact of lactation on gastrointestinal Ca and Pi absorption in dairy goats on a functional level using the Ussing chamber technique to determine macromineral fluxes across gastrointestinal epithelia, and on a structural level by analyzing gastrointestinal RNA and protein expression of key genes involved in transcellular Ca and Pi transport. Besides slightly increased functional Ca absorption and elevated expression of transient receptor potential vanilloid channel type 6, calbindin D 9K and plasma membrane Ca 2+ -ATPase type 1 in jejunum, an upregulation of Ca absorption in lactating goats also occurred in the rumen in terms of increased Ca fluxes. However, the exact molecular and regulatory mechanisms have to be examined in more detail. Interestingly, intestinal Pi absorption in duodenum and jejunum was downregulated by lactation on functional level, and in accordance, sodium-dependent P i cotransporter type IIb RNA and protein expression were decreased in jejunum. Whether this downregulation of intestinal Pi absorption can be attributed to sufficient Pi supply from endogenous sources or to lactation-induced increased dietary Pi intake has still to be investigated.


      PubDate: 2016-05-07T22:18:18Z
       
  • Plant and natural product based homemade remedies manufactured and used by
           farmers of six central Swiss cantons to treat livestock
    • Abstract: Publication date: Available online 5 May 2016
      Source:Livestock Science
      Author(s): Tinetta Bischoff, Christian R. Vogl, Silvia Ivemeyer, Franziska Klarer, Beat Meier, Matthias Hamburger, Michael Walkenhorst
      The use of medicinal plants and other natural multicomponent remedies might be one measure to reduce the use of antibiotics in livestock. Ethnoveterinary research has the potential to identify promising natural remedies. The knowledge about remedies for livestock was collected from farmers in six central Swiss cantons, Glarus, Obwalden, Nidwalden, Schwyz, Zug and Uri. Between February and April 2013 49 interviews with 63 farmers (25 females and 38 males, aged 24 to 74) were conducted. We collected information on the manufacturing of 370 homemade remedies. Of these, 114 contained no plants, 26 contained a mixture of two to five plants, and 230 contained one plant species (defined as homemade single-herbal remedy report (HSHR)). These 230 HSHRs represented 68 plant species belonging to 35 different botanical families. Thirteen species were reported for the first time for ethnoveterinary use in Switzerland. Matricaria recutita, Calendula officinalis, Urtica dioica and Coffea were the most frequently used ingredients of HSHR. A total of 278 use reports (UR) were described for the 230 HSHR, (233 UR for treating cattle). Treatment of skin disorders (QD), gastrointestinal diseases and metabolic dysfunction (QA) were the most frequently mentioned uses for these remedies. Fewer uses were linked to treatments of the respiratory system (QR), the genito-urinary (QG) and musculo-skeletal systems (QM). In the categorie QA the most UR were described for Matricaria recutita, Linum usitatissimum, and Camellia sinensis. Quercus robur was mainly used to treat diarrhoea in calfs, Coffea Arabica to treat general gastrointestinal troubles, colic, abdominal pain or diarrhoea, and Arthemisia absinthium to treat general gastro-intestinal disorders, diarrhoea or lack of appetite. For four orally administered plant species (Artemisia absinthium, Avena sativa, Citrus x limon, Quercus robur) daily oral doses were determined for the first time (median: 0.03, 6.16, 0.01 and 0.58g dry plant equivalent per kg0.75). In the category QD the most often described plant species were Calendula officinalis, Matricaria recutita, Picea abies, Sanicula europaea and Senecio ovatus. For the latter two plant species we determined for the first time an ethnoveterinary based concentration in the finished product (median: 0.13 and 0.39g dry plant equivalent per 100g finished product). Medicinal plants are known, and used by farmers of central Switzerland mostly for treatment of skin and gastrointestinal diseases. According to recent pharmaceutical and human clinical research several plant species documented in this ethnoveterinary study are worth to be further investigated in clinical trials with livestock.


      PubDate: 2016-05-07T22:18:18Z
       
  • Genetic parameters for harmony and gaits in Hispano-Arabe horses estimated
           by Bayesian methods and Restricted Maximum Likelihood
    • Abstract: Publication date: June 2016
      Source:Livestock Science, Volume 188
      Author(s): M.M. Gómez, L.T. Gama, J.M. León, J. Fernández, S.A. Attalla, J.V. Delgado
      Genetic parameters for harmony and gaits (walk, trot and canter) were estimated in the Hispano-Arabe horse breed. The data set included 12,957 records of 901 animals, collected from 2000 to 2014, and was analysed by Bayesian procedures (Gibbs Sampling) and Restricted Maximum Likelihood. The multivariate animal model with repeated records included management group, sex, combination of year and event of evaluation, season of evaluation as fixed effect, plus age at classification and proportion of Arabian genes as linear covariates and additive genetic, permanent environmental and judge as random effects. Bayesian heritability/repeatability estimates for harmony, walk, trot and canter were 0.18/0.35, 0.10/0.18, 0.13/0.27 and 0.13/0.20, respectively, with standard errors from 0.02 to 0.05. Estimates of additive genetic correlations among harmony and gaits traits ranged from 0.45 to 0.83, and were stronger between harmony and trot or canter than between walk and trot. Analyses by Restricted Maximum Likelihood yielded similar results, and correlations between breeding values estimated by both procedures ranged from 0.80 to 0.94.


      PubDate: 2016-05-07T22:18:18Z
       
  • Investigating mutual relationship among milk fatty acids by multivariate
           factor analysis in dairy cows
    • Abstract: Publication date: Available online 25 April 2016
      Source:Livestock Science
      Author(s): G. Conte, A. Serra, P. Cremonesi, S. Chessa, B. Castiglioni, A. Cappucci, E. Bulleri, M. Mele
      The interpretation of mutual relationship among milk fatty acids (FA) is not easy due to the high number of FA contained in milk fat and to the high degree of correlation among them. Multivariate analysis includes different statistical approaches that could help explaining complex pattern of variables. In this study, Multivariate Factor Analysis (MFA) was used to decompose the correlation matrix of 47 FA and milk production traits (milk yield and protein and fat content) measured in 300 Italian Holstein Friesian cows reared in the North of Italy in 23 commercial dairy farms, representative of the intensive dairy system. MFA was able to extract seven latent factors with specific biologic meaning: secretion of Long Chain FA (KLCFA), mammary FA de novo synthesis (Km), rumen biohydrogenation (Kbh), synthesis of odd chain FA (Ko), synthesis of branched chain FA (Kb), mammary desaturation activity (Kd), milk yield (Kmy). According to the pattern of communalities of the factor analysis, C18:3c9c12c15 was the only FA, along with C18:2t11c15, to be uncorrelated with the other variables and it seemed to be excluded by the metabolic pattern described by the seven factors. The desaturation products of the SCD enzyme were independently associated to three latent factors, suggesting new insights in the regulation of SCD activity. Factors were considered as new quantitative phenotypes related to prominent features of milk FA profile. With the aim of evaluating the feeding regimen and animal effects, latent factors were analysed with a mixed model, which considered the fixed effect of lactation stage, parity, some feeding regimen characteristics and the random effect of bull. Lactation stage significantly affected Km and Kmy factors. In perspective, the seven factors extracted by applying MFA analysis to milk FA composition could be considered as new and more informative traits to test the effect of endogenous and exogenous variation factors.


      PubDate: 2016-04-27T21:32:50Z
       
  • Homogeneity and heterogeneity of variance components for milk and protein
           yield at different cluster sizes in Iranian Holsteins
    • Abstract: Publication date: Available online 26 April 2016
      Source:Livestock Science
      Author(s): Jamshid Ehsaninia, Navid Ghavi Hossein-Zadeh, Abdol Ahad Shadparvar
      This study was conducted to investigate the homogeneity and heterogeneity of variance components for milk yield (MY) and protein yield (PY) at different cluster sizes and to evaluate effect of different data transformation methods on the ranking of elite animals in Iranian Holsteins. Data included 305-day lactation records for MY and PY from the first three lactations that were collected in the period from 1983 to 2014 by the Animal Breeding Center and Promotion of Animal Products of Iran. The mean and standard deviation of 305-day MY and PY for each herd were obtained and used as the basis for clustering the herds. Four different data transformation methods including Logarithmic, Arc sin, Square root and Box-Cox were applied and the data were tested for heterogeneity of variance before and after transformation using Bartlett's test. Genetic parameters and heritability estimates as well as animals’ breeding values (BVs) were estimated by the VCE program, using animal model. The results indicated the heterogeneity of variance in all clusters (P<0.01) before transformation. All methods of data transformation decreased the heterogeneity of variance components for MY and PY in the first three lactations and some of these methods caused removing the heterogeneity of variance. Results showed that the heritability estimates of MY and PY were decreased from the first lactation to third, also heritability estimates of transformed data were slightly higher than the original data ones. Some re-ranking of animals occurred from the transformation, but the Box-Cox method only had slight effects on the overall ranking and rank correlations of animals. The applied data transformation caused a substantial re-ranking of elite sires and dams in the EBV for each cluster. This study provided evidence that the applied transformation methods reduced the bias in the EBVs due to heterogeneous variances and increased the accuracy of bull-dam selection. Therefore, effects of heterogeneous variances need to be accounted for in genetic evaluation of Holstein cows in Iran.


      PubDate: 2016-04-27T21:32:50Z
       
  • Genomic-polygenic and polygenic evaluations for milk yield and fat
           percentage using random regression models with Legendre polynomials in a
           Thai multibreed dairy population
    • Abstract: Publication date: Available online 27 April 2016
      Source:Livestock Science
      Author(s): Danai Jattawa, Mauricio A. Elzo, Skorn Koonawootrittriron, Thanathip Suwanasopee
      The objectives of this research were to compare estimates of variance components, genetic parameters, prediction accuracies, and rankings of animals for 305-d milk yield (305-d MY) and 305-d fat percentage (305-d FP) from random regression genomic-polygenic (RRGM) and random regression polygenic (RRPM) models. In addition, RRGM and RRPM prediction accuracies and rankings were compared with those from a standard cumulative 305-d genomic-polygenic model (SCGM). The dataset contained first-lactation monthly test-day records (69,029 for MY and 29,878 for FY) from 7,206 Holstein-upgraded cows located in 761 Thai farms. Genotypic data included 74,144 actual and imputed SNP from 1,661 animals. Variance components and genetic parameters were estimated using REML procedures. The RRGM and RRPM included contemporary group (herd-year-season), calving age, heterosis, and third-order Legendre population regression coefficients. Random effects were animal additive genetic third-order Legendre regression coefficients, permanent environment third-order Legendre regression coefficients, and residual. The SCGM contained contemporary group (herd-year-season), calving age and heterosis as fixed effects, and additive genetic and residual as random effects. The RRGM yielded higher additive genetic variances and heritabilities for 305-d MY and 305-d FP than RRPM, whereas correlations between MY and FY were similar in both models. The highest prediction accuracies for both traits were for RRGM, followed by RRPM, and the lowest ones were from SCGM. Similarly, the highest rank correlations were between animal EBV for 305-d MY and 305-d FP from RRGM and RRPM, followed by those between RRGM and SCGM, and the lowest ones were between RRPM and SCGM. The higher heritability estimates and higher prediction accuracies for RRGM than for RRPM and SCGM indicated that higher selection responses for 305-d MY and 305-d FP may be achieved in this Thai dairy population by utilizing a random-regression model and genotypic information in addition to phenotypes and pedigree.


      PubDate: 2016-04-27T21:32:50Z
       
  • The effect of alfalfa saponins on the contractility of bovine isolated
           abomasum and duodenum preparations
    • Abstract: Publication date: Available online 26 April 2016
      Source:Livestock Science
      Author(s): Marta Mendel, Magdalena Chłopecka, Natalia Dziekan, Wojciech Karlik
      Saponins, a vast group of secondary plant metabolites, occur naturally in plants that are commonly present in ruminants’ diet or plants that are used as phytogenic feed additives. They have gained particular attention among ruminant nutritionists due to numerous health benefits resulting in improved animal performance and feed conversion efficiency. Despite the broad knowledge of saponins’ effects of on cattle, little is known about their impact on gut motility. Therefore, the effect of two structurally divergent alfalfa saponins on the contractility of abomasum and duodenum smooth muscle was examined. The study was conducted on tissues obtained from routinely slaughtered, healthy cows. The experiments were carried out on longitudinal and circular smooth muscle preparations under isometric conditions. The effect of hederagenin and medicagenic acid in a concentration range of 0.001–100µM was verified in a non-cumulative manner on acetylcholine-precontracted smooth muscle specimens. The results are expressed as percentage of the control contraction induced by acetylcholine. Generally, both triterpenoid saponins caused significant enhancement of acetylcholine-induced contraction of abomasum and duodenum preparations. Hederagenin generated dose-dependently significant increase of acetylcholine-evoked contraction of abomasum strips. The strongest contraction caused by hederagenin in a concentration of 100µM was observed in abomasal circular smooth muscle and amounted to 184.1±15.5% of the control treatment. Similarly, in case of duodenum hederagenin increased smooth muscle contractility dose-dependently. Hederagenin applied in the highest tested concentration doubled the force of acetylcholine-induced contraction in duodenal longitudinal smooth muscle. Medicagenic acid caused a remarkable increase of abomasum but not duodenum smooth muscle contractility. The contractile effect of medicagenic acid was observed in a concentration range of 0.001–10µM. The highest contractions of abomasal longitudinal and circular smooth muscle generated by medicagenic acid exceeded 150% of the control treatment with acetylcholine. All reactions caused by hederagenin and medicagenic acid were reversible and did not abolish the spontaneous motoric activity of specimens. Taking into consideration the physicochemical properties of saponins it is postulated that the contractile effect of hederagenin and medicagenic acid results from their impact on the fluidity or plasticity of the membrane and subsequently the ion flow through cell membrane. The increased ability of cells to depolarize can explain the enhancement of the response to acetylcholine. The reversibility of induced contractions, preserved spontaneous contractility and remained reactivity of smooth muscle after saponin treatment indicate that the effect caused by alfalfa saponin does not result from cell membrane damage.
      Graphical abstract image

      PubDate: 2016-04-27T21:32:50Z
       
  • The complete mitochondrial DNA sequence of the Montecristo goat
    • Abstract: Publication date: Available online 22 April 2016
      Source:Livestock Science
      Author(s): Maria Grazia Doro, Giuseppina Casu, Giovanni Giuseppe Leoni, Salvatore Naitana, Mario Pirastu, Andrea Novelletto, Fulvio Fraticelli
      The remote island of Montecristo is renowned for a resident goat population, whose origins are unclear. We describe the complete mtDNA sequence of a male specimen captured on the island. The sequence turned out to belong to haplogroup (Hg) A. Our results exclude that the sequence belongs to a lineage more closely related to bezoars than domestic goats. The lineages most similar to the Montecristo sequence are currently found in Western Europe, favouring partial feralization for the Montecristo isolate. Positioning of the Montecristo mitogenome in the emerging phylogenetic tree for domestic goats reveals a new lineage with multiple derived nucleotide states shared with lineages so far described in Europe as well as in North Asian breeds. This reveals the presence, within Hg A, of lineages with a palearctic distribution, whose descendants are now grown from Eastern Asia to Western Europe.


      PubDate: 2016-04-22T21:15:27Z
       
  • Analysis of the rumen bacteria and methanogenic archaea of yak (Bos
           grunniens) steers grazing on the Qinghai-Tibetan Plateau
    • Abstract: Publication date: Available online 13 April 2016
      Source:Livestock Science
      Author(s): Dan Xue, Huai Chen, Fang Chen, Yixin He, Chuan Zhao, Dan Zhu, Lile Zeng, Wei Li
      Yak is an important domesticated ruminant on the Qinghai-Tibet Plateau in China. The prokaryotic community of yak remains largely uncharacterized when compared to that of other livestock species. In the present study, high-throughput sequencing of 16S rRNA genes (targeting bacterial and archaeal) and clone library of mcrA gene (targeting methanogenic archaea) were applied to investigate the rumen prokaryotic community structure. High-throughput sequencing results indicated that the rumen prokaryotic community consisted of 29 phyla, 40 classes, 63 orders, 77 families, and 79 genera. Bacteroidetes (59.1%) was the most abundant phylum, followed by Firmicutes, Proteobacteria, Fibrobacteres and Euryarchaeota. Prevotella was the predominant genus, averaging 28.5% of all rumen prokaryotic genera. Archaea accounted for 2.26% of the total prokaryotic community, with their community dominated by Methanobacteriaceae (82%), followed by Methanomassiliicoccaceae, and Methanosarcinaceae. Compared with the clone library of mcrA gene, high-throughput sequencing of 16S rRNA genes yielded a greater coverage of methanogenic archaea diversity. However, both molecular techniques showed that Methanobrevibacter is the predominant archaea of rumen microbiota in yaks grazing natural pastures. Our results should facilitate understanding of the complex rumen ecosystem and the main process of ruminal methanogenesis, which may help to further mitigate CH4 emissions from ruminants.


      PubDate: 2016-04-17T15:52:43Z
       
  • Intake, total and partial digestibility of nutrients, and ruminal kinetics
           in crossbreed steers fed with multiple supplements containing spineless
           cactus enriched with urea
    • Abstract: Publication date: Available online 13 April 2016
      Source:Livestock Science
      Author(s): C.T.F. Costa, M.A. Ferreira, J.M.S. Campos, A. Guim, J.L. Silva, M.C.B. Siqueira, L.J.A. Barros, T.D.Q. Siqueira
      Multiple supplements are used in pasture-based systems to manage deficits in the forage, and they can be composed of a controller mixture (e.g. urea + mineral mixture) to regulate the intake of the animals. The effect of using spineless cactus enriched with urea in place of traditional multiple supplements was evaluated for nutrient intake, partial and total digestibility, and ruminal kinetics in crossbred steers. Five steers, ½ Holstein x Zebu, with permanent cannulas in the rumen and with an average initial body weight of 240±22.1kg, were used in a 5×5 Latin square. The treatments consisted of four levels of inclusion of urea (0, 1, 2, and 3% in dry matter (DM) and a control treatment with a traditional multiple supplement. The Tifton-85 hay, used as forage, had high neutral detergent fiber (659g NDF kg−1 of DM) and low crude protein (62g CP kg−1 of DM) content. There was a linear increase in the intake of CP and a quadratic effect in intake of dry matter (DM), organic matter (OM), non-fiber carbohydrates (NFC), NDF, and digestible OM according to the urea inclusion level. The maximum point for total OM digestibility (645g kg−1) was with the inclusion of 2% urea. There was an improvement in ruminal digestibility of DM, NDF, and CP when spineless cactus was enriched with urea. The ruminal pool of DM, NDF, and iNDF did not change with the inclusion of urea in the diets. Increased intake rate (ki) was observed when spineless cactus was enriched with urea. The passage rate (kp) of spineless cactus enriched with 3% urea was similar to the control diet. The rate of NDF degradation increased in the diets enriched with spineless cactus. It is suggested that spineless cactus enriched with up to 2% urea efficiently replaces traditional multiple supplements.


      PubDate: 2016-04-17T15:52:43Z
       
  • Feed Restriction Alters Lipogenic and Adipokine Gene Expression in
           Visceral and Subcutaneous Fat Depots in Lamb
    • Abstract: Publication date: Available online 12 April 2016
      Source:Livestock Science
      Author(s): Jinli Yang, Xinxing Lu, Xianzhi Hou, Hairong Wang, Caixia Shi, Guichao Wang, Shuqing Wu, Aiwu Gao
      Currently, lipogenic and adipokine gene expression patterns in different fat depots during long-term feed restriction in growing lambs are poorly understood. This study aimed to determine the effects of long-term nutritional deficiency on lipogenic and adipokine gene expression in subcutaneous and visceral fat depots in lambs. Twenty male lambs (4 months old; 21.81±0.75kg body weight) were randomly assigned to either control or feed-restricted groups. After 60 days of maintenance-level feed restriction, femoral, omental, mesenteric, epicardial, and perirenal fat were collected. Gene expressions were estimated by quantitative real-time PCR, and plasma parameters were also determined. The results showed that feed restriction increased the plasma concentration of NEFA (P<0.05) at 30 days, and decreased the plasma concentration of triglycerides, glucose, and insulin (P<0.05) at 30 days and 60 days. Feed restriction decreased lipogenic gene expression (acetyl coenzyme A carboxylase alpha and fatty acid synthase) in all five fat depots. The related key regulating gene PPARγ mRNA decreased (P<0.05) in femoral, omental, and mesenteric fat depots, while sterol regulatory element binding transcription factor 1 decreased (P<0.05) in femoral fat depots. Perilipin, as a barrier to lipolysis, decreased (P<0.05) in femoral, omental and perirenal fat depots of the feed restriction group. Adipose tissue-derived hormone leptin mRNA decreased (P<0.05) in all five fat depots, while adiponectin decreased (P<0.05) only in omental, mesenteric, and epicardial depots. Macrophage marker CD68 mRNA increased (P<0.05) in femoral and mesenteric fat depots. In addition, tumor necrosis factor-α mRNA increased in femoral, omental, and mesenteric depots, whereas IL-1β mRNA increased in femoral and perirenal depots. IL-6 expression decreased in femoral, omental, and epicardial fat depot at the end of feed restriction. Nutritional deficiency induced different changes in lipogenic and adipokine gene expression between visceral and subcutaneous adipose tissue. The decreased leptin, adiponectin, and increased inflammatory factors may inhibit lipogenesis and stimulate lipolysis to protect the body against the threat of starvation.


      PubDate: 2016-04-17T15:52:43Z
       
  • Influence of carbohydrate source on digesta kinetics and postprandial
           glucose responses of broiler chicks
    • Abstract: Publication date: Available online 8 April 2016
      Source:Livestock Science
      Author(s): O.O. Adeleye, A.D. Ologhobo, B.T. Oje-Adetule
      This study was conducted to investigate the effect of different carbohydrates included in the diets of broiler chicks on digesta kinetics and postprandial plasma glucose responses. Starch extracted from different energy feedstuffs, maize, wheat, millet, sweet potato, and cassava, was used as the main energy source in each diet. Ninety 1-d-old broiler chicks were assigned to 5 diets containing 45±3% of each starch with 3 replicates and 6 broiler chicks per replicate. The digesta kinetics study involved administering 50mg chromic oxide orally to each broiler chick before feeding. Excreta produced was collected hourly for the first 8h and 10, 12, 24, 36, and 48h, and their Cr2+content determined. Cumulative Cr2+excretion, times at 1 (T1) and 50% (T50) Cr2+excretion, time at peak Cr2+excretion, and mean retention time (MRT) were estimated. Two broiler chicks per replicate were used for the plasma glucose response study where glucose concentration was measured from blood collected from the wing vein of each broiler chick up to 480min postprandial. Postprandial glucose responses, as well as hydrolysis indices were calculated. Digesta transit time variables, T1, T50, time at peak Cr2+excretion, and MRT varied and were greatest for cassava starch diet at 0.2, 6.20, 8.00, and 19.45h, respectively, and least for the sweet potato starch diet at 0.1, 4.2, 5.0, and 17.20h, respectively. Plasma glucose response variables also varied considerably (P<0.05) between treatments and were attributed to starch granule size and dimensions. However, no relationship was observed between digesta kinetics and postprandial glucose responses of broiler chicks fed the experimental diets.


      PubDate: 2016-04-12T15:37:14Z
       
  • Polymorphism in the SCD gene is associated with meat quality and fatty
           acid composition in Iranian fat- and thin-tailed sheep breeds
    • Abstract: Publication date: Available online 11 April 2016
      Source:Livestock Science
      Author(s): Mohsen Aali, Hosein Moradi-Shahrbabak, Mohammad Moradi-Shahrbabak, Mostafa Sadeghi, Hamid Kohram
      The enzyme stearoyl-coenzyme A-desaturase (SCD) has been proposed as a key regulator for fat content and fatty acid composition of meat. In this study, a DNA sequence and single-strand confirmation polymorphism analysis were performed in an attempt to investigate the relationship between variation within the SCD gene and fatty acid profiles, physicochemical composition, and the quality characteristics of longissimus dorsi (LD) muscle in two traditional fat- (Chall) and thin- (Zel) tailed Iranian sheep breeds. Only one previously reported SNP (g.379A>T) located in the 5′ untranslated region of the SCD gene was observed. Two previously reported allelic variants, SCD−1 and SCD−2, constituted two previously reported genotypes, “A” and “B”. Based on t-test, no allelic and genotypic frequency differences were observed between Chall and Zel breeds. Lambs with genotype “B” significantly had lower total saturated fatty acid (SFA) level (p<0.05) and more linoleic (p<0.02), arachidonic (p<0.002), and eicosapentaenoic (EPA) (p<0.001) acids and total poly-unsaturated fatty acid (PUFA) (p=0.002) contents and PUFA:SFA ratio (p<0.004) than those with genotype “A”. Meat color of the genotype “B” lambs was lower for a⁎ (p<0.05) and higher for L⁎ (p<0.08) compared to the genotype “A” ones. There were some interactions between breed and SCD gene in terms of palmitic acid (p<0.04), cooking loss (p<0.05), and protein content (p<0.03) of LD muscle. SCD locus explained 17.3%, 15.3%, 13%, and 12% of the phenotypic variation in terms of EPA and arachidonic acid, and PUFA contents and PUFA:SFA ratio, respectively. Interestingly, the results of the correlation analyses showed the significant negative correlations between healthy fatty acid indices (PUFA and PUFA:SFA) and meat color measures of a⁎ and b⁎ (r=−0.26 to r=−0.40, p<0.05) and the significant positive correlations between n−6:n−3 PUFA, one of the main harmful fatty acid indices, and a⁎ (r=0.41, p<0.01) and b⁎ (r=0.27, p<0.05) values which are coordinated with the effect of SCD genotypes on fatty acid composition and color of meat. So, both fatty acid composition and meat color traits should be considered in marker-assisted selection based on SCD gene. Overall, it seems that the genotype “B” of SCD gene is a more desirable genotype when selecting lambs in terms of both fatty acid composition and color of meat, because selecting this genotype would result in higher proportion of healthy fatty acids, lower proportion of harmful fatty acids, and better meat color.


      PubDate: 2016-04-12T15:37:14Z
       
  • Characteristics of runs of homozygosity in selected cattle breeds
           maintained in Poland
    • Abstract: Publication date: Available online 11 April 2016
      Source:Livestock Science
      Author(s): Tomasz Szmatoła, Artur Gurgul, Katarzyna Ropka-Molik, Igor Jasielczuk, Tomasz Ząbek, Monika Bugno-Poniewierska
      Runs of homozygosity (ROH) are defined as contiguous homozygous regions of the genome where the two haplotypes inherited from the parents are identical. It has been shown that the length and frequency of ROH may describe the history of the population in which an individual occurs; they may also reveal the level of inbreeding within populations, recent population bottlenecks or signatures of positive selection. In this study, BovineSNP50 whole-genome genotyping assay was used to analyse the lengths and distributions of the ROH found in the genomes of four cattle breeds maintained in Poland (Holstein, Polish Red, Limousin and Simmental) to assess both the level of autozygosity of each breed and to identify the genomic regions most commonly associated with ROH that may reflect directional selection pressure. Visible differences in the length and distribution of homozygous regions across the genome between selected breeds were observed. The breeds also varied in the level of autozygosity (inbreeding) estimated by FROH, which was lower for unselected cattle. Moreover, within the regions of the genome most commonly associated with ROH that may reveal signatures of recent selection a number of genes potentially connected with different production features characteristic for individual breeds were detected.


      PubDate: 2016-04-12T15:37:14Z
       
  • Enhancement of daily gain and feed efficiency of growing heifers by
           dietary supplementation of β-mannanase in Hanwoo (Bos taurus
           coreanae)
    • Abstract: Publication date: Available online 4 April 2016
      Source:Livestock Science
      Author(s): Jakyeom Seo, Jeongsoo Park, Junsung Lee, Jae-Hwan Lee, Jung-Jin Lee, Dong Keun Kam, Seongwon Seo
      β-mannanase is an enzyme that breaks down mannan which is complex biopolymers commonly found in plant cell walls. It has been reported that supplementation of β-mannanase in a diet that composed of high mannan containing feedstuffs (e.g. palm kernel meal, copra meal, soy hull; HMCF) improves digestibility and utilization of livestock feeds. In ruminants, β-mannanase supplementation also increased growth rate of goats and Holstein calves. No study, however, has been conducted to evaluate the effect of β-mannanase supplementation in growing heifers. Moreover, little is known whether β-mannanase supplementation will have beneficial effects in conventional corn-soy based diets (CS). The objective of this study was thus to investigate the effect of supplementation of β-mannanase in Hanwoo growing heifers fed a diet composed of either a CS or HMCF based concentrate mix. For this purpose, a feeding trial was conducted for 12 weeks using a total of 40 Hanwoo growing heifers (BW: 236.2kg±1.1kg, 11 month of age). Total mixed rations (250g/kg of ryegrass and 750g/kg of concentrate mix) were offered ad libitum. The experimental design was 2×2 factorial approach with two different concentrate mixes (CS or HMCF based) and with or without a commercial feed β-mannanase (800,000U/kg DM) product (CTCZYME®, CTC Bio Inc., Seoul, Korea) at a level of 1g/kg in concentrate mixes. In both diets, supplementation of β-mannanase significantly increased ADG of Hanwoo heifers by 95g/d on average (111g/d or 90g/d for CS and HMCF, respectively). No significant difference was observed in DMI among treatments, but β-mannanase supplementation tended to decrease feed conversion ratio (DMI/ADG) by 1.3 on average. The ADG of CS (943g/d) was significantly greater than that of HMCF (854g/d). These results indicated that supplementation of β-mannanase enhanced growth rate and feed efficiency of Hanwoo heifers regardless of the basal diets. Therefore, we conclude that supplementation of β-mannanase can be beneficial to improve the feed utilization in Hanwoo growing heifers.


      PubDate: 2016-04-07T04:54:53Z
       
  • A complex of trypsin and chymotrypsin effectively inhibited growth of
           pathogenic bacteria inducing cow mastitis and showed synergistic
           antibacterial activity with antibiotics
    • Abstract: Publication date: Available online 28 March 2016
      Source:Livestock Science
      Author(s): X.H. Zhang, Z. Wang, B. Yin, H. Wu, S. Tang, L. Wu, Y.N. Su, Y. Lin, X.Q. Liu, B. Pang, N. Kemper, J. Hartung, E.D. Bao
      The objective of this research was to assess the inhibitory effects of a complex of trypsin and chymotrypsin alone and in combination with antibiotics, on pathogenic bacteria involved in cow mastitis in vitro. We also conducted investigations of the antimicrobial mechanism and primary treatment trials on infected cattle. The presence of trypsin (0.16mg/mL) alone only clearly hindered the growth of Streptococcus agalactiae (CVCC586) and Streptococcus dysgalactiae (ATCC12388). Chymotrypsin (0.16mg/mL) alone, and the complex of trypsin and chymotrypsin at the dose C (0.16mg/mL trypsin + 0.16mg/mL chymotrypsin) or 2C showed varying inhibitory effects on all the tested bacterial strains, including Escherichia coli (ATCC8739), Pasteurella (C51-3), Staphylococcus aureus (ATCC25923). The experiments also indicated that the complex of trypsin and chymotrypsin could hydrolyze bacterial outer-membrane proteins, damage the integrity of surface structures, and lead to leakage of intracellular material such as alkaline phosphatase, glucose and DNA. The complex of Trypsin and chymotrypsin showed well synergistic antibacterial effects when combined with specific antibiotics. In the field trial on 20 cows naturally suffering from clinical mastitis, the complex of trypsin and chymotrypsin reduced effectively Streptococcus, E. coli, S. aureus, and some other Enterobacteriaceae as well as the somatic cell counts in milk samples of treated cattle compared to controls. The complex of trypsin and chymotrypsin, and its combination with antibiotics, seems to have a potential in clinical veterinary medicine to treat mastitis.


      PubDate: 2016-04-03T04:36:01Z
       
  • Technical Note: Can tail arterial or tail venous blood represent external
           pudic arterial blood to measure amino acid uptake by mammary gland of
           cows?
    • Abstract: Publication date: Available online 1 April 2016
      Source:Livestock Science
      Author(s): Y.D. Zhang, D.P. Bu, S.C. Li, N. Zheng, X.Q. Zhou, M. Zhao, S.G. Zhao, S.L. Li, J.Q. Wang
      Sampling blood from the artery supply and venous drainage of the udder of dairy cows is essential for estimating the uptake of amino acids (AA) by the mammary gland using the arteriovenous difference approach. Since it is difficult to sample blood form the external pudic artery, finding a representative alternative was necessary. In this experiment, 13 lactating Holstein dairy cows were used to validate whether blood from the tail artery or tail vein could be used a substitute for external pudic arterial blood for calculation of amino acid (AA) extraction rate by the mammary gland. The results showed that no significant differences were noted in the individual AA concentration (P>0.10) between the tail arterial, tail venous blood and external pudic artery, except for Asp, Thr and Pro. The calculated extraction rates based on the A-V difference between the external pudic artery, tail artery or tail vein and the subcutaneous vein were not different for individual AA (P>0.10) except for those rates for Asp, Thr and Glu (P<0.10). These results indicated that blood sample from the tail artery or tail vein could be used as an alternative to external pubic arterial blood for studying the uptake of most AA, but not for Asp, Thr and Glu, by the mammary gland of dairy cows.


      PubDate: 2016-04-03T04:36:01Z
       
  • Enteric methane emissions and nitrogen utilisation efficiency for two
           genotype of hill hoggets offered fresh, ensiled and pelleted ryegrass
    • Abstract: Publication date: Available online 31 March 2016
      Source:Livestock Science
      Author(s): Y.G. Zhao, A. Aubry, R. Annett, N.E. O’Connell, T. Yan
      Thirty-six 12-month-old hill hoggets were used in a 2 genotype (18 Scottish Blackface vs. 18 Swaledale × Scottish Blackface)×3 diet (fresh vs. ensiled vs. pelleted ryegrass) factorial design experiment to evaluate the effects of hogget genotype and forage type on enteric methane (CH4) emissions and nitrogen (N) utilisation. The hoggets were offered 3 diets ad libitum with no concentrate supplementation in a single period study with 6 hoggets for each of the 6 genotype × diet combinations (n=6). Fresh ryegrass was harvested daily in the morning. Pelleted ryegrass was sourced from a commercial supplier (Aylescott Driers & Feeds, Burrington, UK) and the ryegrass silage was ensiled with Ecosyl (Lactobacillus plantarum, Volac International Limited, Hertfordshire, UK) as an additive. The hoggets were housed in individual pens for at least 14 d before being transferred to individual respiration chambers for a further 4 d with feed intake, faeces and urine outputs and CH4 emissions measured. There was no significant interaction between genotype and forage type on any parameter evaluated. Sheep offered pelleted grass had greater feed intake (e.g. DM, energy and N) but less energy and nutrient apparent digestibility (e.g. DM, N and neutral detergent fibre (NDF)) than those given fresh grass or grass silage (P<0.001). Feeding pelleted grass, rather than fresh grass or grass silage, reduced enteric CH4 emissions as a proportion of DM intake and gross energy (GE) intake (P<0.01). Sheep offered fresh grass had a significantly lower acid detergent fibre (ADF) apparent digestibility, and CH4 energy output (CH4-E) as a proportion of GE intake than those offered grass silage (P<0.001). There was no significant difference, in CH4 emission rate or N utilisation efficiency when compared between Scottish Blackface and Swaledale × Scottish Blackface. Linear and multiple regression techniques were used to develop relationships between CH4 emissions or N excretion and dietary and animal variables using data from sheep offered fresh ryegrass and grass silage. The equation relating CH4-E (MJ/d) to GE intake (GEI, MJ/d), energy apparent digestibility (DE/GE) and metabolisability (ME/GE) resulted in a high r2 (CH4-E=0.074 GEI + 9.2 DE/GE – 10.2 ME/GE – 0.37, r2=0.93). N intake (NI) was the best predictor for manure N excretion (Manure N=0.66 NI + 0.96, r2=0.85). The use of these relationships can potentially improve the precision and decrease the uncertainty in predicting CH4 emissions and N excretion for sheep production systems managed under the current feeding conditions.


      PubDate: 2016-04-03T04:36:01Z
       
  • Non-invasive measures of oral-rectal transit in young pigs
    • Abstract: Publication date: Available online 18 March 2016
      Source:Livestock Science
      Author(s): Andre Y.F. Tan, Magdy Sourial, John M. Hutson, Bridget. R. Southwell
      The gastrointestinal transit of markers in pigs has been well studied, but the methods and approaches are different from gastrointestinal studies performed in humans clinically. Aim: To develop a non-invasive method of estimating oral-rectal transit times in young pigs. Methods: We performed transit studies in 3 groups of 4 week-old, Large White female pigs. Group 1. Ten animals (5.7±0.34kg (mean ± SEM)) were fed blue-dyed grower feed and placed under video surveillance. Group 2a. Twenty-two animals (7.7±0.59kg) from the same pig supplier were administered 18 4mm-diameter radio-opaque plastic markers under light anaesthesia (5% isofluorane), and we took abdominal x-rays at 6, 30, 54 and 78hours. Group 2b. Eight pigs (9.2±0.48kg) from a different supplier also underwent plastic marker transit studies. Results: Using blue dye (fluid transit), the median (25th, 75th percentiles) time to first incidence of blue-dyed stool was 13.2 (10.2, 18.1) hours and to last blue stool was 24.1 (22.4, 40.3) hours. Using plastic markers, markers were evacuated between 30 and 80+hours with differences in stomach emptying between two groups of animals from different farms. Median oral-rectal transit times were 25.2 (17.8, 40.5) hours and 48.9 (26.9, 68.3) hours in the second and third groups (M-W test, P=0.04). Conclusion: There are differences in the transit of fluid- and solid-phase marker in pigs. Fluid-phase markers appear earlier than solid markers. Monitoring the evacuation of fluid-phase dye using video surveillance is difficult. Using plastic markers and x-rays to estimate the segmental and oral-rectal transit times in young pigs may be a useful method that can be correlated to oral-rectal transit studies performed in humans. The ability of pigs to hold solids in the stomach for extended times complicates transit studies. There are some differences in transit in pigs from different breeders.


      PubDate: 2016-03-23T13:01:01Z
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
Home (Search)
Subjects A-Z
Publishers A-Z
Customise
APIs
Your IP address: 54.80.244.61
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2015