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Journal Cover Livestock Science
  [SJR: 0.837]   [H-I: 81]   [6 followers]  Follow
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1871-1413
   Published by Elsevier Homepage  [3042 journals]
  • High-fiber rapeseed co-product diet for Norwegian Landrace pigs: Effect on
    • Authors: M. Pérez de Nanclares; M.P. Trudeau; J.Ø. Hansen; L.T. Mydland; P.E. Urriola; G.C. Shurson; C. Piercey Åkesson; N.P. Kjos; M.Ø. Arntzen; M. Øverland
      Pages: 1 - 9
      Abstract: Publication date: September 2017
      Source:Livestock Science, Volume 203
      Author(s): M. Pérez de Nanclares, M.P. Trudeau, J.Ø. Hansen, L.T. Mydland, P.E. Urriola, G.C. Shurson, C. Piercey Åkesson, N.P. Kjos, M.Ø. Arntzen, M. Øverland
      The effect of partially replacing soybean meal (SBM) and wheat with high-fiber rapeseed (RS) co-products on the nutrient and energy digestibility of 40 Norwegian Landrace pigs (17.8 ± 2.7kg initial BW) was investigated. Pigs were fed a pelleted diet containing 200g/kg of a coarse fraction of air-classified rapeseed meal (RSM) and 40g/kg of RS hulls or a SBM control diet (20 pigs/dietary treatment) for 3 wk to estimate apparent ileal (AID) or total tract (ATTD) digestibility of energy and nutrients, organ weight, intestinal histomorphology, and digestive enzyme activities of individual pigs. Feeding high-fiber RS co-products increased (P = 0.004) the thyroid to body weight ratio and reduced (P < 0.05) the AID and ATTD of energy, dry matter, organic matter, crude protein (CP), neutral detergent fiber, acid detergent fiber, P, and most of the amino acids (AA) and monosaccharides. The reduction in digestibility was not associated with morphological changes in ileum or colon. The reduced AID of CP and AA coincided with a decrease (P = 0.030) in trypsin activity in the jejunum. The AID of starch was not affected by the dietary treatment, which also coincided with similar amylase and maltase activities in the jejunum. Variation in nutrient digestibility was observed among individual pigs within each dietary treatment. In conclusion, feeding high-fiber RS co-products to pigs enlarged the thyroid gland and reduced the AID and ATTD of most nutrients and energy. The reduction in digestibility was not associated with changes in intestinal morphology, but correlated with digestive enzyme activities.

      PubDate: 2017-06-27T14:36:02Z
      DOI: 10.1016/j.livsci.2017.06.008
      Issue No: Vol. 203 (2017)
  • Effects of different levels of canola meal peptides on growth performance
           and blood metabolites in broiler chickens
    • Authors: Sadegh Karimzadeh; Mansour Rezaei; Asadollah Teimouri Yansari
      Pages: 37 - 40
      Abstract: Publication date: September 2017
      Source:Livestock Science, Volume 203
      Author(s): Sadegh Karimzadeh, Mansour Rezaei, Asadollah Teimouri Yansari
      This study was conducted to evaluate the effects of canola meal peptides (CMP) on growth performance, blood metabolites, and antioxidant activities in broiler chickens. A total of 250 one-day-old male broiler chickens were randomly allocated to 5 dietary treatments with 5 pens and 10 broiler chickens in each pen. The broiler chickens were fed the basal diets supplemented with 0, 100, 150, 200, or 250mg CMP/kg for 42 d. With increasing the supplementation of CMP in the basal diet, body weight gain increased and feed conversion ratio decreased both linearly and quadratically from d 0 to 42 (P < 0.01). Supplementation of the basal diet with CMP increased (linear, P < 0.01) serum lysozyme and superoxide dismutase activities and immunoglobulin M concentrations at d 42. Serum cholesterol and triglyceride concentrations decreased linearly and quadraticaly (P < 0.01), but total protein increased linearly and quadratically (P < 0.01) and P and Ca increased linearly (P < 0.01) as dietary supplementation of CMP increased from 0 to 250mg/kg at d 21 and 42. The results indicated that the dietary supplementation of CMP can increase performance, blood metabolites, and antioxidant activities in broiler chickens.

      PubDate: 2017-07-08T15:08:44Z
      DOI: 10.1016/j.livsci.2017.06.013
      Issue No: Vol. 203 (2017)
  • Polymorphisms in the SOX9 region and testicular disorder of sex
           development (38,XX; SRY-negative) in pigs
    • Authors: Monika Stachowiak; Izabela Szczerbal; Joanna Nowacka-Woszuk; Hanna Jackowiak; Pawel Sledzinski; Pawel Iskrzak; Stanislaw Dzimira; Marek Switonski
      Pages: 48 - 53
      Abstract: Publication date: September 2017
      Source:Livestock Science, Volume 203
      Author(s): Monika Stachowiak, Izabela Szczerbal, Joanna Nowacka-Woszuk, Hanna Jackowiak, Pawel Sledzinski, Pawel Iskrzak, Stanislaw Dzimira, Marek Switonski
      Testicular XX disorder of sex development (XX DSD, SRY-negative), causing sterility, is quite frequently diagnosed in pig populations, however, its molecular background is still unknown. This disorder may affect carcass quality (boar taint) due to the presence of testicular tissue in animals with ambiguous female external genitalia. A chromosome fragment encompassing the SOX9 gene was previously considered as a candidate region in functional and association studies. We analyzed distribution of polymorphic variants in 5’UTR and in 3’-flanking regions of the SOX9 gene in a cohort of 12 XX DSD pigs and a panel of 116 normal females. Altogether, 8 previously known polymorphic sites were analyzed and no significant association under Bonferroni correction (P>0.0063) between DSD phenotype and identified SNPs was found. The region harboring the SOX9 gene was also searched for the presence of copy number variation (CNV) by fluorescence in situ hybridization technique (FISH), using a set of 7 BAC probes. A potential CNV region, manifested by size variation (large and small) of fluorescence signals, produced by a single BAC probe hybridizing downstream (approx. 500kb) of the SOX9 gene, was observed in 4 DSD cases. We conclude, that a new CNV polymorphism in the region harboring SOX9 gene can be considered as a promising marker for the DSD phenotype.

      PubDate: 2017-07-08T15:08:44Z
      DOI: 10.1016/j.livsci.2017.07.002
      Issue No: Vol. 203 (2017)
  • Hepatic proteome changes induced by dietary supplementation with two
           levels of native chicory inulin in young pigs
    • Authors: Agnieszka Herosimczyk; Adam Lepczyński; Małgorzata Ożgo; Marcin Barszcz; Edyta Jaszczuk-Kubiak; Mariusz Pierzchała; Anna Tuśnio; Jacek Skomiał
      Pages: 54 - 62
      Abstract: Publication date: September 2017
      Source:Livestock Science, Volume 203
      Author(s): Agnieszka Herosimczyk, Adam Lepczyński, Małgorzata Ożgo, Marcin Barszcz, Edyta Jaszczuk-Kubiak, Mariusz Pierzchała, Anna Tuśnio, Jacek Skomiał
      Inulin-type prebiotics are known as health-promoting dietary components and still remain a promising alternative to replace antibiotics for improving performance of young animals. Recent studies have proven that dietary inulin may positively affect the liver transcriptomic profile. However, its effect on the hepatic proteome in growing pigs is largely unknown. Therefore, the aim of the study was to gain insight into the effect of dietary supplementation with two inulin levels on the accumulation of the hepatic proteins and expression of selected genes. The experiment was carried out on a total of 24 castrated male piglets, which were assigned to three groups, fed from the 10th day of life an unsupplemented cereal-based diet or diets supplemented with 1% or 3% of native chicory inulin. Liver and blood samples were collected after 40 days of feeding and liver proteins were resolved using two-dimensional electrophoresis. To check whether modifications in accumulation of selected proteins were due to higher levels of mRNA and not due to decrease in protein degradation, real-time PCR was employed. Feeding diet with 3% of inulin induced significant down-accumulation of proteins involved in cytoskeleton organization and four isoforms of 14-3-3 protein and its mRNA. Both levels of inulin had also the potential to induce the expression of genes and accumulation of proteins directly or indirectly involved in controlling hepatic triglycerides level by increasing its lipolysis to fatty acid and glycerol. Dietary supplementation with inulin significantly increased liver cholesterol and TG concentration but decreased total plasma cholesterol and HDL cholesterol levels, and additionally reduced fibrinogen concentration, especially at 3% dietary level. Inulin level did not affect plasma liver enzymes, albumin, total protein content and immunoglobulin G levels. In conclusion, 1% of inulin is not sufficient to exert its effects on changes in hepatic protein expression, whereas feeding diet with the 3% inulin addition down-regulates expression of proteins involved in organization of cytoskeleton in hepatocytes and affects lipid metabolism in the liver causing alterations in expression of specific proteins, greater accumulation of cholesterol and TG, and changes in lipid profile of blood plasma.

      PubDate: 2017-07-08T15:08:44Z
      DOI: 10.1016/j.livsci.2017.07.004
      Issue No: Vol. 203 (2017)
  • A genome wide association study between CNVs and quantitative traits in
           Brown Swiss cattle
    • Authors: R.T.M.M. Prinsen; A. Rossoni; B. Gredler; A. Bieber; A. Bagnato; M.G. Strillacci
      Pages: 7 - 12
      Abstract: Publication date: Available online 17 May 2017
      Source:Livestock Science
      Author(s): R.T.M.M. Prinsen, A. Rossoni, B. Gredler, A. Bieber, A. Bagnato, M.G. Strillacci
      Copy Number Variations (CNVs) are DNA sequences of 50bp up to several Mb long, which can vary in number of copies in comparison with a reference genome. CNVs can be used in association studies to disclose genetic basis of quantitative traits phenotypic variation. Up to date, no genome-wide association study (GWAS) with CNVs and quantitative traits in such a large Brown Swiss population (i.e. with 1,116 samples) has been described. The purpose of this study was to perform a GWAS using CNVs with functional, health and productive traits and to asses the impact on farming and breeding practices. The CNV – association studies were performed with the Golden Helix SVS 8.4.4 software using a correlation-trend test model. Genes within significant associated CNVs for each trait were annotated with a GO analysis using the DAVID Bioinformatics Resources 6.7. A total of 56 CNVs were significantly associated with one or more of the eight evaluated traits. The greatest association signals were given by three CNVs on chromosome 12 for the fat yield trait and on BTA23 for udder traits. The associated CNVs overlap with 23 different genes annotated on the Bos taurus genome assembly (UMD3.1).

      PubDate: 2017-05-20T12:34:56Z
      DOI: 10.1016/j.livsci.2017.05.011
      Issue No: Vol. 202 (2017)
  • Genomic-polygenic and polygenic predictions for nine ultrasound and
           carcass traits in Angus-Brahman multibreed cattle using three sets of
    • Authors: M.A. Elzo; R.G. Mateescu; D.D. Johnson; T.L. Scheffler; J.M. Scheffler; C. Carr; D.O. Rae; J.G. Wasdin; M.D. Driver; J.D. Driver
      Pages: 58 - 66
      Abstract: Publication date: August 2017
      Source:Livestock Science, Volume 202
      Author(s): M.A. Elzo, R.G. Mateescu, D.D. Johnson, T.L. Scheffler, J.M. Scheffler, C. Carr, D.O. Rae, J.G. Wasdin, M.D. Driver, J.D. Driver
      The objectives of this study were to estimate variance components, genetic parameters, EBV, accuracies, and rankings for nine ultrasound and carcass traits in a multibreed Angus-Brahman population using three genomic-polygenic models and one polygenic model (PM). The genomic-polygenic models used the complete GeneSeek GPF250k SNP set (GPM), top 5% SNP (GPMR1), and 5% SNP evenly spread across the genome (GPMR2). Yearling ultrasound traits were weight (UW), ribeye area (UREA), backfat (UFAT), and percent intramuscular fat (UPIMF). Carcass traits were slaughter age (SLA), hot carcass weight (HCW), ribeye area (REA), backfat thickness (FAT), and marbling score (MAR). The 9-trait GPM, GPMR1, GPMR2, and PM contained fixed contemporary group, age of calf (ultrasound traits only), sex of calf, and direct heterosis effects, and random animal and residual effects. Variance components and genetic parameters were computed using AIREMLF90. Comparable heritabilities were obtained with GPM and PM for UW (GPM: 0.54 ± 0.05; PM: 0.51 ± 0.05), UREA (GPM: 0.36 ± 0.03; PM: 0.34 ± 0.03), UFAT (GPM: 0.12 ± 0.02; PM: 0.11 ± 0.02), UMPIMF (GPM: 0.34 ± 0.03; PM: 0.30 ± 0.03), SLA (GPM: 0.59 ± 0.07, PM: 0.61 ± 0.06), HCW (GPM: 0.58 ± 0.06, PM: 0.52 ± 0.07), REA (GPM: 0.48 ± 0.04, PM: 0.45 ± 0.05), FAT (GPM: 0.41 ± 0.05, PM: 0.30 ± 0.05), and MAR (GPM: 0.56 ± 0.07, PM: 0.51 ± 0.08). Additive genetic correlations between pairs of ultrasound and carcass traits were all between −0.31 and 0.81. The highest positive additive genetic correlations were between UW and UREA, UW and HCW, UW and REA, UREA and HCW, UREA and REA, UFAT and FAT, and between HCW and REA. The largest negative additive genetic correlations were between UREA and UPIMF, UFAT and SLA, UFAT and HCW, UPIMF and REA, and between REA and MAR. High similarity existed among predicted EBV and accuracies from GPM, GPMR1, and GPMR2 as well as high-rank correlations for sires, dams, and progenies. This indicated that the two reduced genotype sets were appropriate alternatives to the complete GPF250k set for genomic-polygenic evaluation and selection in this multibreed Angus-Brahman population. High EBV variability existed among animals of all Angus and Brahman percentages and no specific breed composition was overwhelmingly better or worse for any of the nine traits. This indicated that optimization of genetic progress through selection in multibreed Angus-Brahman populations should be based solely on genetic merit regardless of breed composition.

      PubDate: 2017-06-05T13:01:08Z
      DOI: 10.1016/j.livsci.2017.05.027
      Issue No: Vol. 202 (2017)
  • Gene expression patterns in Korean native ducks (Anas platyrhynchos) with
           different Apparent Metabolisable Energy (AME) levels
    • Authors: Jaesung Cho; Jiyeon Jeong; Yelin Jeong; Jung Min Heo; Inchul Choi
      Pages: 67 - 73
      Abstract: Publication date: Available online 26 May 2017
      Source:Livestock Science
      Author(s): Jaesung Cho, Jiyeon Jeong, Yelin Jeong, Jung Min Heo, Inchul Choi
      Quantitative energy changes in the feeding regimens affect metabolic efficiency and product quality of an animal. Apparent metabolisable energy (AME) is used to evaluate energy utilization such as the difference between the energy consumed and the energy lost. Given the importance of the diet in the profitability we focused on determination of AME levels using biomarkers based on molecular techniques. qRT-PCR was performed to determine gene expression differences in ducklings with different metabolisable energy (ME) levels and potential biomarker genes from circulating mRNA in the body fluid based on estimated AME values. Muscle tissues and cell-free plasma samples were obtained from ducklings fed at three different ME levels (basal ME: 2,300; AME: 2,900; high ME: 3,300kcal/kg diet). We first identified that 18S ribosomal RNA was the most suitable endogenous reference gene for determining gene expression analysis. Next, we investigated expression levels of genes related to cell growth, proliferation, oxidative stress, myogenic differentiation, adipocyte differentiation, and mitochondrial function. qRT-PCR assay demonstrated that MAPK8, MAP2K4, HADHA, CSRP3, and MYL1 were gradually up-regulated at the AME and high ME levels. However, PRKAG2, CRH, and PPARG transcript levels were significantly increased in the muscle and the cell-free plasma at the excessive high ME level but not at the AME and the basal ME level. Finally, HSP90AA1 and HSPB7 were not different between AME and high ME level. Our findings suggest that altered patterns of gene expression in response to different levels of energy are useful biomarkers to evaluate the AME value with growing ducklings. Upregulation of genes including MAPK8, PRKAA2, and PRKAG2 at the excessive high ME and their enrichment for lipid and fatty acid biosynthetic process in gene network analysis also supported our molecular approach using circulating nucleic acid in the body fluid.

      PubDate: 2017-05-30T12:57:12Z
      DOI: 10.1016/j.livsci.2017.05.022
      Issue No: Vol. 202 (2017)
  • Upregulated heat shock protein beta-1 associated with caloric restriction
           and high feed efficiency in longissimus dorsi muscle of steer
    • Authors: U.S. Jung; M.J. Kim; T. Wang; J.S. Lee; S.W. Jeon; N.C. Jo; W.S. Kim; M. Baik; H.G. Lee
      Pages: 109 - 114
      Abstract: Publication date: August 2017
      Source:Livestock Science, Volume 202
      Author(s): U.S. Jung, M.J. Kim, T. Wang, J.S. Lee, S.W. Jeon, N.C. Jo, W.S. Kim, M. Baik, H.G. Lee
      The objective of this study was to identify myogenic proteins associated with caloric restriction and feed efficiency in bovine longissimus dorsi muscle. Thirty-one Korean native steers were allocated to 100% ad libitum (n = 16) or 80% of ad libitum (n = 15) groups. Regardless of nutritional level, a subset of these animals were assigned to groups with high or low feed efficiency (n = 5) at a later time point based on feed efficiency. A total of 7 differentially expressed proteins were found between groups with different nutrition levels while a total of 12 differentially expressed proteins were found between groups with different feed efficiencies. Interestingly, heat shock protein beta-1 (HSPB1) was a differentially expressed protein that showed up in both results (nutrition level and feed efficiency). It was up-regulated in both the 80% ad libitum group and the high feed efficiency group. In in vitro study, mRNA expression level of HSPB1 was increased (P < 0.05) after myogenic differentiation. Results of this study suggest that HSPB1 might be a myogenic protein involved in response to caloric restriction and feed efficiency in longissimus dorsi muscle of Korean native steer.

      PubDate: 2017-06-10T13:03:33Z
      DOI: 10.1016/j.livsci.2017.05.009
      Issue No: Vol. 202 (2017)
  • High frequency pre-slaughter electrical stunning in ruminants and poultry
           for halal meat production: A review
    • Authors: A.B. Sabow; K. Nakyinsige; K.D. Adeyemi; A.Q. Sazili; C.B. Johnson; J. Webster; M.M. Farouk
      Pages: 124 - 134
      Abstract: Publication date: August 2017
      Source:Livestock Science, Volume 202
      Author(s): A.B. Sabow, K. Nakyinsige, K.D. Adeyemi, A.Q. Sazili, C.B. Johnson, J. Webster, M.M. Farouk
      The use of high and low electrical frequencies in pre-slaughter electrical stunning and their implications for meat quality and animal welfare in ruminants and poultry are reviewed. There are different views regarding the appropriateness of high and low frequency stunning with respect to religious and animal welfare requirements. High electrical frequency when applied head-to-back does not initiate cardiac arrest, reduces carcass damage, enhances bleeding efficiency and eliminates the need for subsequent electrical immobilization for operator's safety. Conversely, low frequency when similarly applied kills the animal, which has animal welfare advantages, but reduces bleeding efficiency and negatively affects the quality of meat. The ability of high frequency to effectively stun without killing the stunned animal enables the process to meet this fundamental requirement for halal slaughtering when used in head-to-back in ruminants and water bath electrical stunning in poultry. Thus, it is necessary to appraise the efficacy of high and low frequency stunning in order to optimize meat quality and animal welfare attributes vis-a-vis their compliance with halal requirements.

      PubDate: 2017-06-14T13:06:44Z
      DOI: 10.1016/j.livsci.2017.05.021
      Issue No: Vol. 202 (2017)
  • Effects of a traditional Chinese medicine formula supplementation on
           growth performance, carcass characteristics, meat quality and fatty acid
           profiles of finishing pigs
    • Authors: Q.P. Yu; D.Y. Feng; M.H. Xia; X.J. He; Y.H. Liu; H.Z. Tan; S.G. Zou; X.H. Ou; T. Zheng; Y. Cao; X.J. Wu; X.Q. Zheng; F. Wu; J.J. Zuo
      Pages: 135 - 142
      Abstract: Publication date: Available online 7 June 2017
      Source:Livestock Science
      Author(s): Q.P. Yu, D.Y. Feng, M.H. Xia, X.J. He, Y.H. Liu, H.Z. Tan, S.G. Zou, X.H. Ou, T. Zheng, Y. Cao, X.J. Wu, X.Q. Zheng, F. Wu, J.J. Zuo
      This study investigated the effects of a traditional Chinese medicine formula (TCMF) on growth performance, and meat quality and fatty acid profiles of finishing pigs. Ninety 146-day-old Pietrain×Duroc×Landrace×Yorkshire pigs (84.1±0.86kg BW) were assigned randomly to three treatments with five replicates, six pigs per pen. Control group was fed basal diet and the other two groups were fed basal diet plus different doses of the TCMF (TCMF1: 2.5g/kg feed; TCMF2: 5g/kg feed). Growth performance was unaffected by TCMF (P>0.05). Pigs fed the TCMF had higher crude fat content in muscle (P<0.05) and lower level of malondialdehyde (P<0.01) in muscle than those fed with the control diet. The a⁎ values, subjective color scores and marbling scores at TCMF1 dietary treatment were increased (P<0.05), but those at TCMF2 dietary treatment were similar to the control (P>0.05). The concentration of vaccenic acid in longissimus dorsi and of total unsaturated fatty acids in abdominal adipose tissue were increased by TCMF1 (P<0.05), while paullinic acid in subcutaneous fat was increased by TCMF2 (P<0.05). In conclusion, TCMF fed to fattening pigs increased crude fat in meat and reduced lipid oxidation of pork meat.

      PubDate: 2017-06-10T13:03:33Z
      DOI: 10.1016/j.livsci.2017.05.029
      Issue No: Vol. 202 (2017)
  • The milk yield of dams and its relation to direct and maternal genetic
           components of weaning weight in beef cattle
    • Authors: X. Cortés-Lacruz; I. Casasús; R. Revilla; A. Sanz; M. Blanco; D. Villalba
      Pages: 143 - 149
      Abstract: Publication date: August 2017
      Source:Livestock Science, Volume 202
      Author(s): X. Cortés-Lacruz, I. Casasús, R. Revilla, A. Sanz, M. Blanco, D. Villalba
      Cow milk yield is a critical component for the growth of the calves in the preweaning period. The genetic correlation between direct weaning weight and milk yield traits may cause a decrease in the maternal ability of cows when they are selected for the direct weaning weight of the calf. The objective of this study was to analyse the genetic and environmental components of some traits of interest in beef cattle breeds managed in mountain conditions by analysing the actual cumulative milk yield at 150 days obtained by milking (MY150) and the weight at birth (BW), at 90 days (W90), at weaning (W150), and mature weight (MW). Genetic evaluations were conducted using field data from 2679 calves born from 553 dams of Parda de Montaña beef cattle breed. The variances, genetic (both direct and maternal) and phenotypic, were estimated by a multi-trait animal model. Milk yield was correlated with maternal components of calf weight at 90 days and 150 days (genetic correlations of 0.59 and 0.48, respectively) and also correlated with a direct genetic component of W90 and W150 (genetic correlations of 0.58 and 0.54, respectively). The maternal heritability values for W90 and W150 were 0.023 (0.005) and 0.009 (0.004), respectively. The estimates of the direct-maternal genetic correlation for W90 and W150 were − 0.13 (0.11) and − 0.34 (0.16), respectively. Environmental effects, especially the sex of calf and dam parity for direct genetic effects and energy level of cow and body condition at calving for maternal effects, should be included in the evaluation models to obtain a proper estimation of genetic parameters for beef cattle evaluation. Genetic milk yield explains half the variation of maternal effects for W90 and W150. The prediction of milk yield will be better using maternal effects at 90 days than at 150 days. The combined index (maternal and direct) for the trait weight at 150 days yielded the highest economic response increasing the direct effect indirectly without decreasing the maternal effect at 150 days.

      PubDate: 2017-06-14T13:06:44Z
      DOI: 10.1016/j.livsci.2017.05.025
      Issue No: Vol. 202 (2017)
  • Impact of concentrate supplementation during early lactation on the
           performance of grass fed, twin suckling ewes and their progeny
    • Authors: Frank P. Campion; Fiona M. McGovern; Stephen Lott; Philip Creighton; Tommy M. Boland
      Pages: 150 - 158
      Abstract: Publication date: August 2017
      Source:Livestock Science, Volume 202
      Author(s): Frank P. Campion, Fiona M. McGovern, Stephen Lott, Philip Creighton, Tommy M. Boland
      The objective of this study was to investigate the impact of concentrate supplementation during early lactation on grass intake by the lactating ewe and subsequent ewe and lamb performance during the first seven wk post-partum. Fifty-four twin bearing and rearing ewes, were randomly allocated to one of three dietary treatments (n = 18) on d 7 (± two d) of lactation (experimental d zero). Dietary treatments were as follows; GO = zero-grazed grass ad libitum from d 7 to d 49 post-partum, GC = zero-grazed grass ad libitum plus 500g fresh weight (FW) of concentrate supplementation from d 7 to d 49 post-partum, GC21 = zero-grazed grass ad libitum from d 7 to d 49 post-partum plus 500g FW of concentrate supplementation from d 7 to d 21 post-partum. Each ewe was penned independently with her progeny on slatted flooring at 72h post-partum with access to a straw bedded creep for lambs only. Zero-grazed grass was harvested from predominantly perennial ryegrass (Lolium perenne) swards daily at 0730h and cut to a height of 3.5cm. Grass DMI from wk two to seven of lactation was lower for GC ewes than GO (P < 0.01) and GC21 (P = 0.06) ewes. Differences in grass DMI were not reflected in total DMI (P > 0.10) or total OMI (P > 0.10) with total OMI ranging from 1.81 to 1.94kg per ewe per d. Rumen fluid pH dropped during the first seven d of the experiment for GC and GC21 ewes (P < 0.01) and was lower for both these treatments compared to GO ewes at 14 d post-partum (P < 0.01). Ewes from GO tended to have a lower live weight than GC ewes at wk 7 of lactation (P = 0.06). Ewe milk yield varied with treatment at wk seven of lactation with GC ewes producing higher yields than GO and GC21 ewes (P < 0.01). Treatment had no effect on lamb average daily gain during the first six wk post-partum (P > 0.10). The results of this study show that when ewes were offered zero-grazed grass during early lactation, concentrate feeding reduced grass DMI with no improvement in milk yield until wk 7 of lactation.

      PubDate: 2017-06-19T14:31:55Z
      DOI: 10.1016/j.livsci.2017.05.024
      Issue No: Vol. 202 (2017)
  • Bayesian random regression threshold models for genetic evaluation of
           pregnancy probability in Red Sindhi heifers
    • Authors: Lorena Tavares de Oliveira; Cristina Moreira Bonafé; Fabyano Fonseca e Silva; Henrique Torres Ventura; Hinayah Rojas de Oliveira; Gilberto Romeiro de Oliveira Menezes; Marcos Deon Vilela de Resende; José Marcelo Soriano Viana
      Pages: 166 - 170
      Abstract: Publication date: Available online 15 June 2017
      Source:Livestock Science
      Author(s): Lorena Tavares de Oliveira, Cristina Moreira Bonafé, Fabyano Fonseca e Silva, Henrique Torres Ventura, Hinayah Rojas de Oliveira, Gilberto Romeiro de Oliveira Menezes, Marcos Deon Vilela de Resende, José Marcelo Soriano Viana
      We proposed a Bayesian random regression threshold model for genetic evaluation of pregnancy probability (PP) in Red Sindhi heifers over different months. Since this breed was recently introduced in Brazil, the age of 14 months usually preconized for Nellore cattle may not reflect the reality of the fertility indicator. In this context, the pregnancy success was evaluated at other ages aiming to understand its genetic variability pattern over time. A total of 4,828 phenotyped heifers belong to 657 contemporary groups were used for the analysis. The estimated connectedness was equal to 99.75% considering 6,189 individuals in the final pedigree. The random regression threshold models were implemented by combining second, third and fourth order Legendre polynomials to describe the average, the additive genetic and the permanent environmental curves. Additionally, the heterogeneity of the residual variance was also tested here. Based on DIC (deviance information criterion) and posterior model probabilities, the fourth order Legendre polynomials (LEG_4441) for the average, the additive genetic and the permanent environmental effects, assuming homogeneity of the residual variance, outperformed the simplest models. Thus, the fitting quality compensated the increased in the model complexity. The negative genetic correlations between PP at 15 months with PP at latter months indicates that rankings of animals for selection would be few similar in advanced ages. The high values for heritability (varying from 0.32 to 0.45) suggest that PP, mainly until 19 months, can be used as selection criterion for reproductive female performance in breeding programs for Red Sindhi cattle in Brazil. These practical results were only obtained due to the advantages of the proposed random regression threshold models to describe PP over different months.

      PubDate: 2017-06-19T14:31:55Z
      DOI: 10.1016/j.livsci.2017.06.005
      Issue No: Vol. 202 (2017)
  • On the haplotype diversity along the genome in Spanish beef cattle
    • Authors: E.F. Mouresan; A. González-Rodríguez; J.J. Cañas-Álvarez; C. Díaz; J. Altarriba; J.A. Baro; J. Piedrafita; A. Molina; M.A. Toro; L. Varona
      Pages: 30 - 33
      Abstract: Publication date: July 2017
      Source:Livestock Science, Volume 201
      Author(s): E.F. Mouresan, A. González-Rodríguez, J.J. Cañas-Álvarez, C. Díaz, J. Altarriba, J.A. Baro, J. Piedrafita, A. Molina, M.A. Toro, L. Varona
      This study analyzed the haplotype diversity along the genome of seven Spanish Beef Cattle populations within regions of 500kb using the information provided by the BovineHD Beadchip. The results of the analysis pointed out a strong variability of the haplotype diversity across the genome, which is greatly conserved across populations. This strong concordance between populations suggests that the reasons behind it are intrinsic to the structure of the bovine genome and caused probably by the mutation or recombination rate. Nevertheless, some of the genomic regions with very large haplotype diversity are also due of genome assembly errors.

      PubDate: 2017-05-06T14:48:07Z
      DOI: 10.1016/j.livsci.2017.04.015
      Issue No: Vol. 201 (2017)
  • Integrated crop-livestock management practices, technical efficiency and
           technology ratios in extensive small-ruminant systems in Ghana
    • Authors: Bright O. Asante; Renato A. Villano; George E. Battese
      Pages: 58 - 69
      Abstract: Publication date: July 2017
      Source:Livestock Science, Volume 201
      Author(s): Bright O. Asante, Renato A. Villano, George E. Battese
      This paper evaluates the performance of smallholder farmers in three districts of the forest-savannah transition agroecological zone of Ghana and examines the effect of integrated crop-livestock management practices (ICLMPs) on the productivity and technical efficiency of production of small-ruminant outputs of farmers. Using farm-level data collected from a sample of 510 farmers from the Atebubu-Amantin, Nkoranza South and Ejura-Sekyedumase districts, a metafrontier production function model is used to estimate the mean technical efficiencies of farmers in each district and their metatechnology ratios. Small-ruminant outputs of the farmers were significantly influenced by the inputs, herd size, capital, labor, feed and veterinary expenses, in at least one of the three districts and for the metafrontier function. Furthermore, the small-ruminant outputs were significantly and positively influenced by the use of pigeon pea, ash or neem, improved pasture and storage of crop residue. The efficiency of production of small ruminants was affected by ICLMPs such as the use tetracycline, use of ash or neem, and storage of crop residue in one or more of the three districts. The technical efficiency of the crop-livestock farmers was also influenced by their age, gender and education, by their participation in projects, obtaining off-farm income, market information and access to extension advice in one or more of the three districts. The results indicate that there are significant differences in small-ruminant production technologies across the three districts and that the production technology in Nkoranza South district is superior to the ones in use in the other two districts. The results underscore the need for investments in research and extension in developing and disseminating relevant ICLMPs and complementary training that leads to more efficient small-ruminant production and, consequently, increased farm income.

      PubDate: 2017-05-16T12:29:59Z
      DOI: 10.1016/j.livsci.2017.03.010
      Issue No: Vol. 201 (2017)
  • Radiant heat increases piglets’ use of the heated creep area on the
           critical days after birth
    • Authors: M.L.V. Larsen; K. Thodberg; L.J. Pedersen
      Pages: 74 - 77
      Abstract: Publication date: July 2017
      Source:Livestock Science, Volume 201
      Author(s): M.L.V. Larsen, K. Thodberg, L.J. Pedersen
      The aim of the present study was to investigate how piglets’ use of a creep area is affected by using radiant heat compared to an incandescent light bulb. It was hypothesised that radiant heat would increase the use of the creep area. Twenty litters were randomly assigned to one of two heat sources in the creep area: (1) an incandescent light bulb (STANDARD, n=10) or (2) a radiant heat source (RADIANT, n=10) with five of each type of heat source in each of two batches. Observations on piglets’ position in the pen were made by scan sampling every ten minutes in a 4-hour period from 1100 to 1500h on day 1–7, 14 and 21 post partum. A higher percentage of piglets in the creep area was seen for RADIANT litters compared to STANDARD litters on day 2 (P=0.002) and day 3 (P=0.005), and percentage of piglets in the creep area increased for RADIANT litters from day 1 to 2 (P<0.001) and from day 2 to 3 (P=0.03) while it first increased for STANDARD litters from day 2 to 3 (P=0.01). In conclusion, radiant heat gave an earlier and increased use of the creep area on the critical days after birth.

      PubDate: 2017-05-20T12:34:56Z
      DOI: 10.1016/j.livsci.2017.05.008
      Issue No: Vol. 201 (2017)
  • Bayesian Models combining Legendre and B-spline polynomials for genetic
           analysis of multiple lactations in Gyr cattle
    • Authors: Hinayah Rojas de Oliveira; Fabyano Fonseca e Silva; Marcos Vinícius Gualberto Barbosa da Silva; Otávio Henrique Gomes Barbosa Dias de Siqueira; Marco Antônio Machado; João Cláudio do Carmo Panetto; Leonardo Siqueira Glória; Luiz Fernando Brito
      Pages: 78 - 84
      Abstract: Publication date: July 2017
      Source:Livestock Science, Volume 201
      Author(s): Hinayah Rojas de Oliveira, Fabyano Fonseca e Silva, Marcos Vinícius Gualberto Barbosa da Silva, Otávio Henrique Gomes Barbosa Dias de Siqueira, Marco Antônio Machado, João Cláudio do Carmo Panetto, Leonardo Siqueira Glória, Luiz Fernando Brito
      We aimed with this study to combine Legendre polynomials (LEG) and linear B-splines (BSP) to describe simultaneously the first and second lactation of Gyr dairy cattle under a multiple-trait random regression models (MTRRM) framework. Additionally we proposed the application of self-organizing map to define the classes of residual variances under these models. A total of 26,438 and 23,892 milk yield test-day records were used, respectively, for the first and second lactations of 3253 Gyr cows. Two preliminary MTRRM analyses considering 10 residual classes were performed: the first one was based on LEG for systematic and random effects for both lactations; and the second one was based on BSP. Three classes were defined by using a self-organizing map: from 6 to 35; 36–185 and 186–305 days in milk. After definition of residual variance classes, a total of 16 MTRRM combining LEG and BSP were compared. The MTRRM based on BSP to describe the systematic effects of the first and second lactation, BSP to describe the random effects of the first lactation and LEG to describe the random effects of the second lactation (BSP-BSP-BSP-LEG) outperformed all other models. From the BSP-BSP-BSP-LEG model, heritability estimates for milk yield over time ranged from 0.1107 to 0.2902, and from 0.2036 to 0.3967, for the first and second lactation, respectively. In general, additive genetic correlation estimates between days in milk within each lactation and between lactations had medium magnitude (mean of genetic correlations were 0.6630, 0.6226 and 0.4749 for the first, second and between both lactations, respectively). We concluded that combining different functions under a MTRRM framework is a feasible alternative for genetic modeling of lactation curves in Gyr dairy cattle.

      PubDate: 2017-05-20T12:34:56Z
      DOI: 10.1016/j.livsci.2017.05.007
      Issue No: Vol. 201 (2017)
  • Effects of the different levels of dietary vitamin D on boar performance
           and semen quality
    • Authors: Yan Lin; Gang Lv; Hong-Jun Dong; De Wu; Zhi-Yong Tao; Sheng-Yu Xu; Lian-Qiang Che; Zheng-Feng Fang; Shi-Ping Bai; Bin Feng; Jian Li; Xue-Yu Xu
      Abstract: Publication date: Available online 4 July 2017
      Source:Livestock Science
      Author(s): Yan Lin, Gang Lv, Hong-Jun Dong, De Wu, Zhi-Yong Tao, Sheng-Yu Xu, Lian-Qiang Che, Zheng-Feng Fang, Shi-Ping Bai, Bin Feng, Jian Li, Xue-Yu Xu
      Vitamin D plays a major role primarily in bone mineral homeostasis; however, the action of vitamin D on male reproduction of boars remains unknown. This study was conducted to evaluate the effects of dietary vitamin D3 supplementation on reproductive performance of boars. Twenty-four Yorkshire boars with eighteen months were randomly allocated to one of three vitamin D3 levels diets: 200 IU/kg (C), 2000 IU/kg (T1) and 4000 IU/kg (T2) of vitamin D3 for a 16-week period. Results showed that sperm motility, effective sperm number per ejaculate, acrosome intactness ratio, and membrane intactness ratio in T1 group were significantly higher than those in C group. The sperm membrane intactness ratio was higher in T1 group than in T2 group, whereas the deformity ratio was significantly lower in T1 than in C and T2 groups. Dietary supplementation with vitamin D3 significantly increased 25-OHD3 concentration in the blood and seminal plasma, but there was no significant difference in its concentration in the seminal plasma between T1 and T2 groups. The concentrations of blood testosterone and aromatase activity increased following vitamin D supplementation. Seminal plasma Ca2+, fructose concentration, and acid phosphatase activity were higher in T1 group than in C group, but not significantly different from the corresponding values in T2 group. Furthermore, expression of CYP19, CYP24A1, and VDR mRNAs in sperm was up-regulated in T1 group compared to that in C group. In conclusion, supplementation of boar diets with 2000 IU/kg vitamin D3 increased the sperm motility and effective sperm number, which was in line with the elevated concentrations of vitamin D, hormone secretion and gene expression.

      PubDate: 2017-07-08T15:08:44Z
      DOI: 10.1016/j.livsci.2017.07.003
  • Immunocastration: economic implications for the pork supply chain and
           consumer perception. An assessment of existing research
    • Authors: Maria Cecilia; Mancini Davide Menozzi Filippo Arfini
      Abstract: Publication date: Available online 26 June 2017
      Source:Livestock Science
      Author(s): Maria Cecilia Mancini, Davide Menozzi, Filippo Arfini
      The increasing concern of some market segments for animal welfare has led some companies in the pork supply chain to consider immunocastration as an alternative to surgical castration, which is used to prevent boar taint. The first aim of this analysis was to contribute to the systemisation of the literature about the economic and management aspects as well as consumer perception of immunocastration, and the second aim was to provide recommendations for future research to support policy decision making. Some of the observations from the present study include that on the supply chain side, farmers are very cautious about immunocastration despite the scientific evidence of its efficacy, so they require training in vaccine administration and management support to optimise performance as well as completely transparent information on the economic impact of the technique. Further research into the management and economics of alternative techniques would be useful to help farmers and other supply chain stakeholders make better-informed choices. However, the main concern among farmers is consumer perception, and the information collected to date on consumer perception of immunocastration shows important differences between countries that reflect cross-cultural aspects. Overall, there is low awareness of the issue, and few consumers have heard of the vaccine method. Additionally, information campaigns are likely to be more effective if supplementary audio–visual information is used to show surgical castration of live animals and alternative practices. Current research indicates that three main factors influence consumer WTP in terms of different castration techniques: sensitivity to animal welfare, food quality (taste) and food safety. Research has also yielded somewhat controversial findings suggesting that consumers feel the need to trade off attributes that they believe are incompatible (e.g., taste and animal welfare), so publicity and information campaigns are needed to reduce “conflicts” between product attributes that are important to consumer perception. It is necessary to clearly communicate the impact of immunocastration on price, food safety and taste to consumers, particularly in light of the disproportionally large impact of negative publicity related to food safety issues, but sharing information between different stakeholders is also problematic. While there has already been significant research into this topic, the findings need to be adequately disseminated for all stakeholders to be able to make decisions with full awareness.

      PubDate: 2017-06-27T14:36:02Z
  • Measurement of abomasal conditions (pH, pressure and temperature) in
           healthy and diarrheic dairy calves using a wireless ambulatory capsule
    • Authors: Thomas Hildebrandt; Eberhard Scheuch; Werner Weitschies; Michael Grimm; Felix Schneider; Lisa Bachmann; Ingrid Vervuert
      Abstract: Publication date: Available online 23 June 2017
      Source:Livestock Science
      Author(s): Thomas Hildebrandt, Eberhard Scheuch, Werner Weitschies, Michael Grimm, Felix Schneider, Lisa Bachmann, Ingrid Vervuert
      This study investigated abomasal luminal parameters in healthy and diarrheic calves by using a wireless ambulatory capsule (WAC). The acetaminophen absorption test (APAT) was used to determine abomasal emptying rate. Four healthy and five diarrheic female Holstein-Friesian calves (age < 14 days) were included in the study. For APAT, calves were fed 2L of milk replacer containing 50mg acetaminophen/kg body weight, and blood samples were taken during a 12-h period afterward. Concomitantly, a WAC in the abomasum continuously measured luminal pH, pressure, and temperature. Five hours post suckling, intraluminal temperature was significantly higher in diarrheic calves than in healthy calves. Abomasal pH and pressure were not significantly different, but intraluminal pressure was always numerically lower in diarrheic calves. During APAT no significant differences in maximum acetaminophen concentrations (Cmax) and time to reach maximum acetaminophen concentration (Tmax) were observed. Nonlinear regression findings revealed a longer acetaminophen half-time (AAP t1/2) in diarrheic calves compared to healthy calves [564 ± 96min vs. 393 ± 84min, respectively; P = 0.04] and lower area under the concentration curve values (e.g., 60min postprandial AUC60 681 ± 244 (µg∙min)/mL vs. 1064 ± 23 (µg∙min)/mL, respectively; P = 0.04). In conclusion, abomasal luminal conditions were different between diarrheic and healthy calves. Significant differences in APAT reflected a delay in abomasal emptying in diarrheic calves. Impaired abomasal movement may induce enhanced bacterial fermentation processes as indicated by a higher abomasal temperature in diarrheic calves, which should be considered in management of their feeding.

      PubDate: 2017-06-27T14:36:02Z
      DOI: 10.1016/j.livsci.2017.06.011
  • Effects of a dietary supplementation with zinc oxide nanoparticles,
           compared to zinc oxide and zinc methionine, on performance, egg quality,
           and zinc status of laying hens
    • Authors: M. Abedini; F. Shariatmadari; M.A. Karimi Torshizi; H. Ahmadi
      Abstract: Publication date: Available online 22 June 2017
      Source:Livestock Science
      Author(s): M. Abedini, F. Shariatmadari, M.A. Karimi Torshizi, H. Ahmadi
      An experiment was conducted to investigate the effect of diets supplemented with different Zn sources on performance, egg quality, bone parameters, Zn status, superoxide dismutase (SOD) activity, and egg malondialdehyde (MDA) content in laying hens. A total of 192 laying hens at 52 wk of age, with the initial average body weight of 1.53 ± 0.02kg, were randomly assigned to 4 treatments with 4 replicate cages and 12 laying hens per cage. Dietary treatments included the corn-soybean meal based diet (without Zn supplementation), and basal diet supplemented with 80mg Zn/kg diet from Zn oxide-nanoparticles (ZnO-NP), Zn oxide, and Zn-Met. The results showed that dietary Zn supplementation had no effect on feed intake, feed conversion ratio, live body weight, and egg loss. However, the greatest egg production and egg weight observed in ZnO-NP and Zn-Met treatments respectively (P < 0.05). Laying hens fed diets supplemented with ZnO-NP and Zn-Met had a greater egg mass compared to other treatments (P < 0.05). Overall, Zn supplementation increased egg shell weight and Haugh unit (P < 0.05). Dietary ZnO-NP supplementation increased egg shell thickness and egg shell strength, as compared to control (P < 0.05). The bone breaking strength and ash weight was greater in ZnO-NP and Zn-Met treatments, respectively (P < 0.05). The Zn deposition in tibia, liver, pancreas, and egg was greater in laying hens fed ZnO-NP and Zn-Met (P < 0.01). Plasma Zn status was not influenced by treatments. In treatments supplemented with ZnO-NP and Zn-Met, the SOD in the liver and pancreas were greater than the other treatments (P < 0.01). The MDA content in egg was reduced in treatments supplemented with Zn (P < 0.01). In conclusion, this study has shown that supplementation of a diet with ZnO-NP be a suitable source of zinc for laying hens.

      PubDate: 2017-06-27T14:36:02Z
      DOI: 10.1016/j.livsci.2017.06.010
  • Effect of tannins-rich extract from Acacia mearnsii or monensin as feed
           additives on ruminal fermentation efficiency in cattle
    • Authors: F. Perna Junior; E.C.O. Cassiano; M.F. Martins; L.A.S. Romero; D.C.V. Zapata; L.A. Pinedo; C.T. Marino; P.H.M. Rodrigues
      Abstract: Publication date: Available online 20 June 2017
      Source:Livestock Science
      Author(s): F. Perna Junior, E.C.O. Cassiano, M.F. Martins, L.A.S. Romero, D.C.V. Zapata, L.A. Pinedo, C.T. Marino, P.H.M. Rodrigues
      Methane, a powerful greenhouse gas, is considered to be a significant loss of productive potential in ruminants. The objective was to evaluate the effect of monensin and Acacia mearnsii tannins on ruminal fermentation efficiency in cattle. Six rumen-cannulated cows were distributed three diets, each of which differed in the additive used, in a replicated 3×3 Latin square experimental design. Treatments were the Control, Monensin (300mg per animal and day or about 18mg/kg of dry matter - DM) and a tannin-rich extract from Acacia mearnsii (100g per animal and day or about 0.6% of DM). Each experimental period consisted of 21 days; the first 15 days were used for diet adaptation and the last 5 days for data collection. On experimental day 21, ruminal pH was analyzed by a continuous measurement probe. In order to quantify short-chain fatty acids (SCFA), methane (CH4), NH3-N (ammonia nitrogen) production, protozoa and the ruminal dynamics, rumen contents were sampled prior to and 3, 6, 9 and 12hours after morning feeding. The fermentation technique consisted of incubation of liquid and solid rumen contents in bottles in a water bath (39°C) for 30minutes. Subsequent measurement of methane production was made using gas chromatography and used for the final estimation of Relative Energy Loss (REL). There was no effect (P>0.05) of additives on pH, ruminal DM disappearance rate, the concentrations of NH3-N, the production of acetic or butyric acids or the total ruminal SCFA. Monensin treatment was responsible for reducing CH4 production by 10.7%, whereas tannin inclusion reduced it by 8.0%, when compared to the control treatment. The REL was decreased (P<0.05) by 20.3% and 23.8% with tannin and monensin administration, respectively. Additionally, monensin increased propionic acid production by 39.5% when compared to the control treatment (P<0.05); therefore, the short-term use monensin or tannin in diets with the same proportion of roughage and concentrate has shown to be a viable option when formulating cattle diets aimed at improving energy efficiency.

      PubDate: 2017-06-27T14:36:02Z
      DOI: 10.1016/j.livsci.2017.06.009
  • Effect of starch level in supplement with or without oil source on diet
           and apparent digestibility, rumen fermentation and microbial population of
           Nellore steers grazing tropical grass
    • Authors: Antonio Jose Neto; Juliana D. Messana; Yury T. Granja-Salcedo; Pablo S. Castagnino; Giovani Fiorentini; Ricardo A. Reis; Telma T. Berchielli
      Abstract: Publication date: Available online 16 June 2017
      Source:Livestock Science
      Author(s): Antonio Jose Neto, Juliana D. Messana, Yury T. Granja-Salcedo, Pablo S. Castagnino, Giovani Fiorentini, Ricardo A. Reis, Telma T. Berchielli
      In this study, we evaluated the effects of starch level in supplement, with/without whole soybean (oil source), on diet intake and apparent digestibility, rumen microbial population, and fermentation parameters in Nellore steers grazing Brachiaria brizantha cultivar Xaraés during the finishing phase. Eight ruminal cannulated Nellore steers (514kg ± 30) were used in a replicate 4 × 4 Latin square with a 2 × 2 factorial arrangement of treatments. The diets used had different levels of supplemented starch [corn (high) or soybean hulls (SH: low)] with/without a source of oil (soybean grain). There were no interactions between starch level and oil in supplements on the intake of DM (% of body weight, P = 0.602; kg/d, P = 0.703), forage DM (P = 0.630), supplement DM (P = 0.501), OM (P = 0.669), CP (P = 0.420), aNDFom (P = 0.380), EE (P = 0.199) and GE (P = 0.620). However, intake and total apparent digestibility of DM, OM, and aNDFom (P < 0.050) decreased with oil supplementation, whereas the intake and digestibility of aNDFom were increased (P < 0.010) with low-starch supplementation. There were no interactions between starch supplement and oil source supplementation for pH (P = 0.391), NH3-N (P = 0.473), and total volatile fatty acids (P = 0.441). The inclusion of an oil source in supplements decreased (P < 0.010) the acetate concentration in the rumen when compared with supplements without oil, independent of starch level. Supplementation with high-starch increased the numbers of Entodinium (P < 0.010), and total protozoa (P < 0.010). Furthermore, independently of starch level, the addition of an oil source decreased the population of Dasytricha (P < 0.010), Polyplastron (P < 0.010), and Diploplastron (P = 0.040). Supplementing animals with low-starch (SH) without oil resulted in a higher proportion of Ruminococcus albus (P = 0.012) compared with the other supplements. Moreover, low-starch (SH) supplement, with or without oil, decreased the relative population of Selenomonas ruminantium (P = 0.003). The addition of oil in supplements decreased the number of Fibrobacter succinogenes (P < 0.001), Ruminococcus flavefasciens (P < 0.001), and Archeas (P < 0.001), but increased Anaerovibrio lipolytica populations (P < 0.001). Oil supplement decreased intake, digestibility, acetate production, protozoan populations, and fibrolytic rumen bacteria. The use of soybean hulls without whole soybean supplementation may be effective in increasing the digestibility of CP and R. albus in finishing Nellore steers grazing B. brizantha during the dry season.

      PubDate: 2017-06-19T14:31:55Z
      DOI: 10.1016/j.livsci.2017.06.007
  • Effects of colostrum, and protein and energy supplementation on survival
           and performance of low-birth-weight piglets
    • Authors: L.P. Moreira; M.B. Menegat; G.P. Barros; M.L. Bernardi; I. Wentz; F.P. Bortolozzo
      Abstract: Publication date: Available online 10 June 2017
      Source:Livestock Science
      Author(s): L.P. Moreira, M.B. Menegat, G.P. Barros, M.L. Bernardi, I. Wentz, F.P. Bortolozzo
      The study was conducted to evaluate the effects of the amount of colostrum intake, and an oral protein and energy supplement (OPES) on the concentration of immunoglobulin G (IgG), survival rate, and weight gain of low-birth-weight piglets. Piglets with birth weights ranging from 800 to 1,200g were assigned to 1 of 6 treatments during the first 24h of life as follows. With the sow (WS, n = 30) and WS plus supplement (WSS, n = 30) included piglets suckled by their mothers in conventional farrowing crates, with or without OPES provided, respectively. Feed-deck (FD120, n = 30) and FD plus supplement (FD120S, n = 30) included piglets kept in a feeding deck and fed 120mL (30mL every 6h) of colostrum through an orogastric tube, with or without OPES provided, respectively. The treatments FD200 (n = 29) and FD200S (n = 27) included piglets kept in a feeding deck and fed 200mL (50mL every 6h) of colostrum through an orogastric tube, with or without OPES provided, respectively. The WSS, FD120S, and FD200S piglets received 3 doses (a total of 4mL) of OPES at 0, 6 and 12h of life. The time lapse between the birth and the first colostrum intake or gavage averaged 100.3 ± 47.8min. After the first 24h, they were cross-fostered for suckling to foster mothers of the second to fifth parity. Each litter size was limited to 12 piglets, two of each treatment, and the lactation length was 20.4 ± 0.7 d. For all the analyses, the experimental unit was the individual piglet. The serum concentrations of IgG 24h after birth were greater in FD200 and FD200S than in the WS, FD120, and FD120S, whereas the IgG concentration was similar for WSS and FD200. The greatest weight gain during the first 24h was observed in the WSS, whereas the piglets of FD120 and FD120S lost weight. The average daily gains until weaning, as well as the body weight at 7, 14 and 20 d, were similar among treatments. The piglets from the WSS, FD120S, FD200, and FD200S treatments showed greater pre-weaning survival rates than the piglets in the FD120. The pre-weaning survival rate is improved by the supplementation of 200mL of colostrum. In piglets receiving less colostrum (120mL), the survival rate is increased by the supplementation of the protein and energy supplement.

      PubDate: 2017-06-14T13:06:44Z
      DOI: 10.1016/j.livsci.2017.06.006
  • Effects of rumen-protected pantothenate on ruminal fermentation, microbial
           enzyme activity, cellulolytic bacteria and urinary excretion of purine
           derivatives in growing beef steers
    • Authors: H.Q. Li; Q. Liu; C. Wang; G. Guo; W.J. Huo; S.L Zhang; Y.L. Zhang; C.X. Pei; W.Z. Yang; H. Wang
      Abstract: Publication date: Available online 9 June 2017
      Source:Livestock Science
      Author(s): H.Q. Li, Q. Liu, C. Wang, G. Guo, W.J. Huo, S.L Zhang, Y.L. Zhang, C.X. Pei, W.Z. Yang, H. Wang
      This experiment was to evaluate the effects of rumen-protected pantothenate (RPP) on ruminal fermentation, microbial enzyme activity, bacteria population and urinary excretion of purine derivatives in growing beef steers. Eight ruminally cannulated first-generation crossbred (Blonde d'Aquitaine × Simmental) beef steers, averaging 12 months of age and 363 ± 7kg of body weight (BW), were allocated into a replicated 4 × 4 Latin square design. Four treatments were control, low-RPP (LRPP), medium-RPP (MRPP) and high-RPP (HRPP) with 0, 0.32, 0.48 and 0.64g RPP per kg dietary DM, respectively. Steers were fed a total mixed ration and dietary concentrate to corn silage ratio was 50:50 based on a dry matter (DM) basis. The experiment included four periods and lasted for 96 days, each period contained 14 days of adaptation and 10 days of data collection. Ruminal pH decreased linearly with increasing RPP supplementation and was lower for MRPP than for control. Ruminal total VFA concentration increased linearly with increasing RPP supplementation and was higher for MRPP than for control. The acetate to propionate ratio increased linearly due to the unchanged acetate molar proportion and the tendency towards decreased propionate proportion. Ruminal DM and neutral detergent fibre degradability of corn silage increased quadratically, whereas DM and crude protein degradability of concentrate mix increased linearly with increasing RPP supplementation. Activities of carboxymethyl-cellulase, cellobiase, xylanase and α-amylase increased linearly and was higher for MRPP than for control. Populations of R. albus, R. flavefaciens, F. succinogenes, B. fibrisolvens, P. ruminicola and R. amylophilus increased linearly and quadratically with increasing RPP supplementation. Urinary excretion of purine derivatives increased linearly with increasing RPP supplementation and was higher for HRPP and MRPP than for LRPP and control. The results indicated that dietary supplementary RPP improved ruminal fermentation, in situ ruminal degradation and urinary excretion of purine derivatives by stimulating bacteria growth and microbial enzymes secretion. It is suggested that supplementary RPP regulated bacteria growth and microbial enzymes secretion in a dose-dependent manner. Under the current experimental condition, the appropriate dose of RPP was at 0.48g per dietary DM for growing crossbred beef steer.

      PubDate: 2017-06-10T13:03:33Z
      DOI: 10.1016/j.livsci.2017.06.004
  • The multiple adrenocorticotropic hormone injections significantly alters
           hepatic proteome in growing pigs
    • Authors: Jun Guo; Chao Yin; Gao Shixing; Liu Weifeng; Yanping Huang; Ruqian Zhao; Xiaojing Yang
      Abstract: Publication date: Available online 9 June 2017
      Source:Livestock Science
      Author(s): Jun Guo, Chao Yin, Gao Shixing, Liu Weifeng, Yanping Huang, Ruqian Zhao, Xiaojing Yang
      Currently, the effects of stress on the body metabolism are attracting more and more attentions. To better understand the probable stress-induced metabolic changes, the changes in plasma indices and hepatic proteome were investigated in pigs fitted with jugular venous catheters administered adrenocorticotropic hormone (ACTH), intramuscularly twice daily for 7 days. In particular, plasma hormones, blood cells and biochemical indicators were analyzed. In addition, the hepatic proteome was analyzed by two-dimensional electrophoresis and matrix-assisted laser desorption ionization time of flight mass spectrometry. The results revealed that after the initial ACTH injection, plasma ACTH, cortisol, triiodothyronine and tumor necrosis factor α increased (P ˂ 0.05). Additionally, lactic dehydrogenase activity increased (P ˂ 0.05), and both leukocyte and lymphocyte count decreased (P ˂ 0.05). In comparison, after the ACTH injection for 7 days, hepatic proteomics analysis identified 27 significantly changed proteins and most of these proteins (49%) are involved in metabolism, but plasma indices showed no obvious change. In conclusion, compared with the obvious changes in plasma indices after the initial ACTH injection, the multiple ACTH injections did not change plasma indices, yet the hepatic proteome profile was significantly altered. The results provide useful information for a better understanding of the effects of stress on metabolism.

      PubDate: 2017-06-10T13:03:33Z
      DOI: 10.1016/j.livsci.2017.06.003
  • The effect of post-farrowing ketoprofen on sow feed intake, nursing
           behaviour and piglet performance
    • Authors: Sarah H. Ison; Susan Jarvis; Cheryl J. Ashworth; Kenneth M.D. Rutherford
      Abstract: Publication date: Available online 2 June 2017
      Source:Livestock Science
      Author(s): Sarah H. Ison, Susan Jarvis, Cheryl J. Ashworth, Kenneth M.D. Rutherford
      Farrowing is a critical time for sows and piglets. Poor post-farrowing sow recovery, and piglet mortality represent a welfare concern, as well as an economic loss to the pig industry. Providing a non-steroidal anti-inflammatory drug (NSAID) to the sow post-farrowing may improve sow welfare and productivity and thereby improve health status and welfare of the piglets, which would be of economic benefit to pig producers. This study investigated the production effects of providing the NSAID ketoprofen post-farrowing, to 24 primiparous (gilts) and 32 multiparous (sows) breeding pigs, in a randomised, blinded, placebo-controlled trial. Gilts and sows were allocated to receive ketoprofen (treated) or the equivalent volume of saline (control) by intramuscular injection 1.5hours after the last piglet birth. Data collected included sow feed intake, immune transfer (colostrum and piglet serum immunoglobulin-G (IgG)), nursing behaviour and piglet weight, and mortality. An additional factor in this study was that 13 individuals required additional treatment in the days after farrowing for post-farrowing illness. Therefore, data were analysed using mixed models, including treatment (treated or control), parity group (gilt or sow), and additional treatment (yes or no) as fixed factors. Stepwise binomial logistic regression was used to analyse the association between the experimental factors (treatment, additional treatment, gilt or sow), along with other gilt/sow, litter, and piglet-based measures, with piglet death before weaning. Few treatment effects were seen, with parameters being more affected by whether gilts and sows were treated for illness, or between gilts and sows. The only variable to differ by treatment was suckle grunt duration, which was greater for control compared with treated dams (P = 0.05). Feed consumption was greater for sows compared with gilts on days 6 and 7 post-farrowing, and serum IgG was greater in piglets from sows than gilts (P < 0.05). Feed consumption was reduced in dams needing additional treatment, from days 2–7 post-farrowing, and those developing illness consumed less feed overall (P = 0.004). The best regression model for predicting the odds of a piglet dying before weaning included number born alive (P = 0.03), requiring additional treatment (P = 0.006), being male (P = 0.0005), and pre-farrowing gilt/sow back-fat (P < 0.0001), which increased the log-odds of death, whereas, piglet body weight decreased the log-odds of death (P < 0.0001). This study did not demonstrate clear benefits to ketoprofen, however, high individual variation in piglet mortality, indicates potential for targeted NSAID use.

      PubDate: 2017-06-05T13:01:08Z
      DOI: 10.1016/j.livsci.2017.06.001
  • Effect of season, supplementation and fasting on glycolytic potential and
           activity of AMP-activated protein kinase, glycogen phosphorylase and
           glycogen debranching enzyme in grass-fed steers as determined in
           Longissimus lumborum muscle
    • Authors: A. Apaoblaza; P. Strobel; A. Ramírez-Reveco; N. Jeréz-Timaure; G. Monti; C. Gallo
      Abstract: Publication date: Available online 30 May 2017
      Source:Livestock Science
      Author(s): A. Apaoblaza, P. Strobel, A. Ramírez-Reveco, N. Jeréz-Timaure, G. Monti, C. Gallo
      Forty grass fed beef steers close to slaughter weight (500kg) were used to study the effects of season (one experiment was carried out in autumn and one in summer, same farm, same design), supplementation (grass-fed only=control or flaked corn supplemented=suppl during four weeks before slaughter) and fasting during lairage (0h or 24h fasting). The supplementation with flaked corn started with 0.5kg animal−1day1, fed individually and increasing up to 1% of body weight (approximately 5kg animal−1day1) during the first week; this amount was kept constant for three more weeks.The concentrations of muscle glycogen (MGC), glucose-6-phosphate+glucose (G6P+Gluc) and lactate (LA), glycolytic potential (GPot), activity of AMP-activated protein kinase (AMPK), glycogen phosphorylase (GP) and glycogen debranching enzyme (GDE) were determined in M. Longissimus lumborum (LL);pH and postmortem temperature at 0.5h and 24h were measured. Biopsies from the LL were taken from each steer at the beginning of each experiment (B1), at 0.5h (B2) and 24h postmortem (B3). For each metabolic substrate/product measured in the muscle samples a linear mixed effect model was fitted. GPot, MGC and GP were higher and GDE was lower (P<0.05)in autumn than in summer. Carcass temperature at 0.5h and 24h postmortem was lower in autumn than in summer and non-fasted steers had a lower final carcass temperature than those fasted(P<0.05). Supplementation and no fasting were significant (P<0.05) factors that helped maintaining a higher MGC and GPot in the steers between B1 (on farm biopsy) and B2 (at slaughter); no fasting also helped in increasing GDE activity postmortem (between B2 and B3).The effects of treatments on glycogen reserves and on the activities of the glycolytic enzymes included were not reflected in the ultimate pH of the carcasses, because no differences in terms of mean pH due to any of the factors studied were found (P>0.05). Perhaps other substrates/enzymes that take part in muscle glycolysis/glycogenolysis not included in this study should be analyzed in future studies; considering the high individual variability observed, intrinsic factors of cattle, like genetics, should be taken into consideration.

      PubDate: 2017-06-05T13:01:08Z
      DOI: 10.1016/j.livsci.2017.05.028
  • Feed intake and urinary excretion of nitrogen and purine derivatives in
           pregnant suckler cows fed alternative roughage-based diets
    • Authors: M. Jardstedt; A. Hessle; P. Nørgaard; W. Richardt; E. Nadeau
      Abstract: Publication date: Available online 28 May 2017
      Source:Livestock Science
      Author(s): M. Jardstedt, A. Hessle, P. Nørgaard, W. Richardt, E. Nadeau
      This study compared intake of alternative roughage-based diets and of common late-cut grass silage and related intake to urinary nitrogen (N), urea-N and purine derivative (PD) excretion, where PD is an indicator of rumen microbial crude protein (MCP) synthesis. Total urine was collected from 36 Hereford cows, blocked into three groups based on expected calving date. Cows within calving groups were randomly assigned to one of four roughage diets: common mixed grass silage (MGS), festulolium silage plus urea (FLS), reed canarygrass silage (RCS) and barley straw plus urea and rapeseed meal (BRM). Diet crude protein (CP) content was classified into five fractions (A, B1, B2, B3 and C), based on degradability characteristics. Feed intake and urinary excretion data were analysed by ANOVA in a randomised block design. To further explain the ANOVA results, multiple regression analyses were conducted to study relationships between intakes of total N (g/d); sum of the CP fractions A, B1 and B2 (AB1B2; g/d), most of which is considered rumen-degradable; digestible organic matter (DOMI; kg/d); protein balance in the rumen (g/kg dry matter); and urinary excretion of N, urea-N (g/d) and PD (mmol/d). Urinary N and urea-N excretion was positively related to N intake and was better explained by N intake than intake of AB1B2. Feeding BRM resulted in the lowest N intake and urinary N output (P < 0.001). Cows fed MGS, FLS and RCS had similar N intake, but urinary N and urea-N excretion was significantly higher (P < 0.001) in cows fed RCS, which probably was attributable to the significantly lower DOMI of this diet (P < 0.001). Furthermore, addition of DOMI to N intake in the multiple regression analysis increased the proportion of explained variation in urinary N and urea-N excretion. The MGS and FLS diets stimulated rumen MCP production to a greater extent than the BRM diet, as indicated by the higher urinary output of PD in cows fed the grass silage-based diets (P < 0.001). Diet had no significant effect on urinary PD excretion when expressed per kg DOMI. Overall mean urinary creatinine excretion was 0.197 ± 0.047mmol/kg body weight, with no significant effect of diet. This study showed that intake of both N and DOM need to be assessed when choosing a suitable alternative roughage diet for suckler cows, in order to prevent undesirable losses of urinary N.

      PubDate: 2017-05-30T12:57:12Z
      DOI: 10.1016/j.livsci.2017.05.026
  • Tick resistance genetic parameters and its correlations with production
           traits in Hereford and Braford cattle
    • Authors: Patrícia Biegelmeyer; Claudia Cristina Gulias-Gomes; Vanerlei Mozaquatro Roso; Nelson José Laurino Dionello; Fernando Flores Cardoso
      Abstract: Publication date: Available online 24 May 2017
      Source:Livestock Science
      Author(s): Patrícia Biegelmeyer, Claudia Cristina Gulias-Gomes, Vanerlei Mozaquatro Roso, Nelson José Laurino Dionello, Fernando Flores Cardoso
      Inclusion of cattle genetic resistance to ticks in selection programs represents an auxiliary method in strategic control of this parasite. This study was conducted to estimate genetic parameters for cattle tick resistance measured by tick counting on the inner hind legs region (TCHL) and on one side of body (TCBS) of Hereford and Braford cattle naturally exposed to ticks in southern Brazil. Records of weight gain from birth to weaning (WG), visual scores of conformation, precocity and muscling at weaning (WC, WP and WM, respectively) and at yearling (YC, YP and YM, respectively), weight gain from weaning to yearling (YG) and scrotal circumference (SC) were also analyzed to obtain correlations among all the traits. Heritability estimates obtained by bivariate analysis were TCHL = 0.13 and TCBS = 0.17 and phenotypic correlation between both methods was 0.09 (P<0.05). Repeatability estimate for TCBS was 0.29. Heritability estimates obtained by multivariate analysis were TCBS = 0.19; WG = 0.35; WC = 0.28; WP = 0.23; WM = 0.26; YG = 0.14; YC = 0.18; YP = 0.18; YM = 0.18; and SC = 0.43. No unfavorable genetic correlations among TCBS and growth traits and visual scores at different ages and scrotal circumference have been identified, indicating that simultaneous selection for improving all the traits is feasible.

      PubDate: 2017-05-25T12:50:06Z
      DOI: 10.1016/j.livsci.2017.05.019
  • Nutrient utilization and methane emissions in Murrah buffalo calves fed on
           diets with different methanogenic potential
    • Authors: Sonali Prusty; S.S. Kundu; Vijay Kumar Sharma
      Abstract: Publication date: Available online 24 May 2017
      Source:Livestock Science
      Author(s): Sonali Prusty, S.S. Kundu, Vijay Kumar Sharma
      The objective of the present study was to evaluate the routine ingredients in ruminant feed (grains, agro-industrial byproducts and oilseed cakes) and their combinations for methanogenesis in vitro and to analyze the efficacy of least vs. most methanogenic diet formulations in Murrah buffalo calves. Methane was estimated by in vitro gas production technique. The concentrate mixtures were prepared by combining lower methanogenic ingredients from each category. Alike higher methanogenic ingredients were mixed to formulate concentrate mixtures. Six concentrate mixtures were formulated with metabolizable energy (ME) of 13 MJ/ kg and crude protein (CP) of 20%. Their composition is as follows: C1 (sorghum, rice bran, mustard cake-deoiled (DOMC):: 50, 10, 40), C2 (sorghum, wheat bran, DOMC:: 45, 20, 35), C3 (sorghum, wheat bran, DOMC, cotton seed cake (CSC):: 43, 15, 32, 10), C4 (sorghum, rice bran, DOMC, CSC:: 40, 15, 30, 15), C5 (maize, gram churi, soybean meal (SBM):: 30, 50, 20) and C6 (maize, wheat bran, SBM:: 37, 38, 25). Among them two lower and one higher methanogenic concentrates were chosen and Lucerne fodder was mixed to prepare three rations viz. TLM1 (treatment low methane 1), TLM2 (treatment low methane 2) and THM (treatment high methane). Evaluation of the diets in Murrah buffalo calves (BW, 132 ± 6kg) was done by SF6 tracer technique. There was no significant variation in intake, nutrient digestibility and N retention rate of the rations. Energy loss via methane was higher from THM compared to TLM1 and TLM2 fed group. The loss accounted 13.83% of digestible energy and 16.08% of metabolizable energy of THM ration. Methane loss was lowered by around 10.4% in TLM1 and TLM2 fed group compared to THM. Feed from lower methanogenic ingredients were effective in reducing percentage of dietary energy lost via methane in buffalo calves.

      PubDate: 2017-05-25T12:50:06Z
      DOI: 10.1016/j.livsci.2017.05.023
  • Effect of dietary tannic acid supplementation in corn- or barley-based
           diets on growth performance, intestinal viscosity, litter quality, and
           incidence and severity of footpad dermatitis in broiler chickens
    • Authors: Özcan Cengiz; Bekir Hakan Köksal; Onur Tatlı; Ömer Sevim; Umair Ahsan; Sacit F. Bilgili; Ahmet Gökhan Önol
      Abstract: Publication date: Available online 23 May 2017
      Source:Livestock Science
      Author(s): Özcan Cengiz, Bekir Hakan Köksal, Onur Tatlı, Ömer Sevim, Umair Ahsan, Sacit F. Bilgili, Ahmet Gökhan Önol
      A study was conducted to evaluate the effect of dietary tannic acid and barley supplementation on growth performance, intestinal viscosity, litter quality, and footpad dermatitis (FPD) in broiler chickens. Five hundred forty-four 1-d-old male broiler chicks were randomly assigned to dietary treatments with 8 replicated pens per treatment and 17 broiler chickens pen as a 2 × 2 factorial arrangement of 2 diets (a corn-soybean meal diet or a diet with 30% barley) and tannic acid (0 and 2g / kg) in a completely randomized design. Growth performance, intestinal viscosity, litter quality, and FPD incidence and severity were recorded. The results showed that there was no interaction between diets and tannic acid levels. Barley-based diets reduced (P < 0.05) the body weight (BW) gain at 0 to 42 d, and feed intake at 21 to 42 d and 0 to 42 d. At 28 d of experiment, the viscosity of intestinal contents of anterior and posterior segments was greater (P < 0.05) in broiler chickens fed diets with barley. Similarly, the viscosity of intestinal contents of posterior segment was greater (P < 0.05) at 42 d, in broiler chickens fed barley-based diets. Litter pH, moisture, and NH3 volatilization were increased (P < 0.05) in response to barley-based diets. Barley-based diets increased (P < 0.05) the incidence and severity of FPD lesions in broiler chickens at 14, 28, and 42 d of experiment. Although dietary tannic acid had no effect on performance, intestinal viscosity, and litter quality compared to those fed diets without tannic acid (P > 0.05), it tended to reduce body weight gain (P = 0.05) and increase feed conversion ratio (FCR; P = 0.09) at 0 to 21 d and NH3 volatilization on 28 (P = 0.08) and 42 d (P = 0.07). Dietary tannic acid supplementation prevented the FPD lesion development and reduced (P < 0.05) the total FPD lesions at d 42. Moreover, the severe lesions decreased (P = 0.08) on d 42 in broiler chickens fed tannic acid. In conclusion, barley-based diets may worsen the growth performance and litter quality, and increase the intestinal viscosity that increases the incidence and severity of FPD in broiler chickens. Dietary tannic acid supplementation may not affect the growth performance, intestinal viscosity, and litter quality. However, it may reduce the incidence and severity of FPD in broiler chickens.

      PubDate: 2017-05-25T12:50:06Z
      DOI: 10.1016/j.livsci.2017.05.016
  • Cortisol and DHEA concentrations in the hair of dairy cows managed indoor
           or on pasture
    • Authors: T. Peric; M. Corazzin; A. Romanzin; S. Bovolenta; A. Prandi; M. Montillo; A. Comin
      Abstract: Publication date: Available online 23 May 2017
      Source:Livestock Science
      Author(s): T. Peric, M. Corazzin, A. Romanzin, S. Bovolenta, A. Prandi, M. Montillo, A. Comin
      This study was conducted in order to assess the changes of cortisol and dehydroepiandrosterone (DHEA) concentrations in hair of Italian Simmental dairy cows managed indoor in tie-stall barns or grazing on high mountain pasture. In experiment I, animals were kept in tie-stalls throughout the year (n = 27). In experiment II, animals remained on mountain pastures during summer (from 20th June to 20th September) and then kept indoors in tie-stalls for the rest of the year (n = 18). At the end of July, following vertical transhumance, dairy cows were moved to a pasture located at a higher altitude. In the two studies, hair samples, obtained using clippers from the animal's forehead, were collected on the 20th June (P1), 20th July (P2), 20th August (P3), 20th September (P4) and 20th October (P5) and analysed for cortisol and DHEA. In experiment I, DHEA concentration was unaffected by sampling time (P > 0.05), whereas, cortisol/DHEA ratio was similar between P1 and P2 (P > 0.05) and then increased during the experimental period reaching the highest value at P5 (P < 0.05). In experiment II, dairy cows had higher concentration of DHEA during grazing compared to cows kept indoors (P < 0.05), conversely cortisol/DHEA ratio decreased from P1 to P2 (P < 0.05), remained constant from P2 to P3 (P > 0.05) and then increased from P3 to P4 (P < 0.05), the highest value was recorded at P5. In conclusion, cortisol and DHEA concentrations and their ratio measured in the hair of dairy cows can be useful to evaluate the allostatic load in animals managed indoor in tie-stall barn or grazing on mountain pasture.

      PubDate: 2017-05-25T12:50:06Z
      DOI: 10.1016/j.livsci.2017.05.020
  • Multivariate analysis of muscle fiber characteristics, intramuscular fat
    • Authors: Jin-Yeon Jeong; Tae-Chul Jeong; Han-Sul Yang; Gap-Don Kim
      Abstract: Publication date: Available online 19 May 2017
      Source:Livestock Science
      Author(s): Jin-Yeon Jeong, Tae-Chul Jeong, Han-Sul Yang, Gap-Don Kim
      Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied to investigate the relationship between muscle fiber characteristics, intramuscular fat (IMF) content and fatty acid composition in the porcine longissimus thoracis muscle. The cluster with the highest IMF content had the highest saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and muscle fiber characteristics of type I (P<0.05). The polyunsaturated fatty acid (PUFA) showed positive correlations with the cross-sectional area and relative area of type IIB and the relative number of fiber type IIA in the HCA and PCA results. Therefore, porcine muscle with a high density, relative area and cross-sectional area of type I was found to have a high content of IMF, SFAs and MUFAs, whereas in the case of a large cross-sectional area and relative area of type IIB, the proportion of PUFAs increased. These findings lead to a better understand of different fatty acid compositions in skeletal muscles which have different metabolic and contractile properties.

      PubDate: 2017-05-20T12:34:56Z
      DOI: 10.1016/j.livsci.2017.05.015
  • Implementation of machine vision for detecting behaviour of cattle and
    • Authors: Abozar Nasirahmadi; Sandra A. Edwards; Barbara Sturm
      Abstract: Publication date: Available online 19 May 2017
      Source:Livestock Science
      Author(s): Abozar Nasirahmadi, Sandra A. Edwards, Barbara Sturm
      Livestock production to provide food for a growing world population, with increasing demand for meat and milk products, has led to a rapid growth in the scale of cattle and pig enterprises globally. However, consumers and the wider society are also increasingly concerned about the welfare, health and living conditions of farm animals. Awareness of animal needs underpins new production standards for animal health and welfare. Pig and cattle behaviour can provide information about their barn environmental situation, food and water adequacy, health, welfare and production efficiency. Real-time scoring of cattle and pig behaviours is challenging, but the increasing availability and sophistication of technology makes automated monitoring of animal behaviour practicable. Machine vision techniques, as novel technologies, can provide an automated, non-contact, non-stress and cost-effective way to achieve animal behaviour monitoring requirements. This review describes the state of the art in 3D imaging systems (i.e. depth sensor and time of flight cameras) along with 2D cameras for effectively identifying livestock behaviours, and presents automated approaches for monitoring and investigation of cattle and pig feeding, drinking, lying, locomotion, aggressive and reproductive behaviours. The performance of developed systems is reviewed in terms of sensitivity, specificity, accuracy, error rate and precision. These technologies can support the farmer by monitoring normal behaviours and early detection of abnormal behaviours in large scale enterprises.

      PubDate: 2017-05-20T12:34:56Z
      DOI: 10.1016/j.livsci.2017.05.014
  • Genome-wide association study for sow lifetime productivity related traits
           in a Landrace purebred population
    • Authors: J.H. Kang; E.A. Lee; S.H. Lee; S.H. Kim; D.H. Lee; K.C. Hong; H.B. Park
      Abstract: Publication date: Available online 19 May 2017
      Source:Livestock Science
      Author(s): J.H. Kang, E.A. Lee, S.H. Lee, S.H. Kim, D.H. Lee, K.C. Hong, H.B. Park
      Improvement of sow lifetime productivity (SLP) is expected to increase farm performance and profitability. Many genes and environmental factors influence these complex traits. To identify quantitative trait loci and positional candidate genes for SLP-related traits, we performed a genome-wide association study (GWAS) using 656 Landrace purebred pigs from a commercial breeding stock farm. All sows in the study population were genotyped with the Illumina Porcine SNP60 BeadChip, and GWAS analyzed by linear mixed-effects model based association analysis using the GCTA program. Five genome-wide suggestive single nucleotide polymorphism markers were identified for the lifetime total number of born piglets and final parity. All five of these markers were highly associated with other SLP-related traits, and all these markers were located within or near one particular gene, MEGF11 (multiple epidermal growth factor-like domains protein 11), on chromosome 1. This new positional candidate gene could contribute to increased sow lifetime productivity after the validation in other populations.

      PubDate: 2017-05-20T12:34:56Z
      DOI: 10.1016/j.livsci.2017.05.013
  • The effect of earthworm (Eisenia foetida) meal with vermi-humus on growth
           performance, hematology, immunity, intestinal microflora, carcass
           characteristics, and meat quality of broiler chickens
    • Authors: Z. Bahadori; L. Esmaielzadeh; M.A.K. Torshizi; A. Seidavi; J. Olivares; S. Rojas; A.Z.M. Salem; S. Lopez
      Abstract: Publication date: Available online 17 May 2017
      Source:Livestock Science
      Author(s): Z. Bahadori, L. Esmaielzadeh, M.A.K. Torshizi, A. Seidavi, J. Olivares, S. Rojas, A.Z.M. Salem, S. Lopez
      The present investigation was aimed to evaluate the effect of varied amount of earthworm meal (EW) and vermi-humus (VH) on the growth performance of broiler chickens. Three hundred 1-d-old broiler chickens were assigned to 5 starter treatments with 5 pens per treatment, and 12 broiler chickens per pen in a completely randomized design from d 0 to 14 of the study. Dietary treatments were [per kilogram dry matter (DM)]: control (0g EW and 0g VH/kg of DM), and the diets containing 10g VH/kg of DM supplemented with 0, 10, 20, or 30g EW/kg of DM. At the end of the study (d 42), 1 representative broiler chicken per pen, close to the average body weight, was selected for blood sampling using a sterile needle and heparinized vacuum tube. The outcomes of the study depicted the greater overall feed intake value in broiler chicken fed the control diet than those fed the diets containing VH or EW or both, and it decreased linearly and quadratically (P<0.05) as the amount of EW supplementation increased. The overall body weight gain for the chickens was increased with increase in the supplementation of EW (linear, P=0.3; quadratic P=0.4). On the other hand, overall feed conversation ratio was slightly greater (P=0.02) in broiler chickens fed the control diet, and it decreased linearly (P=0.03) as dietary EW supplementation increased. Additionally, the serum total protein, albumin, Ca, and P concentrations were lower in broiler chickens fed the control diet, and those variables increased linearly (P<0.05) as dietary EW increased. In like manner, humoral immune response (except heterophil/lymphocyte ratio) and relative weights of immune organs were lower in broiler chickens fed the control diet. Remarkable differences were observed between carcass and ileum characteristics of broiler chickens under treatments. Varied concentrations of EW showed increased total counts of lactic acid bacteria (linear, P<0.05; quadratic, P=0.3) and reduced population of pathogenic intestinal microflora (linear, P<0.05; quadratic, P>0.05). Similarly, the meat quality of broiler chicken was markedly affected linearly (P<0.05) by the supplementation of increased dietary EW. Briefly, diets containing 30g EW/kg of DM can positively affect the growth performance of broiler chickens and produce meat with better characteristics.

      PubDate: 2017-05-20T12:34:56Z
      DOI: 10.1016/j.livsci.2017.05.010
  • Evaluation of performance models for farm-specific optimization of pig
    • Authors: Frederik Leen; Alice Van den broeke; Bart Ampe; Ludwig Lauwers; Jef Van meensel; Sam Millet
      Abstract: Publication date: Available online 17 May 2017
      Source:Livestock Science
      Author(s): Frederik Leen, Alice Van den broeke, Bart Ampe, Ludwig Lauwers, Jef Van meensel, Sam Millet
      Farm-specific optimization of pig production can be supported with a production function mechanistically derived from dynamic growth and feed intake information, hereafter called performance curves. Production–theoretical optimization requires, first, an accurate description of underlying processes and, second, possibilities for calibrations with available on-farm data. The objective is to evaluate accuracy and calibration requirements of seven models: the Gompertz, monomolecular, Richards and Generalized Michaelis-Menten (GMM) model for growth and the cumulative feed intake and weight (CFIW), Bridges and Giesen models for both growth and feed intake. Evaluation is done with data from four trials with four sexes of a Piétrain x hybrid sow cross: boars, barrows, gilts and GnRH-vaccinated boars. Accuracy was evaluated with Root Mean Squared Errors (RMSE) of predictions versus observations and F-tests for differences in goodness-of-fit to discriminate between models. Calibration possibilities were evaluated through fitting the models through limited data. The Giesen, Bridges and GMM model, describing sigmoidal growth patterns, showed the highest accuracy. In terms of calibration possibilities, the Bridges model slightly outperformed the other. The Giesen model is accurate for describing feed intake of boars, barrows, gilts. GnRH-vaccinated animals showed unstable variance with increasing age of the animal, which could only partially been solved with extensions to the Bridges and Giesen model. The research showed that dynamic growth and feed intake curves can be reasonably estimated from limited on-farm collectable data and generic functional forms, and as such account for farm specificity in production-theoretical economic optimization.

      PubDate: 2017-05-20T12:34:56Z
      DOI: 10.1016/j.livsci.2017.05.006
  • The effect of mixing piglets after weaning on the occurrence of
           tail-biting during rearing
    • Authors: Christina Veit; Kathrin Büttner; Imke Traulsen; Marvin Gertz; Mario Hasler; Onno Burfeind; Elisabeth grosse Beilage; Joachim Krieter
      Abstract: Publication date: Available online 8 May 2017
      Source:Livestock Science
      Author(s): Christina Veit, Kathrin Büttner, Imke Traulsen, Marvin Gertz, Mario Hasler, Onno Burfeind, Elisabeth grosse Beilage, Joachim Krieter
      The aim of this study was to investigate the effects on tail-biting during rearing of housing piglets of the same litter compared to piglets from different litters. The treatments “litter-wise” (LW, n = 240) and “mixed litters” (ML, n = 238) were housed in five identical units. Each tail was scored regarding tail lesions and tail losses once per week with a four-point score (0 = no damage/original length to 3 = severe damage/total loss). The effect of week after weaning had highly significant influences on tail lesions (p < 0.001). Tail-biting started in the second week after weaning, with an increasing severity during rearing. First tail losses were observed in the fourth week after weaning. The batch and the interaction between treatment and batch had highly significant influences on tail losses at the end of rearing (p < 0.001). Depending on batch, piglets in the LW or ML treatment were more affected by tail-biting.

      PubDate: 2017-05-10T14:55:00Z
      DOI: 10.1016/j.livsci.2017.05.003
  • Energy and lysine requirements and balances of sows during transition and
           lactation: A factorial approach
    • Authors: Takele Feyera; Peter Kappel Theil
      Abstract: Publication date: Available online 3 May 2017
      Source:Livestock Science
      Author(s): Takele Feyera, Peter Kappel Theil
      This study aimed to quantify daily requirements for metabolizable energy (ME) and standard ileal digestible (SID) lysine in late gestating and lactating sows using a factorial approach. Metabolizable energy and SID lysine required for fetal and mammary growth, colostrum and milk production, uterine components (including uterus wall, placenta and membrane fluids) and maintenance were estimated. It was estimated that maintenance, additional heat loss, colostrum production, fetal growth, mammary growth and uterine components accounted for 66.8, 19.3, 7.2, 5.0, 1.3 and 0.5% of total ME requirements, respectively, in the last 12 days of gestation. Oxidation/transamination, fetal growth, mammary growth, colostrum production, maintenance and uterine components were estimated to account for 29.5, 22.7, 16.8, 16.1, 10.4 and 4.5% of total SID lysine requirements, respectively, in the last 12 days of gestation. After parturition, ME and SID lysine requirements increased daily until peak lactation (day 17). At peak lactation, 95% and 72% of total required SID lysine and ME, respectively, were associated with milk production (including oxidation). Relative to day 104 of gestation, ME and SID lysine requirements increased by 60 and 149% at day 115 of gestation, and by 228%, and 338% at peak lactation, respectively. A dietary SID lysine: ME ratio of 0.55 was estimated as the ideal ratio to optimize milk production at peak lactation. It was estimated that the regressing uterus released about 29.9g SID lysine and 14.3 MJ ME into the endogenous plasma pool during lactation. It was concluded that dramatic changes in energy and lysine requirements and balances occur during transition and lactation; that sows with high milk yield and /or low live weight require high SID lysine: ME ratio and that it would be beneficial to feed sows with two components at each meal to match the daily requirements for maintenance and production.

      PubDate: 2017-05-06T14:48:07Z
      DOI: 10.1016/j.livsci.2017.05.001
  • Whole blood optimization and genetic association of ex vivo TNF-α
           responsiveness to killed E. coli in Danish Holstein cows
    • Authors: M. Khatun; H.B.H. Jørgensen; A. Ehsani; M.S. Lund; G. Sahana; P. Sørensen; C.M. Røntved
      Abstract: Publication date: Available online 29 April 2017
      Source:Livestock Science
      Author(s): M. Khatun, H.B.H. Jørgensen, A. Ehsani, M.S. Lund, G. Sahana, P. Sørensen, C.M. Røntved
      Whole blood stimulation assay (WBA) has been widely used to study production of the pro-inflammatory cytokine, tumor necrosis factor-alpha (TNF-α) and is considered a relatively good predictor for the in vivo release of TNF-α during endotoximia in dairy cattle. However, it requires a standardized and optimized dose of lipopolysaccharides (LPS) to simulate the in vivo cytokine response during WBA when using killed bacteria. Moreover, if an association between genome (e. g., Quantitative trait loci) and ex vivo TNF-α responsiveness can be established; it helps to reduce mastitis in dairy cattle using selective breeding. Three experiment scenarios for pathogen dose, stimulation time and estimation of genetic variables effect in ex vivo TNF-α production were carried out to investigate differences of TNF-α responsiveness in early lactation in 4, 38 and 40 Danish Holstein-Friesian dairy cows respectively. Statistical analysis done using ANOVA, t.test and lm functions in R software. Results showed that, ex vivo TNF-α response to E. coli is dose and time dependent and a dose of 2.5×106 CFU/mL for 3.5h is optimal for observing TNF-a response after ex vivo stimulation. Relatively consistent inter-individual cow differences in the TNF-α response ex vivo were observed from week 3 to week 8. No statistically significant association were found between the ex vivo TNF-α responsiveness and the two E. coli associated mastitis QTLs which may be due to the low number of animals (n=) in the study.

      PubDate: 2017-04-30T14:34:58Z
      DOI: 10.1016/j.livsci.2017.04.014
  • Dietary chitosan improves nitrogen use and feed conversion in diets for
           mid-lactation dairy cows
    • Authors: Tiago A. Del Valle; Pablo G. de Paiva; Elmeson F. de Jesus; Gustavo F. de Almeida; Filipe Zanferari; Artur G.B.V.B. Costa; Ives C.S. Bueno; Francisco P. Rennó
      Abstract: Publication date: Available online 27 April 2017
      Source:Livestock Science
      Author(s): Tiago A. Del Valle, Pablo G. de Paiva, Elmeson F. de Jesus, Gustavo F. de Almeida, Filipe Zanferari, Artur G.B.V.B. Costa, Ives C.S. Bueno, Francisco P. Rennó
      Feed additives and fat sources have been used to meet high productive dairy cow energy requirements. This study aimed to evaluate dietary chitosan and soybean oil effects on mid-lactation dairy cow intake, digestibility, metabolism and productive performance. Twenty-four Holstein cows (134.7 ± 53.1 days in milk, 36.14 ± 5.32kg/day of milk yield, and 581.2 ± 73.6kg of body weight, Mean ± SD) were used in a replicated 4 × 4 Latin square design with 21-d periods, with 14 d of adaptation and 7 d for data collection. The treatment arrangement was a 2 × 2 factorial design with two levels of chitosan (0 and 4g/kg of dietary dry matter - DM) and two levels of soybean oil (0 and 33g/kg of dietary DM). Chitosan decreased intake only in diets without oil (P<0.05). Regardless of fat addition, chitosan increased DM and CP digestibility (P<0.05). Soybean oil and chitosan increased total serum cholesterol (P<0.05). Chitosan diet had higher urea plasma concentration than control diet (CON) (P<0.05). Over all, soybean oil increased propionate and decreased acetate ruminal molar proportion, and therefore decreased acetate:propionate ratio (P<0.05). Chitosan decreased milk yield, nitrogen use and feed conversion efficiencies in oil-diets (P<0.05). Soybean oil decreased short and medium milk fatty acids concentration (P<0.05). Chitosan had no effect on long-chain milk fatty acids in diets with soybean oil (P>0.05). However, in free oil-diets, chitosan increased milk polyunsaturated fatty acids concentration, nitrogen and energy efficiency. Chitosan addition in free-fat diets improved feed efficiency, increased milk unsaturated fatty acids concentration and association with soybean oil negatively affect animal performance.

      PubDate: 2017-04-30T14:34:58Z
      DOI: 10.1016/j.livsci.2017.04.003
  • Genetic characterization of Czech local rabbit breeds using microsatellite
    • Authors: Martina Jochová; Karel Novák; Tomáš Kott; Zdeněk Volek; Ivan Majzlík; Eva Tůmová
      Abstract: Publication date: Available online 26 April 2017
      Source:Livestock Science
      Author(s): Martina Jochová, Karel Novák, Tomáš Kott, Zdeněk Volek, Ivan Majzlík, Eva Tůmová
      The genetic diversity and genetic relatedness of seven indigenous Czech rabbit breeds included in the National Program of Conservation and Utilization of Genetic Resources was evaluated. The set was completed with a modern strain hybrid Hyplus 19 × 59 for comparison. Sixteen microsatellite loci compiled from published sources were multiplexed by 3 or 4 in order to rationalize the reactions and capillary electrophoresis. High level of diversity was demonstrated in all breeds, as expressed by polymorphism information content of the markers and allelic richness, in spite of the limited populations of most of the traditional breeds. On the other hand, the ubiquitous presence of private alleles and substantial genetic distances among the breeds indicated considerable distinctness of all the breeds at the molecular level. The microsatellite profiles were sufficiently characteristic to allow breed assignment of most individuals. The differences among breeds allowed for building an interpretable similarity dendrogram, although without statistical evidence for the hierarchical structure of the multi-breed population. Clustering at the individual animal level and probabilistic assignment of animals to the newly delimited groups consistently revealed distinct subpopulations in two breeds. The degree of inbreeding as a threat to the conservation program was evaluated with the heterozygosity coefficient and the subpopulation inbreeding coefficient F IS . While heterozygosity corresponded to the panel of European breeds, it remained lower than the values reported for wild and other domestic populations. In conclusion, the conserved rabbit breeds can serve as a reservoir of genetic variants for future breeding despite low-numbered living populations.

      PubDate: 2017-04-30T14:34:58Z
      DOI: 10.1016/j.livsci.2017.03.025
  • Associations between EP-like lesions and pleuritis and post trimming
           carcass weights of finishing pigs in England
    • Authors: V.R. Brewster; H.C. Maiti; A.W. Tucker; A. Nevel
      Abstract: Publication date: Available online 23 April 2017
      Source:Livestock Science
      Author(s): V.R. Brewster, H.C. Maiti, A.W. Tucker, A. Nevel
      Herd health slaughter checks regularly identify enzootic pneumonia-like (EP-like) lesions and pleuritis. The aim of this paper is to determine the associations between these lesions and post-trimming carcass weight. Data were collected on the presence/ absence and severity of EP-like lesions and presence/ absence of pleuritis from pigs at the abattoir. Linear mixed models identified a significant association between an increase in EP-like lesion severity and a decrease in post-trimming carcass weight (P = 0.006) at the individual level. Each categorical increase in EP-like lesion severity (5 points step) was associated with a 0.37kg reduction in post-trimming carcass weight. The presence of EP-like lesions in individual pigs, irrespective of severity (P = 0.034) and the presence of pleuritis (P = 0.038) were significantly associated with a reduction in post-trimming carcass weight of 1.26kg and 1.25kg respectively. The results confirm that the presence of these lesions at slaughter are associated with a significant decrease in production performance which can result in substantial economic implications for producers.

      PubDate: 2017-04-30T14:34:58Z
      DOI: 10.1016/j.livsci.2017.04.012
  • Effect of gelatin supplementation on growth performance and blood
           metabolites of broiler chickens fed diets varying in crude protein
    • Authors: Asadi Kermani; M.H. Shahir Baradaran
      Abstract: Publication date: Available online 13 April 2017
      Source:Livestock Science
      Author(s): Z. Asadi Kermani, M.H. Shahir, N. Baradaran
      An experiment was conducted to investigate the effects of gelatin inclusion on growth performance, blood metabolites and carcass characteristics of broiler chickens fed diets varying in crude protein (CP) concentration in a 42-d study. Four concentrations of gelatin (0, 30, 60, and 90g/kg) and 2 concentrations of CP in the starter (220 and 200g/kg) and grower (195 and 182g/kg) periods were evaluated in a 2 × 4 factorial arrangement of treatments. Each diet was fed to 5 replicate pens of 15 male broiler chickens (Ross 308) from d 0 to 42. Digestibility coefficients of amino acid (AA) of gelatin were in the range of 0.90 to 0.95. Gly, Pro, Ala, and Glu were the major AA in gelatin. There were interactions between dietary CP content and gelatin concentration for feed intake (FI; P = 0.016), body weight gain (BWG; P < 0.001) and feed conversion ratio (FCR; P < 0.001) during the starter (d 0 to 21), grower (d 21 to 42), and the overall experiment period (d 0 to 42). In the low CP diets, gelatin inclusion had a greater negative effect on BWG and FCR compared with those fed the normal CP diets over the course of the experiment (gelatin × CP, P < 0.001). The contrasts showed that the increase in dietary gelatin content decreased BWG and FI, whereas FCR increased with higher dietary gelatin content from d 0 to 42. The CP × gelatin interactions showed that gelatin addition to the low CP diets increased plasma concentrations of glucose (gelatin × CP, P < 0.01) and uric acid (gelatin × CP, P < 0.001), and decreased N retention (gelatin × CP, P < 0.001) to a greater extent than was the case for the normal CP diets at d 42. The CP × gelatin interactions indicated that gelatin inclusion in the low CP diets decreased carcass yield (gelatin × CP, P < 0.01) and abdominal fat (gelatin × CP, P < 0.001), and increased heart weight (gelatin × CP, P < 0.01) to a greater extent than was the case for the normal CP diets. The present findings showed that gelatin inclusion had a greater negative effect on growth performance and carcass yield in broiler chickens that received the low CP diets compared with those fed the normal CP diet over the course of the study. Also, increasing dietary gelatin content depressed growth rate and N retention.

      PubDate: 2017-04-16T06:23:15Z
  • Bayesian analysis of pig growth curves combining pedigree and genomic
    • Authors: Sirlene Fernandes Lázaro; Noelia Ibáñez-Escriche; Luis Varona; Fabyano Fonseca e Silva; Lais Costa Brito; Simone Eliza Facioni Guimarães; Paulo Sávio Lopes
      Abstract: Publication date: Available online 4 April 2017
      Source:Livestock Science
      Author(s): Sirlene Fernandes Lázaro, Noelia Ibáñez-Escriche, Luis Varona, Fabyano Fonseca e Silva, Lais Costa Brito, Simone Eliza Facioni Guimarães, Paulo Sávio Lopes
      We proposed a genome association study for pig growth curves based on Bayesian hierarchical framework considering different sets of SNP markers and pedigree. Additionally, we aimed also to identify possible chromosome regions affecting the growth curve parameters using empirical weight-age data from an outbred F2 (Brazilian Piau vs commercial) pig population. Under the proposed hierarchical approach, individual growth trajectories were modeled by the nonlinear Gompertz function, so that the parameter estimates were considered to be affected by additive polygenic, systematic and SNP markers effects. The model assuming jointly pedigree and SNP markers presented the best fit based on Deviance Information Criterion. Heritability estimates ranged from 0.53 to 0.56 and from 0.55 to 0.57, respectively for the parameters mature weight (a) and maturing rate (k). Additionally, we found high and positive genetic correlation (0.78) between “a” and "k". The percentages of the genetic variances explained by each SNP allowed identifying the most relevant chromosome regions for each phenotype (growth curve parameters). The majority of these regions were closed to QTL regions previously reported for growth traits. However, we identified three relevant SNPs (55840514bp at SSC17, 55814469 at SSC17 and 76475804 at SSC X) affecting "a" and "k" simultaneously, and three SNPs affecting only "a" (292758bp at SSC1, 67319bp at SSC8 and 50290193bp at SSC17), that are located in regions not previously described as QTL for growth traits in pigs.

      PubDate: 2017-04-09T10:33:27Z
      DOI: 10.1016/j.livsci.2017.03.024
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