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AGRICULTURE (569 journals)

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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  [3123 journals]
  • The effect of dairy cow breed on milk production, cow traffic and milking
           characteristics in a pasture-based automatic milking system
    • Authors: J. Shortall; C. Foley; R.D. Sleator; B. O’Brien
      Pages: 1 - 7
      Abstract: Publication date: March 2018
      Source:Livestock Science, Volume 209
      Author(s): J. Shortall, C. Foley, R.D. Sleator, B. O’Brien
      Despite the increasing frequency of integrated automatic milking (AM) and pasture-based systems, there is limited knowledge available on the suitability of different dairy cow breeds to these systems. Thus, the objective of this experiment was to establish the performance of three breeds in a pasture-based AM system with respect to milk production, cow traffic and milking characteristics. The breeds examined were Holstein Friesian (HF), Jersey x HF (JEX) and Norwegian Red x HF (NRX), all of which have been previously identified as being compatible with conventional milking pasture-based systems. The experiment was conducted in mid-lactation and variables measured included milking frequency, -interval, -outcome and -characteristics, milk yield/milking and per day, wait time/visit and per day, return time/visit and the daily distribution of milking events. Data were statistically analysed using least squares means mixed procedure models, while the proportion of different milking events were analysed using the logistics procedure. While there were no significant differences between breeds for milking frequency, or milk production, significant differences did exist for proportion of successful and failed milkings events, with NRX cows recording the highest and lowest proportions, respectively. JEX also recorded a significantly shorter dead time/quarter at 17.6s/milking compared to the HF and NRX breeds at 28.5 and 27.7s/milking, respectively. Significant differences also existed with regard to cow traffic, with the NRX breed returning from pasture more quickly and waiting a shorter time both per visit and per day in the pre-milking yard. The distribution of milking events differed between the breeds examined, with the JEX cows recording less milkings in the hour after the pre-selection gate changes of 0000h and 1600h. JEX also recorded a significantly greater proportion of milkings than the NRX and HF cows during the hours at which the lowest proportion of total milking events were recorded (0400–0600h). For the optimisation of the AM system it is important to have an even distribution of milkings throughout the day. Based on the evidence from the current experiment, this may be best achieved by a mixed breed herd rather than a single breed herd. However, the performance of the examined breeds should also be analysed in the context of the whole AM farm system, over an entire lactation, taking into consideration the range of variables that contribute to a profitable farm system.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.002
      Issue No: Vol. 209 (2018)
       
  • Dietary arginine supplementation enhances the growth performance and
           immune status of broiler chickens
    • Authors: Y.Q. Xu; Y.W. Guo; B.L. Shi; S.M. Yan; X.Y. Guo
      Pages: 8 - 13
      Abstract: Publication date: March 2018
      Source:Livestock Science, Volume 209
      Author(s): Y.Q. Xu, Y.W. Guo, B.L. Shi, S.M. Yan, X.Y. Guo
      This experiment was conducted to investigate the effects of dietary Arg on growth performance and immunity in broiler chickens. Three hundred 1-d-old broiler chickens were divided into 5 treatments with 6 cages and 10 chickens per cage. The broiler chickens in the 5 treatments were fed with the basal diet (Arg-deficient diet, 8.6% Arg in diet from 0 to 21 d and 6.8% Arg in diet from 21 to 42 d) supplemented with 0%, 0.45%, 0.90%, 1.35%, and 1.80% Arg, respectively. The effects of dietary Arg on performance and immune status were assessed. The results showed that, with increasing of dietary Arg content, body weight was increased quadratically on d 21 (P < 0.01) and 42 (P < 0.01). The daily weight gain (P < 0.01) and feed conversion (P < 0.05) were improved quadratically during the entire period. In addition, with increasing of dietary Arg content, serum concentrations of growth hormone (P < 0.01), insulin-like growth factors-1 (P < 0.01), insulin (P < 0.01), IgA (P < 0.01), and IFN-γ (P < 0.01), as well as thymus weight (P < 0.05) of broiler chickens, were improved quadratically on d 21; and lymphocyte proliferation (P < 0.01), the antibody titers to newcastle disease (linear, P < 0.01; quadratic, P < 0.01), and serum IgM concentration (P < 0.05) were increased linearly or quadratically on d 42. The results indicated that incorporating Arg in excess of the 1994 NRC requirement improves the growth and immunity of broiler chickens.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.001
      Issue No: Vol. 209 (2018)
       
  • Expression of progesterone receptor and progesterone-induced blocking
           factor in the spleen during early pregnancy in ewes
    • Authors: Ling Yang; Runqing Guo; Xiaolei Yao; Jinkun Yan; Ying Bai; Leying Zhang
      Pages: 14 - 19
      Abstract: Publication date: March 2018
      Source:Livestock Science, Volume 209
      Author(s): Ling Yang, Runqing Guo, Xiaolei Yao, Jinkun Yan, Ying Bai, Leying Zhang
      The spleen plays a key role in immune regulation. Progesterone (P4) exhibits different immunological effects through binding to different types of receptor. In the present study, splenic samples were obtained at day 16 of non-pregnancy and days 13, 16, and 25 of pregnancy to study the expression of P4 receptor (PGR) and P4-induced blocking factor (PIBF) in ewes through quantitative real-time PCR, Western blot and immunohistochemistry analysis. Our results showed that the relative expression levels of PGR and PIBF mRNA increased from day 13–16 in pregnant ewes, but decreased from day 16–25, and the 26kDa isoform of PGR and the 22kDa variant of PIBF were down-regulated in the spleens at day 25 of pregnancy compared with expression at day 16 of the oestrous cycle and days 13 and 16 of pregnancy. The immunohistochemistry test results confirmed that PGR and PIBF proteins were localized in the cytoplasm of cells in the capsule, trabeculae and splenic cords. This paper reports for the first time that the 26kDa isoform of PGR and the 22kDa variant of PIBF were down-regulated during early pregnancy, which may be essential for normal pregnancy in ewes.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.004
      Issue No: Vol. 209 (2018)
       
  • Effects of abomasal supplementation of quercetin on performance,
           inflammatory cytokines, and matrix metalloproteinase genes expression in
           goats fed a high-grain diet
    • Authors: C. Guo; H. Li; D. Sun; J. Liu; S. Mao
      Pages: 20 - 24
      Abstract: Publication date: March 2018
      Source:Livestock Science, Volume 209
      Author(s): C. Guo, H. Li, D. Sun, J. Liu, S. Mao
      Ten abomasally fistulated male goats fed twice daily at a constant rate of 4% of body weight were used to investigate the effects of abomasal supplementation of quercetin on rumen fermentation and the mRNA expression of inflammatory cytokines in the rumen epithelium, liver and hoof tissues, and the expression of matrix metalloproteinase genes in hoof tissues. The goats were placed in individual pens (1.2 × 1.2m) with free access to water and randomly divided to two groups: one group fed an high grain diet (HG) without quercetin (control, n = 5) and the other group fed HG and treated with quercetin (treatment, n = 5) for 4 weeks. Results showed that abomasal supplementation of quercetin increased the average daily feed intake (P < 0.001) and body weight (P < 0.01). The concentration of free lipopolysaccharide (LPS) (P < 0.05) in rumen fluid was higher in goats supplemented with quercetin compared with the control group. Quercetin supplementation did not affect the mRNA expression of IL-1β, IL-6, TNF-α, IL-10, IL-12, and IFN-γ in the ruminal epithelial tissue (P > 0.05). Quercetin supplementation decreased the IL-1β mRNA expression (P < 0.05) and increased IL-10 mRNA expression (P < 0.05) in the liver tissues. Quercetin supplementation downregulated the mRNA expression of IL-1β (P < 0.01) and tended to downregulate the TNF-α mRNA expression (P > 0.05) in the hoof. Quercetin supplementation also lowered the mRNA expression levels of MMP-2 (P < 0.05) and MMP-9 (P < 0.01) in the hoof tissue. In conclusion, abomasal supplementation of quercetin improved the performance, decreased the mRNA expressions of inflammatory cytokines in the liver and hoof tissues, and reduced the risk of laminitis in goats.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.003
      Issue No: Vol. 209 (2018)
       
  • Effect of substituting barley with glycerol as energy feed on feed intake,
           milk production and milk quality in dairy cows in mid or late lactation
    • Authors: Charlotte Gaillard; Martin Tang Sørensen; Mogens Vestergaard; Martin Riis Weisbjerg; Mette Krogh Larsen; Henrik Martinussen; Ulla Kidmose; Jakob Sehested
      Pages: 25 - 31
      Abstract: Publication date: March 2018
      Source:Livestock Science, Volume 209
      Author(s): Charlotte Gaillard, Martin Tang Sørensen, Mogens Vestergaard, Martin Riis Weisbjerg, Mette Krogh Larsen, Henrik Martinussen, Ulla Kidmose, Jakob Sehested
      The experiment reported in this research paper aimed to determine the level at which glycerol can substitute barley in grass-clover silage-based ration for dairy cows in mid or late lactation, without affecting milk production, milk composition, milk free fatty acid (FFA) profile, and milk sensory quality. Forty Holstein cows were used in a 4 × 4 Latin square experimental design. Crude glycerol substituted barley in the partially mixed ration (PMR) of the cows at inclusion levels of 0% (Gly0), 6% (Gly6), 12% (Gly12), and 18% (Gly18) of dietary dry matter (DM). Individual milk production, feed intake, and milking frequency were recorded daily, while milk composition and milk FA daily were analyzed weekly. Milk sensory analysis was performed on fresh and 7 d stored samples for the four diets. The PMR intake increased almost 1kg from Gly0 to Gly12, and decreased by approximately 1kg from Gly12 to Gly18. Concentrate intake at the automated milking unit tended to decrease by half a kg from Gly0 to Gly6. Milk yield decreased linearly with increasing proportions of glycerol in the diet while fat and protein contents in milk increased. This resulted in a quadratic effect of dietary glycerol level on ECM yield, with maximum yield with Gly6 and the lowest yield with Gly18. Protein and lactose yields decreased linearly with increasing proportions of glycerol in the diet. With increasing glycerol proportion in the diet, palmitic acid, oleic acid, linoleic acid, linolenic acid, and conjugated linoleic acid proportions in milk decreased linearly, while most of the short and medium chain FFA proportions in milk increased. To conclude, glycerol, as an energy feed, can substitute barley up to 18% of dietary DM for dairy cows in mid or late lactation without affecting milk quality. However, including more than 12% dietary glycerol might decrease ECM yield.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.006
      Issue No: Vol. 209 (2018)
       
  • Teat number parameters in Italian Large White pigs: Phenotypic analysis
           and association with vertnin (VRTN) gene allele variants
    • Authors: Stefania Dall'Olio; Anisa Ribani; Giulia Moscatelli; Paolo Zambonelli; Maurizio Gallo; Leonardo Nanni Costa; Luca Fontanesi
      Abstract: Publication date: Available online 2 February 2018
      Source:Livestock Science
      Author(s): Stefania Dall'Olio, Anisa Ribani, Giulia Moscatelli, Paolo Zambonelli, Maurizio Gallo, Leonardo Nanni Costa, Luca Fontanesi
      Teat number (TN) is a major determinant of the mothering ability of sows that in turn influences their reproductive efficiency. Even if the total number of teats is routinely recorded in many pig breeding programmes, its individual side count is not commonly recorded and just few investigations have evaluated the bilateral symmetry of this morphological trait. Several studies in pigs have identified genes or genomic regions affecting teat traits. For example, polymorphisms in the vertnin (VRTN) gene have been associated with the number of thoracic vertebrae and with TN in a few pig breeds. In this study, we evaluated the phenotypic variability of traits related to teat count including number of teats on the left (LTN) and right (RTN) side, TN, maximum number of teats between the two sides (MAX) and teat asymmetry traits (signed and absolute difference between RTN and LTN) in 793 Italian Large White heavy pigs. Furthermore, we genotyped these pigs for the AB554652:g.20311_20312ins291 VRTN gene polymorphism and evaluated its effect on the recorded teat parameters. This polymorphism was significantly associated (P<0.0001) with all investigated traits, except the asymmetry traits. The estimated additive effects were 0.35 for TN, 0.19 for RTN, 0.16 for LTN and 0.17 for MAX, with a favourable effect of the mutated Q allele (the allele derived by the inserted 291bp fragment). Selection for the VRTN Q allele could expedite the genetic progress for teat number and thus might be important to improve reproduction performances of the Italian Large White heavy pig breed.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.020
       
  • An evaluation of metabolizable energy content of main feed ingredients for
           growing pigs when adding dietary lysophospholipids
    • Authors: M.J. Kim; A.R. Hosseindoust; Y.H. Choi; A. Kumar; S.M. Jeon; S.H. Lee; B.Y. Jung; B.J. Chae
      Abstract: Publication date: Available online 2 February 2018
      Source:Livestock Science
      Author(s): M.J. Kim, A.R. Hosseindoust, Y.H. Choi, A. Kumar, S.M. Jeon, S.H. Lee, B.Y. Jung, B.J. Chae
      The present study was conducted to test whether the dietary supplementation of lysophospholipids (LPL) affects digestible energy (DE) content of feed ingredients, nutrient digestibility, and growth performance of growing pigs. In Exp. I, 8 growing pigs were alternatively used for 8 dietary treatments including 4 feed ingredients (corn, soybean meal, distiller's dried grains with solubles, and animal fat), and 2 LPL concentrations (0 and 0.1%) in 6 periods to determine DE and metabolizable energy (ME) content. In Exp. Ⅱ, 200 growing pigs were randomly allotted to 4 treatments on the basis of body weight with 2 concentrations of fat (high and low) and 2 concentrations of LPL (0 and 0.1%). The experimental diets were fed for 42 d in 2 phases. In Exp. I, gross energy (GE) digestibility, feed DE, and ME were increased in animal fat when LPL were added to the diet. In Exp. II, the pigs fed LPL showed greater (P < 0.05) digestibility of EE, GE, crude protein (CP), and DM In phase II. Pigs fed a high-fat diet had greater (P < 0.05) digestibility of EE, and GE. Gross energy retention was greater (P < 0.05) in pigs fed the high-fat diet compared with those fed the low-fat diet in phase II. During phase I, the average daily gain (ADG) of pigs fed the high-fat diet was greater (P < 0.05) than that for pigs fed the low-energy diet. During the second phase, ADG was increased in LPL and high-fat diets (P < 0.05). The overall results showed that pigs fed the LPL or high-fat treatments had greater ADG and feed to gain ratio (F/G). Considering the 2 experiments, it can be concluded that LPL increase the ME of animal fat and improves ADG and F/G in pigs.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.014
       
  • Exploring the association between polymorphisms at 3’UTR SLC11A1 gene
           microsatellites and resistance to tuberculosis: A case-control study in
           Bos taurus dairy cattle
    • Authors: Flavia C. Hasenauer; Sergio G. Garbaccio; Maria E. Caffaro; Carlos Garro; Pablo Huertas; Mario A. Poli; Carlos A. Rossetti
      Abstract: Publication date: Available online 2 February 2018
      Source:Livestock Science
      Author(s): Flavia C. Hasenauer, Sergio G. Garbaccio, Maria E. Caffaro, Carlos Garro, Pablo Huertas, Mario A. Poli, Carlos A. Rossetti
      Bovine tuberculosis is a contagious infectious disease that causes significant economic impact in dairy and meat farms throughout the world. Multiple factors, including host genome, determine the outcome of the infection. Several studies have associated polymorphisms at the two microsatellites (Ms) -Ms1 and Ms2- at the 3´unstranslated (UTR) region of the SLC11A1 bovine gene with innate resistance or susceptibility to some facultative intracellular bacterial infections, such as Brucella abortus and Mycobacterium avium subsp. paratuberculosis. Today, the few studies that investigated the association of those polymorphisms with innate resistance or susceptibility to tuberculosis in cattle, have shown opposite results. The aim of this study was to evaluate the role, if any, of the Ms1 and/or Ms2 polymorphisms at the 3´UTR of the SLC11A1 gene in Mycobacterium bovis infection phenotypes in Bos taurus dairy cattle. Jersey (n=149) and Holstein (n=427) cattle under risk of natural M. bovis infection were classified like controls (n=326) and cases (n=250) based on the response to caudal fold tuberculin skin test. Cattle population was genotyped by capillary electrophoresis based on polymorphisms in Ms1 and Ms2 at the 3´UTR SLC11A1 gene. The results presented here showed a lack of association (p > 0.05) between polymorphisms at the 3´UTR SLC11A1 gene and the response to tuberculin skin test in dairy Bos taurus cattle. Further studies are necessary to establish robustly genes or genome regions determining the innate R/S phenotype to Mycobacterium bovis.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.012
       
  • Effects of modified montmorillonite adsorbent on performance, egg quality,
           serum biochemistry, oxidation status, and immune response of laying hens
           in late production
    • Authors: X.Y. Qu; J.F. Chen; C.Q. He; F. Chi; S.L. Johnston
      Abstract: Publication date: Available online 2 February 2018
      Source:Livestock Science
      Author(s): X.Y. Qu, J.F. Chen, C.Q. He, F. Chi, S.L. Johnston
      This study was conducted to investigate the effects of dietary supplementation with calcium montmorillonite (Ca-MMT) on layers’ oxidation status, immune response, serum biochemistry, performance, and egg quality. A total of four hundred-eighty 75-wk-old laying hens were randomly assigned to 5 treatments with 8 replicates per treatment and 12 hens in each replicate. The hens were fed the basal diets supplemented with 0, 0.3, 0.6, 0.9, or 1.2g Ca-MMT/kg for 70 d. The Ca-MMT supplementation linearly or quadratically (P < 0.05) increased yolk index, serum total superoxide dismutase activity, and interleukin-2 and immunoglobulin G concentrations at d 35, and shell thickness, and serum and liver glutathione peroxidase activity at d 70. With increasing supplementation of Ca-MMT in the basal diet, serum activity of alkaline phosphatase decreased both linearly and quadratically (P < 0.05) at d 35, and alanine aminotransferas activity and tumor necrosis factor-alpha concentration decreased linearly or quadratically (P < 0.05) at d 70. The evidence indicates that increasing Ca-MMT concentration improved certain quality measurements, and partially enhancing hens’ antioxidant capability and immune function.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.021
       
  • Single nucleotide polymorphisms within rabbits (Oryctolagus cuniculus)
           fatty acids binding protein 4 (FABP4) are associated with meat quality
           traits
    • Authors: Ł. Migdał; K. Kozioł; S. Pałka; W. Migdał; A. Otwinowska-Mindur; M. Kmiecik; A. Migdał; D. Maj; J. Bieniek
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): Ł. Migdał, K. Kozioł, S. Pałka, W. Migdał, A. Otwinowska-Mindur, M. Kmiecik, A. Migdał, D. Maj, J. Bieniek
      Fatty acids binding protein 4 (FABP4; a-FABP) belongs to a family of proteins interacting with fatty acids and influencing lipid metabolism. Thus it may play an important role in rabbit fatness traits. The work was aimed at identifying SNPs within the rabbit FABP4, and their association with fatness traits. Panel of 20 animals’ DNA with varying content of intramuscular fat were sequenced. Alignment of the sequences obtained revealed seven polymorphic sites within the rabbit FABP4: four silent (g.97156738G>A/ rs880004109; g.97156696A>G/ rs880004111; g.97156168G>A/ rs88000411 and g.97156084G>A/ rs880004114), two located in introns - g.97156187A>C/ rs880004112 and g.97156025G>A/ rs880004115, and one missense mutation g.97156692C>A/ rs880004110 (D77Y). A pool of data from 320 F2 crossbreds Belgian Giant Grey x New Zealand White rabbits was used for association analysis. The Bonferroni adjustment was applied for correction for multiple testing. Statistical analysis showed association for g.97156025G>A for L⁎45 (P= 0.0001) and L⁎24 (P= 0.0001) values after slaughter of m. longissimus lumborum. Moreover correlations between analyzed traits were calculated. We conclude that SNPs within the rabbit FABP4 gene are associated with fatness and meat traits and therefore they have potential use in breeding programs.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.018
       
  • Effects of chito-oligosaccharide supplementation with low or medium
           molecular weight and high degree of deacetylation on growth performance,
           nutrient digestibility and small intestinal morphology in weaned pigs
    • Authors: Boonrit Thongsong; Sureerat Suthongsa; Rath Pichyangkura; Sarinee Kalandakanond-Thongsong
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): Boonrit Thongsong, Sureerat Suthongsa, Rath Pichyangkura, Sarinee Kalandakanond-Thongsong
      Chito-oligosaccharide (COS) supplementation in nursery diets has been found to improve piglets’ performance. However, little is known on which COS characteristics are responsible for its effect. The present study was designed to further study how COS characteristics: molecular weight (MW) and degree of deacetylation (DD); affect the growth performance, nutrient digestibility, and small intestinal modifications in weaning pigs. For this purpose, 48 weanling pigs were divided into 4 groups (12 animals per group) and received either a basal diet or a basal diet supplemented with 150mg/kg of COS which differed in MW and DD: 8kDa and ~90% DD (8kDa~90%), 65kDa and ~80% DD (65kDa~80%), and 65kDa and ~90% DD (65kDa~90%). The experiment lasted 56 days. There were treatment effects on pigs’ body weight gain (BWG), average daily gain (ADG), average daily feed intake (ADFI), blood urea nitrogen (BUN), digestibility of crude protein, fat and calcium, small intestinal morphology and crypt cell proliferation (P < 0.05, respectively). Throughout the study, pigs supplemented with 8kDa~90% COS showed significantly enhanced BWG, ADG, and ADFI when compared to those supplemented with 65kDa~80% COS (P < 0.05, respectively). The enhanced growth performances in pigs supplemented with 8kDa~90% COS was supported by an increase in ADFI (P < 0.05), and improved ileal digestibility of crude protein and crude fat (P < 0.01, respectively). Pigs supplemented with 8kDa~90% COS also had increased absorption capacity as indicated by elongated villus height and increased villus height to crypt depth ratio of the small intestinal segments (P < 0.05, respectively), and more active cell division as indicated by increased Ki-67 marker at jejunal crypt cells (P < 0.05) on day 28 and 56 of the experiment. These data suggest that 8kDa~90% might be the most effective form of COS to improve feed intake, and promote nutrient digestibility and absorption when supplemented at 150mg/kg in the diet.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.011
       
  • The effect of citric acid acidification of drinking water on growth
           performance, cecal pH, and cecal microflora of meat duck
    • Authors: H. Liao; X.P. Wu; K.Y. Zhang; X.M. Ding; S.P. Bai; J.P. Wang; Q.F. Zeng
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): H. Liao, X.P. Wu, K.Y. Zhang, X.M. Ding, S.P. Bai, J.P. Wang, Q.F. Zeng
      Two experiments were conducted to evaluate the effects of acidification of drinking water with citric acid (CA) on growth performance, cecal pH, and cecal microflora of meat ducks. Preparing tap water containing 5 concentrations of CA (0, 0.021, 0.034, 0.068, and 0.449%) to lower pH of the solutions from 7.80 (tap water) to 5.45, 4.45, 3.50, and 2.56 was assessed, respectively. A total of 120 1-d-old ducks in Exp. 1, and another 120 15-d-old ducks in Exp. 2 were randomly allocated to 5 drinking water treatments with 6 replicate cages of 4 ducks, respectively. The experimental period was from 1 to 14 d of age in Exp. 1, and was from 15 to 35 d of age in Exp. 2. In both experiments, drinking water administration of incremental concentrations of CA linearly and quadratically reduced (P < 0.05) water intake of ducks. Feed intake and daily weight gain of ducks in Exp.1 linearly decreased (P < 0.05), while feed intake in Exp.2 linearly increased (P < 0.05), and the absolute quantitative level of E. coli (d 35, Exp.2) in the cecum of ducks quadratically decreased (P < 0.05) as supplementation of drinking water with CA increased. Data obtained from Exp. 1 indicated that ducks from 1 to 14 d of age should not be given acidified drinking water; however, acidified drinking water with 0.068% CA (pH 3.50) can be supplied to ducks from 15 to 35 d of age based on data from Exp. 2.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.010
       
  • Estimation of the metabolic rate by assessing carbon-13 turnover in
           broiler tissues using the stable isotope technique
    • Authors: V.C. Pelícia; P.C. Araujo; F.G. Luiggi; A.C. Stradiotti; J.C. Denadai; J.R. Sartori; P.D.G. Pacheco; L.C. Dornelas; E.T. Silva; C.R. Souza-Kruliski; G.E.M. Pimenta; C. Ducatti
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): V.C. Pelícia, P.C. Araujo, F.G. Luiggi, A.C. Stradiotti, J.C. Denadai, J.R. Sartori, P.D.G. Pacheco, L.C. Dornelas, E.T. Silva, C.R. Souza-Kruliski, G.E.M. Pimenta, C. Ducatti
      The aim of this study was to estimate the metabolic rate of broiler tissues by assessing carbon turnover in different growth phases by using the stable isotope technique and by evaluating the natural changes in Carbon-13 (13C) between C3 and C4 cycle plants. Six-hundred 1-day-old broiler chicks were divided into six groups and subjected to dietary changes containing different isotopic values at 7, 14, 21, 28, and 35 days of age. Birds of Group 1 received diets composed predominantly of C3 cycle plants shortly after accommodation, while birds of other groups remained predominantly fed with C4 diet. The diet of Group 2 was mainly replaced by C3 diet on the 7th day of age. Group 3 started to receive C3 diet on the 14th day of age, whereas the diet of Group 4 was replaced on the 21st, Group 5 on the 28th. In Group 6, the substitution occurred on the 35th day of age. Samples of the pectoral muscle, keel, tibia, legs muscle, intestinal mucosa, blood, plasma, and feathers were collected. Carbon isotope ratios were determined by mass-spectrometry of isotope ratios. To measure the speed of carbon substitution after a set interval (turnover), a time exponential function was employed and obtained by exponential equations of the first order calculated with Minitab® 16 software. The carbon half-life varied from 1.78 to 8.20 days for the pectoral muscle, from 1.91 to 12.24 days for the keel, from 2.32 to 10.71 days for the tibia, from 1.87 to 9.43 days for the leg muscle, from 0.8 to 1.58 days for the intestinal mucosa, from 0.64 to 1.71 days for the plasma, from 2.61 to 11.07 days for blood, and from 1.84 to 28.41 days for the feathers during the total growth phase. With the exception of tibia and blood, all other tissues presented a high metabolic rate in the first week of the broilers’ life. The metabolic rate of tissues is faster in younger animals, and the metabolism slows down as the broilers get older. The metabolic rates in the pectoral muscle, keel, tibia, and feathers decreased with age, whereas those of the plasma and intestinal mucosa were high in all evaluated periods; thus, these tissues can be used to study traceability of feed at all stages of the broilers’ life.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.019
       
  • Litter size of Danish crossbred sows increased without changes in sow body
           dimensions over a thirteen year period
    • Authors: S.E. Nielsen; A.R. Kristensen; V.Aa. Moustsen
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): S.E. Nielsen, A.R. Kristensen, V.Aa. Moustsen
      The purpose of this study was to investigate if body dimensions of Danish crossbred sows (Yorkshire x Landrace) had increased compared to a previous Danish study from 2004. In addition, and as an expected potential benefit of increased body dimensions, a potential correlation between body dimensions and litter size was also investigated. Depth, width, length and height were measured from 405 Danish crossbred sows in 10 different herds, classified in groups of parity 1, 2, 3, 4, 5, 6 and ≥ 7. By Linear Mixed-Effects Models with depth, width, length and height in turn as response variable and parity and herd as explanatory variables, estimated means, 5th and 95th percentiles, minimum and maximum observation were recorded. Furthermore, a weighted index for litter size (denoted as the “litter size potential”) was used as response variable with depth, width, length, height and parity as explanatory variables in an additive linear model. The factors were removed individually and in combination to test the effect. Mean depth, width, length and height were estimated to 66, 43, 192 and 90 cm, respectively, for full grown sows (parity ≥ 5). Sows’ body dimensions were not found to have increased since 2004. The result of this study did not find significant (P < 0.05) effect of sow dimensions on litter size.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.015
       
  • Meta-analysis of the relationships between reproduction, milk yield and
           body condition score in dairy cows
    • Authors: Nicolas Bedere; Erwan Cutullic; Luc Delaby; Florence Garcia-Launay; Catherine Disenhaus
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): Nicolas Bedere, Erwan Cutullic, Luc Delaby, Florence Garcia-Launay, Catherine Disenhaus
      The present study aimed to investigate the relationships between each step of the reproductive process (cyclicity, estrus, and fertility) and both milk production and body reserves management. The database included 102 studies and 300 treatments collected on electronic databases. Coding for each type of experimental factor enabled within and between experiment variation to be distinguished, and to select subsets of experiments with common objectives in order to avoid inappropriate aggregation of results across studies with very different objectives. Finally, the models were based on limited numbers of experiments (from 14 to 30 treatments originating from 7 to 15 distinct experiments) because (i) only data coded for diet and genetic factors were analyzed, separately (studies on other factors such as milking frequency and parity were too scarce); (ii) a minimum of variation of the explanatory variable was set to enable the quantification of the relationship; (iii) few studies reported comparable reproductive, production and body reserves traits. The results of the meta-analyses showed that the commencement of luteal activity (C-LA) was not associated with milk yield and that the relationship between C-LA and body condition score (BCS) at calving was quadratic (with an optimal BCS at calving around 3.10 on a 0–5 scale). Although the interval from calving to first observed estrus (COE1) is partly composed of C-LA, it was not associated with BCS. For each additional 1kg of milk yield produced at both peak and over the initial 14 weeks of lactation, COE1 was delayed by 1.1 days. The conception rate to first insemination (CRAI1) was reduced by 2.0% (of inseminated cows) and by 2.2% for each additional 1kg of milk yield at peak and at service respectively. Moreover, CRAI1 was increased by 38.2% and 22.0% for each additional 1 score of BCS at service and at nadir (i.e. lowest BCS) respectively. Finally, risk of pregnancy (PR) was not associated with milk yield. However, PR was increased by 42.8% (of cows) and 16.8% for each additional unit of BCS at calving and at nadir, respectively. This meta-analysis showed that postpartum cyclicity of dairy cows was mainly associated with BCS at calving, whereas estrus expression was mainly associated with milk yield and fertility with both BCS and milk yield. Genetic and nutritional strategies that target a BCS of 3.10 and limit both BCS loss and peak milk yield could be an effective way to improve reproduction.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.017
       
  • Milk yield and urinary-nitrogen excretion of dairy cows grazing forb
           pasture mixtures designed to reduce nitrogen leaching
    • Authors: R.H. Bryant; B. Welten; D. Costall; P.R. Shorten; G.R. Edwards
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): R.H. Bryant, B. Welten, D. Costall, P.R. Shorten, G.R. Edwards
      The effect of including a mixture of forbs in a standard perennial ryegrass-white clover pasture, with or without Italian ryegrass was investigated in a two-period grazing study comparing urinary nitrogen (N) excretion and milk yield of dairy cows in late lactation. Forty-eight mixed age, Holstein Friesian x Jersey cows were assigned to replicated, balanced, groups of six and offered one of four pasture treatments. Pasture types were either a perennial ryegrass-based pasture (PRG) with white clover or a forb-containing mixed pasture (MIX) including perennial ryegrass, white clover, chicory, plantain and lucerne. A second factor was the inclusion of Italian ryegrass (PRG+I and MIX+I). During Period I, ten cows in each of the MIX and PRG treatments were fitted with urine sensors to measure urine N parameters (urination frequency, volume and N concentration). During Period II, milk yield was measured from cows on all four pasture types. In both the ryegrass and forb pasture types, legume content exceeded 30% of the DM and in forb pastures chicory and plantain accounted for over 30% of the DM. Italian ryegrass in the MIX+I and PRG+I was respectively 5 and 15% of the DM. Digestibility and crude protein was similar for all pasture types, but fibre content was lower for forb pastures. During Period I, there was no effect of pasture type on the amount of N per urination event (averaged 13gN/event) and daily urine-N excreted (190gN/cow/day). However, pasture type affected the diurnal pattern in urine-N excretion with MIX pastures having a lower urine N loading per event during the day and higher urine N loading at night compared with PRG pastures. During Period II, milk yield was greater for forb compared with ryegrass pasture types (1.66 vs 1.50kg MS/cow/d). There was no effect of Italian ryegrass on milk yield due to low botanical content. This study demonstrated that forb containing pastures altered the diurnal pattern in urine-N excretion and offers opportunities to mitigate N leaching from grazed pastures whilst supporting high milk production in late lactation.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.009
       
  • A genome-wide association study of reproductive traits in a Yorkshire pig
           population
    • Authors: Md. Rasel Uzzaman; Jong-Eun Park; Kyung-Tai Lee; Eun-Seok Cho; Bong-Hwan Choi; Tae-Hun Kim
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): Md. Rasel Uzzaman, Jong-Eun Park, Kyung-Tai Lee, Eun-Seok Cho, Bong-Hwan Choi, Tae-Hun Kim
      Genome-wide association studies (GWASs) have been extensively utilized to identify economically important trait loci in livestock animals. We performed a GWAS on Yorkshire sows for reproduction traits (the number of piglets born alive;NBA, the total number of piglets born;TNB, the weight shortfall number, the total number of suckling piglets, and the number of pigs weaned). A total of 1061 sows were genotyped using the Illumina PorcineSNP60 BeadChip. Principal component analysis revealed no significant population stratification. We identified a total of 15 single nucleotide polymorphisms (SNPs) of which only one reached the Bonferroni level of significance (P < 2.33E-07) and the remaining fourteen SNPs were suggestive of association for the reproductive traits of interest (P < 5E-05). The heritability estimates obtained by all SNPs were 0.11 ± 0.04, 0.14 ± 0.05, 0.15 ± 0.05, 0.14 ± 0.05, and 0.02 ± 0.03 for NBA, TNB, weight shortfall number, total number of suckling piglets, and number of pigs weaned, respectively. The two most significant SNPs, rs81465399 (P = 8.05E-08) and rs80991683 (P = 1.55E-06) on SSC17, were associated with weight shortfall number. In addition, SNP rs81356596 (P = 1.20E-05) on SSC2 was associated with the total number of suckling piglets. Another two SNPs, rs81454514 (P = 1.07E-05) and rs81454465 (P = 1.56E-05) on SSC15 and associated with NBA, were located near the reported quantitative trait locus (QTL) region of both the NBA and TNB traits. The heritability estimate for the number of pigs weaned was the lowest among all five pig reproductive traits in our analysis. Overall, we found a number of significant SNPs, some of them belonging to an uncharacterized locus, LOC102165882, along with two important genes, ACSL3 and CD59, with various physiological functions relevant to reproduction.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.005
       
  • BOVINE SUBCLINICAL MASTITIS REDUCES MILK YIELD AND ECONOMIC RETURN
    • Authors: J.L. Gonçalves; C. Kamphuis; C.M.M.R. Martins; J.R. Barreiro; T. Tomazi; A.H. Gameiro; H. Hogeveen; M.V. dos Santos
      Abstract: Publication date: Available online 31 January 2018
      Source:Livestock Science
      Author(s): J.L. Gonçalves, C. Kamphuis, C.M.M.R. Martins, J.R. Barreiro, T. Tomazi, A.H. Gameiro, H. Hogeveen, M.V. dos Santos
      The effect of different pathogens was studied by evaluating the contralateral (healthy and infected) mammary quarters of 146 lactating cows. The impact of SM on economic return (quarter milk yield × milk price) was determined by applying milk payment estimates on milk collected from healthy vs. infected glands. Cows were considered infected when they had at least 2 out of 3 weekly composite SCC results > 200×103 cells/mL and a microbiological culture (MC) positive result from composite foremilk samples, collected in the third week of sampling. Infected cows were evaluated a second time within 15 days and had milk yield measured at the quarter level and foremilk samples collected by aseptic technique for analysis of MC, milk composition and SCC. Of the 611-composite milk samples, 397 (65%) were culture-negative, and 214 (35%) were culture-positive and the most frequent isolated bacteria were Corynebacterium spp. (7.9%), coagulase negative staphylococci (5.8%), Staphylococcus aureus (5.3%), Streptococcus uberis (4.6%), Streptococcus agalactiae (3.9%), other environmental streptococci (2.4%), Gram-negative isolates (2.4%), Enterococcus spp. (1.4%) and Streptococcus dysgalactiae (0.7%). A total of 55 pairs of healthy contralateral quarters (control) were compared, and no difference was observed between them when evaluating SCC, milk yield, fat and protein concentration and economic return. A total of 124 pairs of healthy had lower SCC (274.9×103 cells/mL) than infected contralateral quarters (SCC of 1,038.5×103 cells/mL). At the quarter level, IMI caused by minor pathogens had no effect on SCC, milk yield and economic return. Subclinical mastitis caused by contagious and environmental pathogens increased SCC and decreased milk yield when compared with healthy contralateral quarters. Moreover, quarters infected by contagious pathogens had increased concentrations of milk protein and fat when compared with healthy contralateral quarters. Therefore, the milk economic return was lower in quarters with SM caused by environmental pathogens (US$ 0.18/quarter.milking) and contagious (US$ 0.22/quarter.milking) when compared with healthy contralateral quarters. The milk losses ranged from 0.07kg/quarter.milking to 1.4kg/quarter.milking and the economic losses ranged from US$ 0.02 to 0.4/quarter.milking according to the pathogen causing SM.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.016
       
  • Effect of live yeast supplementation on gastric ecosystem in horses fed a
           high-starch diet
    • Authors: Samy Julliand; Agathe Martin; Véronique Julliand
      Abstract: Publication date: Available online 19 January 2018
      Source:Livestock Science
      Author(s): Samy Julliand, Agathe Martin, Véronique Julliand
      Starch/grain intake has been reported to be at risk for equine gastric lesions of the squamous mucosa (Equine Squamous Gastric Disease – ESGD). Exposition to VFAs and lactic acid, end-products of the fermentation occurring in the gastric ecosystem, can cause ESGD. As in the hindgut, supplementing yeast to high starch/grain diet could increase lactate-utilizing bacteria and thus limit the production of lactic acid and eventually the acidity. The objective of this study was to investigate the effect of two levels of Saccharomyces cerevisiae (Sc47) supplementation on gastric ecosystem in horses fed high-starch diet. Six horses were assigned in a 3*3 Latin square design with three supplement treatments: 10.109 (dose 1) or 10.1010 (dose 10) cfu of zootechnical additive Sc47 per day or a control. Each experimental period lasted 21 days and was separated from the next one by a wash-out period of 21 days. During experimental periods, horses received a 70:30 ratio hay:barley (2.3kg DMI / 100kg BW / day) and 50g per day of the additive. Gastric content samples were collected on day 18 of each experimental period 3h and a half after morning barley meal to measure: pH, bacterial populations (total anaerobic, amylolytic and lactate-utilizing bacteria), and fermentation products (VFAs and lactic acid). The observation of the stomach with the video-endoscope did not reveal any alteration of the squamous gastric mucosa. Total anaerobic bacteria and amylolytic concentrations were lower with Sc47 dose 10 compared to placebo (P = 0.03 and 0.04, respectively). With dose 10 of Sc47, lactate-utilizing bacteria concentrations decreased compare to Sc47 dose 1 (P = 0.03) and placebo (P = 0.004). No treatment effect was observed on total VFAs and lactic acid concentrations. Butyric and valeric acids concentrations showed higher concentration with Sc47 dose 1 compared to other treatments during period 1. Although, the pHs were numerically less acidic with live yeast, they were not significantly modified by the treatment. Globally, there was a dose effect of Sc47 on bacteria concentrations which all decreased or tended to decrease when the level of yeast increased in the diet. Further investigation is required to know whether live yeast supplementation could be part of the strategy to reduce gastric fermentation of starch and thereby help reducing the risk of ESGD.

      PubDate: 2018-02-04T19:29:22Z
      DOI: 10.1016/j.livsci.2018.01.007
       
  • Modulation of the acute phase response following a lipopolysaccharide
           challenge in pigs supplemented with an all-natural Saccharomyces
           cerevisiae fermentation product
    • Authors: Nicole C. Burdick Sanchez; Jeffery A. Carroll; Paul R. Broadway; Benjamin E. Bass; Jason W. Frank
      Pages: 1 - 4
      Abstract: Publication date: February 2018
      Source:Livestock Science, Volume 208
      Author(s): Nicole C. Burdick Sanchez, Jeffery A. Carroll, Paul R. Broadway, Benjamin E. Bass, Jason W. Frank
      This study was designed to determine if feeding a Saccharamyces cerevisiae fermentation product to weaned pigs would reduce the acute phase response (APR) following an lipopolysaccharide (LPS) challenge. Pigs (n = 20; 6.4 ± 0.2kg BW) were obtained and transported to a nursery facility. Pigs were housed individually with ad libitum access to feed and water. Pigs were weighed upon arrival and assigned to 1 of 2 treatment diets (n = 10 pigs/treatment) for 18 d: 1) non-medicated starter diet (Control); 2) Control diet + Saccharomyces cerevisiae fermentation product (XPC; 2kg/MT; Diamond V Original XPC™). Pigs were anesthetized on d 7 and 14 for insertion of an intraperitoneal (IP) temperature recording device and jugular catheter, respectively. On d 15, pigs were challenged i.v. with LPS (25µg/kg BW). Blood samples were collected at 0.5-h (serum) and 1-h (complete blood cell counts) intervals from −2 to 8h and at 24h relative to LPS challenge at 0h. There was a treatment effect (P ≤ 0.002) for serum TNF-α and IL-6 such that concentrations were greater in XPC-supplemented pigs than Control pigs (116.5 ± 5.0 vs. 90.9 ± 5.2pg/mL TNF-α; 188.3 ± 13.4 vs. 133.4 ± 11.7pg/mL IL-6; respectively) following LPS challenge. Administration of LPS increased IP temperature (P < 0.01), however, there was no effect of treatment (P = 0.12). Thus, feeding a Saccharamyces cerevisiae fermentation product to weaned pigs increased the pro-inflammatory cytokine response to an LPS challenge.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.022
      Issue No: Vol. 208 (2017)
       
  • Effect of vitamin E supplementation on growth performance, meat quality,
           and immune response of male broiler chickens: A meta-analysis
    • Authors: Mariana A. Pompeu; Luigi F.L. Cavalcanti; Fabio L.B. Toral
      Pages: 5 - 13
      Abstract: Publication date: February 2018
      Source:Livestock Science, Volume 208
      Author(s): Mariana A. Pompeu, Luigi F.L. Cavalcanti, Fabio L.B. Toral
      The effect of vitamin E supplementation on the growth performance, carcass traits, meat quality, and immune response of male broiler chickens was studied using a meta-analysis. The database was consisted of 51 scientific papers published in peer-reviewed journals. The dependent variables for meta-analysis included final body weight, average daily gain, daily feed intake, feed conversion ratio, vitamin E concentration in the muscle, tissue polyunsaturated fatty acid concentration, lipid peroxidation value, post mortem pH, heterophil to lymphocyte ratio, and total immunoglobulins. Linear mixed models were used to analyze the data. Vitamin E supplementation did not influence growth performance, as the estimated slopes were not different from zero, with P-values equal to 0.92 for final body weight, 0.81 for average daily gain, 0.31 for daily feed intake, and 0.83 for feed conversion ratio. Dietary vitamin E supplementation increased the vitamin E content in the muscle (P = 0.001), did not change the polyunsaturated fatty acid concentration, and decreased the lipid peroxidation (P = 0.01). The immune response was improved, the heterophil to lymphocyte ratio was constant, and the total immunoglobulins were increased (P = 0.037) by dietary vitamin E supplementation. With regard to broiler chicken performance, there seemed to be no relationship between dietary vitamin E supplementation and growth performance. There is ample indication that meat quality and immune response could be improved by dietary vitamin E supplementation.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.021
      Issue No: Vol. 208 (2017)
       
  • Apparent digestibility, rumen fermentation, digestive enzymes and urinary
           purine derivatives in yaks and Qaidam cattle offered forage-concentrate
           diets differing in nitrogen concentration
    • Authors: J.W. Zhou; H. Liu; C.L. Zhong; A.A. Degen; G. Yang; Y. Zhang; J.L. Qian; W.W. Wang; L.Z. Hao; Q. Qiu; Z.H. Shang; X.S. Guo; L.M. Ding; R.J. Long
      Pages: 14 - 21
      Abstract: Publication date: February 2018
      Source:Livestock Science, Volume 208
      Author(s): J.W. Zhou, H. Liu, C.L. Zhong, A.A. Degen, G. Yang, Y. Zhang, J.L. Qian, W.W. Wang, L.Z. Hao, Q. Qiu, Z.H. Shang, X.S. Guo, L.M. Ding, R.J. Long
      Yaks (Bos grunniens) and Qaidam yellow cattle (Bos taurus) are indigenous to the Qinghai-Tibetan Plateau and graze natural pasture all year. Yaks are raised at higher elevations than cattle and are not offered supplementary feed whereas cattle receive supplementary feed and are sheltered at night during winters. We hypothesized that the species differ in metabolism of energy and nitrogen (N) and predicted that the differences would favour yaks to the harsh conditions of the plateau. To test our prediction, we examined nutrient digestibility, rumen fermentation, digestive enzymes and urinary purine derivatives (PD) in yaks and cattle offered forage-concentrate diets differing in N concentration. Four castrated yaks and 4 castrated cattle of similar ages (2.5 years) and body weights (200kg) were used in two concurrent 4×4 Latin square designs. There was no difference (P > 0.05) between yaks and cattle in apparent digestibilities of dietary nutrients, concentrations of ruminal N components and activities of digestive enzymes (P > 0.05). Crude protein and acid detergent fiber digestibilities increased linearly (P < 0.001) while neutral detergent fiber digestibility decreased linearly (P < 0.05) with increased dietary N intake for both species. Ruminal concentration of total VFA was greater in yaks than in cattle across diets (P < 0.05), but pH was similar between species (P > 0.05), and both variables were not affected by dietary N content (P > 0.05). As dietary N increased, ruminal concentrations of ammonia, urea and amino acids increased linearly (all P < 0.001), peptides tended to increase (P < 0.10), but soluble protein remained constant (P > 0.10) for both species. The activity of carboxymethylcellulase decreased linearly (P < 0.01) while activities of deaminase and urease increased linearly (P < 0.001) with increased dietary N. Urinary PD and components did not differ between species (P > 0.10); however, the PD nitrogen index (PNI) was greater in yaks than in cattle for the lowest N diets (linear dietary N × species, P < 0.01). With an increase in dietary N, urinary total PD, allantoin and uric acid increased linearly (P < 0.001), as did microbial N synthesis (P < 0.001), whereas PNI decreased linearly (P < 0.001). In addition, microbial N production was greater in yaks than in cattle (P < 0.05). We concluded that energy and nitrogen metabolism were more efficient in yaks than in Qaidam cattle, which enable yaks to better cope with the harsh foraging conditions of the Qinghai-Tibetan Plateau.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.020
      Issue No: Vol. 208 (2017)
       
  • Estimation of genetic parameters for cow age at last calving under
           different censorship criteria
    • Authors: S.B. Ramos; S.L. Caetano; G.J.M. Rosa; R.P. Savegnago; E.L. Kern; P.A. Bernardes; R.B. Lôbo; D.P. Munari
      Pages: 40 - 43
      Abstract: Publication date: February 2018
      Source:Livestock Science, Volume 208
      Author(s): S.B. Ramos, S.L. Caetano, G.J.M. Rosa, R.P. Savegnago, E.L. Kern, P.A. Bernardes, R.B. Lôbo, D.P. Munari
      Cow longevity measured by age at last calving was evaluated using a censorship criterion that consisted of the difference between the dates of age at last calving and the last calving on the farm. If this difference was greater than certain value, the cow failed, indicating that it should be discarded. Otherwise, the cow was censored indicating the possibility of future calving. The aim of this study was to estimate heritability and breeding values of bulls for longevity considering three different censorship criteria, 16, 26 and 36 months, using Weibull proportional hazard sire model. The 16-month criterion was proposed because it is the estimated average interval between births in Nellore. The 26-month criterion was proposed because it is an average value between 16 and 36 months. Lastly, the 36-month criterion was considered a long time interval for the cow have a new calving. The Spearman correlation test was used to compare the rankings of the bulls regarding the estimates of breeding values for longevity considering the different censorship criteria. The records of 21996 Nellore cows were used. The cows were the daughters of 2113 bulls from 13 farms that participate in the Nellore breeding program of the National Association of Breeders and Researchers (ANCP). Age at first calving was considered a fixed effect while the random effect was the contemporary group (season, year of birth, and herd) and sire. Heritability estimates for cow age at last calving were 0.1020, 0.1002 and 0.0871 for the 16, 26 and 36-month censorship criteria, respectively. The Spearman correlation estimates of sires’ rankings were −0.2124, 0.1348 and 0.1211 (P > 0.05) for the censorship criteria of 16–26 months, 16–36 months, and 26 and 36 months, respectively. Despite of the little genetic variance to age at last calving, this values were higher than those reported in the literature. The accuracy of the selected bulls varies depending on the criteria adopted. The Weibull proportional hazard sire model predicted the highest reliabilities for the 16-month criterion, compared to other censorship criteria studied, which can lead to increasing of reproductive and productive efficiency of cows in the herd, since the lower open days of cows and higher number of calves per cow in her productive life.

      PubDate: 2017-12-26T18:15:17Z
      DOI: 10.1016/j.livsci.2017.12.006
      Issue No: Vol. 208 (2017)
       
  • Genetic parameters and trends for traits of the Hereford and Braford
           breeds in Brazil
    • Authors: B.B.M. Teixeira; M.D. MacNeil; R.F. da Costa; N.J.L. Dionello; M.J. Yokoo; F.F. Cardoso
      Pages: 60 - 66
      Abstract: Publication date: February 2018
      Source:Livestock Science, Volume 208
      Author(s): B.B.M. Teixeira, M.D. MacNeil, R.F. da Costa, N.J.L. Dionello, M.J. Yokoo, F.F. Cardoso
      The objective of this study was to estimate genetic parameters and genetic trends of Hereford and Braford breeds for growth traits and visual scores. Data consisting of records for 205-day weight (W205), 550-day weight (W550), 345-day post weaning gain (PWG345), scrotal circumference at 550 days (SC), and muscling (MUS) and frame (FRA) scores also recorded at 550 days of age came from the PampaPlus genetic evaluation system. A series of animal models were fit to the data using Bayesian inference with uninformative priors. Genetic variance for W205 was partitioned into direct (W205d) and maternal (W205m) components. Posterior means of heritability estimates and 95% support intervals (2.5% ≤ h2 ≤ 97.5%) for W205d, W205m, W550, PWG345, SC, MUS, and FRA were 0,12 ≤ 0.13 ≤ 0,14; 0.08 ≤ 0,09 ≤ 0.11; 0.13 ≤ 0.16 ≤ 0.19; 0.04 ≤ 0.10 ≤ 0.18; 0.05 ≤ 0.15 ≤ 0.32; 0.10 ≤ 0.19 ≤ 0.29 and 0.06 ≤ 0.11 ≤ 0.20, respectively. Genetic correlations with W205d were positive for W550 (0.72 ≤ 0.82 ≤ 0.90), MUS (0.25 ≤ 0.53 ≤ 0.74) and FRA 0.29 ≤ 0.59 ≤ 0.80 and negative for W205m (− 0.63 ≤ − 0.57 ≤ − 0.50). The genetic correlation of PWG345 and W550 was also positive and large (0.59 ≤ 0.76 ≤ 0.88). Genetic correlations of MUS and FRA with each other (0.30 ≤ 0.53 ≤ 0.73) and with PWG (0.08 ≤ 0.33 ≤ 0.55 and 0.20 ≤ 0.44 ≤ 0.64) and W550 (0.10 ≤ 0.39 ≤ 0.63 and 0.07 ≤ 0.38 ≤ 0.64) were all positive. Use of performance information in selection decisions is supported by positive genetic trends for direct effects on W205d, PWG345, W550, MUS and FRA. However, the genetic trends were less than the expected gains that would result from use of a recommended selection index, suggesting that the index is not the only criterion currently used in the selection by Pampaplus breeders. It may be concluded that breeders favored larger, more rapidly growing, and more muscular animals in their selection decisions.

      PubDate: 2017-12-26T18:15:17Z
      DOI: 10.1016/j.livsci.2017.12.008
      Issue No: Vol. 208 (2017)
       
  • Effect of enzymatically hydrolyzed scallop visceral protein powder used as
           a replacement of fish meal on the growth performance, immune responses,
           intestinal microbiota and intestinal morphology of broiler chickens
    • Authors: R.E. Xing; H.Y. Yang; X.Q. Wang; H.H. Yu; S. Liu; X.L. Chen; P.C. Li
      Pages: 15 - 24
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): R.E. Xing, H.Y. Yang, X.Q. Wang, H.H. Yu, S. Liu, X.L. Chen, P.C. Li
      The purpose of this study was to investigate the potential of using dietary supplemental enzymatically hydrolyzed scallop visceral protein (EHSVP) and scallop visceral protein (SV) to replace fishmeal with regard to the growth performance, carcass characteristics, immune response, intestinal microbiota, and intestinal morphology of broiler chickens. A total of 300 1-d-old broiler chickens were randomly assigned to 6 treatments with 5 cages per treatment and 10 broiler chickens per cage. The broiler chickens received a basal diet supplemented with 3% fishmeal or different concentrations of EHSVP (1%, 2%, and 3%) and SV (2% and 3%) treatments until d 42. Broiler chickens fed a diet with 2% EHSVP supplementation exhibited a greater average daily weight gain (P < 0.05) and lower feed conversion ratio. The carcass yield, eviscerated yield, and leg muscle yield of broiler chickens fed a diet with 2% EHSVP supplementation were increased (P < 0.05) and the abdominal fat rate was decreased compared with broiler chickens fed fishmeal diet (P < 0.05). Broiler chickens fed a diet with 2% EHSVP supplementation were increased the activities of digestive enzymes (P < 0.05); moreover, it inhibited colonization of E. coli and Salmonella pathogenic bacteria and increased the numbers of Lactobacillus and Bifidobacterium (P < 0.05). For EHSVP and SV supplementation, especially 2% EHSVP, the length of the duodenum, jejunum, and ileum as well as the weight of spleen, thymus, and bursa immune organs were increased (P < 0.05). Furthermore, 2% EHSVP supplementation increased the villus height and villus height:crypt depth ratio and decreased the crypt depth (P < 0.05), thereby improving intestinal development. In conclusion, as a fishmeal replacement, EHSVP supplementation can significantly improve growth performance, carcass characteristics, and weight of immune organs as well as promote the development of the small intestine. At the same time, supplementation can also significantly improve gut health and the intestinal microbial environment in broiler chickens. A diet with EHSVP supplementation is more effective in improving the growth performance, carcass characteristics, immune response, intestinal microbiota, and intestinal morphology of broiler chickens than SV. Therefore, fishmeal can be partially replaced by EHSVP.

      PubDate: 2017-11-16T08:33:47Z
      DOI: 10.1016/j.livsci.2017.10.004
      Issue No: Vol. 207 (2017)
       
  • Flow cytometry sex sorting affects bull sperm longevity and compromises
           their capacity to bind to oviductal cells
    • Authors: José de Oliveira Carvalho; Roberto Sartori; Leandro Rodello; Gerson Barreto Mourão; Sony Dimas Bicudo; Margot A. N. Dode
      Pages: 30 - 37
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): José de Oliveira Carvalho, Roberto Sartori, Leandro Rodello, Gerson Barreto Mourão, Sony Dimas Bicudo, Margot A. N. Dode
      This study assessed the effect of flow cytometry sexing on sperm longevity and the capacity of sperm to bind to oviductal cells. Each ejaculate from four bulls was divided into two fractions: the first was immediately frozen as non sexed sperm (NS) and the second was sexed originating X- and Y-bearing sperm. The fourth treatment had sex-sorted X and Y sperm (XY) combined. Sperm from each group was assessed for sperm characteristics after thawing, after washing and at 2, 4, 8 and 12h of incubation at 39°C in 5% CO2 in air. For the binding test, sperm were incubated in sp-TALP medium for 30min or 24h with oviductal explants. Percentages of motility (58.1 ± 4.3 and 35.2 ± 4.4), progressive motility (46.1 ± 6.1 and 25.7 ± 4.8), mitochondrial membrane potential (79.2 ± 8.3 and 69.0 ± 6.3), plasma membrane stability (77.4 ± 4.6 and 19.4 ± 4.2), and live sperm with intact acrosome (57.2 ± 8.5 and 31.3 ± 7.9) were higher in NS than in XY, respectively (P < 0.05). Those differences were maintained for up to 8h. The sexing process did not affect the sperm binding to the explants after 30min. However, after 24h, XY had less (6.7 ± 2.0) sperm bound to explants than NS (23.6 ± 7.2). In conclusion, even though XY was of lower quality than NS, the decreases in quality in both NS and XY groups were similar between groups during incubation. Moreover, the sex-sorting process affected the ability of sperm to remain bound to oviductal explants.

      PubDate: 2017-12-26T18:15:17Z
      DOI: 10.1016/j.livsci.2017.11.005
      Issue No: Vol. 207 (2017)
       
  • Differential level of oxidative stress markers in skin tissue of zebu and
           crossbreed cattle during thermal stress
    • Authors: Uttarani Maibam; O.K. Hooda; P.S. Sharma; R.C. Upadhyay; A.K. Mohanty
      Pages: 45 - 50
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): Uttarani Maibam, O.K. Hooda, P.S. Sharma, R.C. Upadhyay, A.K. Mohanty
      The study aimed to evaluate oxidative stress markers (ROS, GPx, GRx) in skin tissue of cattle with different coat colors during different seasons. Ten each of Tharparkar (zebu) and Karan Fries (crossbred) heifers were selected from NDRI herd, Karnal. Animals were maintained under standard managemental practices followed at the farm. Skin biopsies were aseptically collected from each animal during winter, spring and summer. ROS, GPx, GRx were determined by ELISA. Real time PCR was performed to examine the expression of skin color genes (MC1R and PMEL) in skin tissue. In both the breeds, significantly higher (P < 0.05) levels of ROS, GPx, GRx were observed during summer followed by winter and spring. Expression of MC1R and PMEL was increased during summer and winter than spring, but magnitude of expression was lower during summer than winter. ROS, GPx, GRx levels during summer were higher (P < 0.05) in Karan Fries than Tharparkar, whereas MC1R and PMEL expression levels were higher in Tharparker than Karan Fries. The study concluded that oxidative stress in skin tissue increased with heat stress in cattle, but the generation of oxidative stress due to heat stress was higher in lighter pigmented skin of Karan Fries than darker pigmented skin of Tharparkar. Higher expression of skin color genes in skin tissue of Tharparker (Bos indicus) might have induced greater pigmentation in them compared to crossbred (Bos indicus × Bos taurus)) cattle, thus increasing the skin protective capacity and reducing oxidative stress in them under heat stress. This might be a critically important factor for superior heat tolerance of zebu than crossbred cattle.

      PubDate: 2017-12-26T18:15:17Z
      DOI: 10.1016/j.livsci.2017.11.003
      Issue No: Vol. 207 (2017)
       
  • Copy number variation regions in Nellore cattle: Evidences of environment
           adaptation
    • Authors: Marcos Vinicius Antunes de Lemos; Mariana Piatto Berton; Gregório Miguel Ferreira de Camargo; Elisa Peripolli; Rafael Medeiros de Oliveira Silva; Bianca Ferreira Olivieri; Aline S.M. Cesar; Angélica Simone Cravo Pereira; Lucia Galvão de Albuquerque; Henrique Nunes de Oliveira; Humberto Tonhati; Fernando Baldi
      Pages: 51 - 58
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): Marcos Vinicius Antunes de Lemos, Mariana Piatto Berton, Gregório Miguel Ferreira de Camargo, Elisa Peripolli, Rafael Medeiros de Oliveira Silva, Bianca Ferreira Olivieri, Aline S.M. Cesar, Angélica Simone Cravo Pereira, Lucia Galvão de Albuquerque, Henrique Nunes de Oliveira, Humberto Tonhati, Fernando Baldi
      The aim of the present study was to analyze the distribution of CNV regions (CNVRs) as well as to address hypothesis about the natural/artificial selection process in Nellore cattle. A total of 399,361 CNVs were identified, using the PennCNV algorithm, in 3794 Nellore cattle (Bos taurus indicus) genotyped with the Bovine HD BeadChip array. The default quality control was applied and 2902 samples and 195,873 CNVs remained. The medium CNV length size was 54,744bp with a maximum of 870,000bp and a minimum of 3000bp. The CNVRs were generated by overlapping the 195,873 identified CNVs using the CNVRuler program. There was a higher incidence of CNVRs on BTA19 (24.26%), BTA23 (18.68%), and BTA25 (18.05%). The chromosomes that showed a lower incidence of CNVR were BTA29 (1.63%), BTA13 (9.72%), and BTA8 (9.72%). According to the type, 38.5%, 28.5% and 33.0% of the CNVRs were characterized as insertion, deletion and mixed (insertion and deletion in the same region), respectively. The 9805 CNVR estimated in the present study covered approximately 13.05% of the cattle genome (UMD_3.1, 2,649,685,063bp) and overlapped with 5495 genes. These genes have functions described as involved in biological processes that might be related to the environmental adaptation of the subspecies to tropical areas, such as regulation of vasodilatation, immune system response, hair follicle morphogenesis, among others. This study confirms the existence of large structural variations in the Nellore cattle genome and contributes to understanding the differences between cattle subspecies. Besides, it can also work as a guideline for future studies in which structural variations are present.

      PubDate: 2017-12-26T18:15:17Z
      DOI: 10.1016/j.livsci.2017.11.008
      Issue No: Vol. 207 (2017)
       
  • Supplementation of diets with omega-3 fatty acids from microalgae: Effects
           on sow reproductive performance and metabolic parameters
    • Authors: C.J.M. Posser; L.M. Almeida; F. Moreira; I. Bianchi; B.G. Gasperin; T. Lucia
      Pages: 59 - 62
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): C.J.M. Posser, L.M. Almeida, F. Moreira, I. Bianchi, B.G. Gasperin, T. Lucia
      Supplementation of diets with omega-3 polyunsaturated fatty acids (PUFA) may benefit sow reproductive performance, but the efficiency of algae as a source of PUFA is still unknown. This study evaluated serum levels of metabolic markers and reproductive performance of sows supplemented with the heterotrophic microalgae Schizochytium sp. Sows (n = 596) were supplemented from the 85th day of gestation, during lactation and until the weaning-estrous interval (WEI). Microalgae were included at five levels: 0 (control); 3.5; 7.0; 14.0; and 28.0g/d. Blood samples were collected at the 85th day of gestation, at the 10th d of lactation and at the last day prior to weaning (WEI). Serum levels of cholesterol, triglycerides, insulin-like growth factor type-1 (IGF-1) and non-esterified fatty acids (NEFA) were evaluated. At the parity concurrent with the supplementation, no effects were observed on stillborn rates (P > 0.05), sows fed 28.0g/d farrowed heavier piglets than sows fed lower levels (P < 0.05), but the WEI for sows fed 7.0g/d was longer than for the control (P < 0.05). Serum levels of triglycerides were decreased during gestation, only for sows supplemented with 14.0 and 28.0g/d (P < 0.05). At the subsequent parity, there was no difference on stillborn rates and total litter size (P > 0.05). The highest tested concentration (28.0g/d) of Schizochytium sp. was associated with reduced serum levels of triglycerides during gestation and with increased piglet birth weight, but the supplementation generally did not benefit sow reproductive performance.

      PubDate: 2017-12-26T18:15:17Z
      DOI: 10.1016/j.livsci.2017.11.006
      Issue No: Vol. 207 (2017)
       
  • The repeatability of individual nutrient digestibility in pigs
    • Authors: W. Ouweltjes; L.M.G. Verschuren; J. Pijlman; R. Bergsma; D. Schokker; E.F. Knol; P.J. van der Aar; F. Molist; M.P.L. Calus
      Pages: 63 - 67
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): W. Ouweltjes, L.M.G. Verschuren, J. Pijlman, R. Bergsma, D. Schokker, E.F. Knol, P.J. van der Aar, F. Molist, M.P.L. Calus
      Digestibility of nutrients in pig diets is an important component of overall feed efficiency. Targeted improvement of digestibility is currently mainly achieved by optimization of pig diets, based on information generated from digestibility trials that aim to establish fecal digestibility coefficients of different nutrients across a variety of ingredients. Genetic selection for nutrient digestibility is hampered by shortage of data on individual digestibility, but might help to further improve efficiency of pork production. The present study aimed to estimate the repeatability of fecal digestibility in pigs, as a first step to judge the perspectives for a breeding approach of nutrient digestibility. To achieve this, data was accumulated across nine digestibility trials, containing 1150 digestibility records of 416 growing pigs, measured across the trials. The data was analyzed with a model estimating variances for trial, diet, common litter, and individual animal effect for digestibility of Dry Matter, Ash, Organic Matter, Crude Protein, Crude fat and Non-Starch Polysaccharides. The factors diet and trial together explained the majority of the phenotypic variance, due to the design of the trials. Within diet and trial, common litter and individual animal effect contributed 0–10% of the phenotypic variance. The repeatability estimates ranged from 7% for Ash to 16% for Crude Protein, which suggests there may be genetic variation between pigs in digestibility. In conclusion, the repeatability estimates indicate it is worthwhile to collect phenotypic data that enable the estimation of genetic parameters for digestibility, if these data can be obtained at reasonable cost.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.013
      Issue No: Vol. 207 (2017)
       
  • Energy and protein requirements for maintenance of Southern Yellow cattle
           fed a corn silage or straw-based diet
    • Authors: M. Wei; L. Chen; X.M. Lian; Z.Q. Chen; P.S. Yan
      Pages: 75 - 82
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): M. Wei, L. Chen, X.M. Lian, Z.Q. Chen, P.S. Yan
      The objective of this study was to estimate the net energy and net protein requirements for maintenance (NEm and NPm) of Southern Yellow cattle in China. A database involving 175 cattle with body weight (BW) ranging from 211 to 454kg was obtained from a series of calorimetry experiments. The diets offered to cattle consisted of proportionately corn-soybean meal concentrate and roughage containing corn silage, rice straw and wheat straw. Linear regression equations of the logarithm of heat production (HP) and retained energy (RE) against metabolizable energy intake (MEI) were developed to predict the maintenance requirements for metabolizable energy (MEm) and NEm. The combined data indicated that the MEm and NEm were 522 and 348 MJ/kg0.75 of BWd−1, respectively. In addition, the partial efficiency of use of ME for maintenance was 0.66, and the partial efficiency for growth was 0.51. Similarly, there was also a linear relationship between retained nitrogen (RN) and nitrogen intake (NI). The pooled data provided a NPm of 2.63g/kg0.75 of BWd−1 and a metabolizable protein requirement for maintenance (MPm) of 3.93g/kg0.75 of BWd−1 for Southern Yellow cattle. In conclusion, our estimate of NEm was extremely similar to the value of the AFRC nutritional system, whereas it was slightly greater than that recommended by the NRC nutritional system. Additionally, the MPm value obtained in the current study was in agreement with the NRC recommendation.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.09.002
      Issue No: Vol. 207 (2017)
       
  • Effect of candidate genes for maternal ability on piglet survival and
           growth
    • Authors: E. Jonas; L. Rydhmer
      Pages: 83 - 90
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): E. Jonas, L. Rydhmer
      Our study aimed to test if genes related to maternal ability can be used as genetic markers to improve piglet production. We considered polymorphisms in the oxytocin gene and other loci related to metabolic oxytocin levels and maternal behavior. We hypothesized that genetic variants in these genes can be used to select sows with good mothering ability, expressed as the ability to raise many fast-growing piglets. We identified polymorphisms in candidate genes and used additional closely located known polymorphisms to genotype sows and to test the association of the polymorphisms. Nine genes, oxytocin (OXT), oxytocin receptor (OXTR), mesoderm-specific transcript (MEST), paternally expressed gene 3 (Peg3), growth factor receptor-bound substrate 10 (Grb10), FBJ murine osteosarcoma viral oncogene homolog B (FOSB), cluster of differentiation 38 (CD38), neurohypophyseal hormone arginine vasopressin (AVP) and protein kinase C, gamma (PRKCG) were selected for analysis. We identified four novel single nucleotide polymorphisms (SNP), while 23 SNP identified using sequencing were already reported in a public database. Sows were genotyped using SNP identified using sequencing and from a public database, and a total of 30 out of 65 SNP segregated in the population. We tested the association of 20 markers with traits from up to 164 sows, including number and weight of piglets born and weaned and growth rate of piglets until week 5. Polymorphisms in or close to genes FOSB, PRKCG, Grb10, OXTR, and AVP showed significant associations (after Bonferroni correction, P < 0.00256) with mean birth weight, piglets stillborn of total born and relative weight change of the sow during lactation. We identified some effects (P < 0.05) of SNP close to or within OXT, MEST, FOSB, AVP and PRKCG on number of piglets dead or stillborn from total or live born. Birth weight and piglet growth were slightly (P < 0.05) influenced by polymorphisms in or close to genes Grb10, Peg3 and PRKCG. Two markers in the regions of genes MEST and Grb10 showed an effect (P < 0.05) on the relative fat and weight change of the sow during lactation, respectively. Most of the associations were either identified in the first or second parity, indicating strong differences between the traits across these early parities. Future studies should investigate the correlation between maternal behavior traits and the traits investigated here and test the effect of the investigated loci on behavior in sows. If these genes are associated with favorable maternal behaviors in pigs and if they are useful indicators of the maternal ability, they could be used to identify sows with high genetic ability to raise many fast growing piglets. Implications The survival of piglets is one important measure of successful pig production and the sow plays a major role for the survival of piglets. Selection of maternal lines focusses on maternal ability as it is relevant for piglet survival. We found some associations between candidate gene markers and maternal ability traits. But since the associations were not consistent from the first to the second parity, the markers seem to be less valuable for breeding.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.018
      Issue No: Vol. 207 (2017)
       
  • Effect of wheat as a feedstuff in starter diets on nursery pig growth
           performance and digestibility
    • Authors: D.J. Bloxham; C.R. Dove; M. Azain
      Pages: 98 - 104
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): D.J. Bloxham, C.R. Dove, M. Azain
      Two studies were conducted to determine if corn can be replaced by wheat and if wheat can be combined with corn distillers dried grains with solubles (DDGS) and a commercial carbohydrase in phase 2 and 3 nursery diets. In Exp. 1, 144 pigs were blocked by weight and randomly allotted to 6 dietary treatments: 0%, 20%, 40%, 60%, 80%, and 100% wheat replacing corn. In Exp. 2, 210 pigs were blocked by weight and randomly allotted to 5 dietary treatments: control diet (CO); 30% wheat (W); wheat with carbohydrase (W + Enz); 30% wheat with 30% corn DDGS (WCD); and WCD with carbohydrase (WCD + Enz). In both experiments, pigs were fed a standard phase 1 diet from d 0 to 7 post-weaning. In both experiments, TiO2 was used as an indigestible marker to determine apparent total tract digestibility (ATTD) of N, ether extract (EE), gross energy (GE), P, neutral detergent fiber (NDF), and acid detergent fiber (ADF). In Exp. 1, there was a quadratic effect of increasing wheat on overall (d 0–35) average daily gain (ADG, P < 0.05). There was a linear effect of increasing wheat on gain to feed ratio (G:F, P < 0.05). Overall there were no changes in average daily feed intake (ADFI). Apparent digestibility of N, P, and ADF increased with increasing wheat in phase 2 (P < 0.05). The digestibility of N, EE, GE, P, and NDF increased linearly with increasing wheat in phase 3 (P < 0.05). In Exp. 2, the ADG of pigs fed W did not differ from the control, while those fed WCD had greater gain (P < 0.05). Pigs fed the diets supplemented with carbohydrase had reduced ADG (P < 0.05) compared to the unsupplemented diets. There was an increase in N, P, and GE digestibility with DDGS diets in phase 2 (P < 0.001). Carbohydrase supplementation increased N, EE, ADF, and NDF digestibility in phase 2 (P < 0.01), and ADF and NDF digestibility in phase 3 (P < 0.01). In phase 3, P digestibility increased and GE digestibility decreased when DDGS was added. The results demonstrate that wheat can be fully or partially substituted for corn in nursery diets. In this study, the addition of carbohydrase enzymes improved nutrient digestibility, but resulted in poorer growth performance.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.016
      Issue No: Vol. 207 (2017)
       
  • Gastrointestinal microbial diversity and short-chain fatty acid production
           in pigs fed different fibrous diets with or without cell wall-degrading
           enzyme supplementation
    • Authors: Y.J. Zhang; Q. Liu; W.M. Zhang; Z.J. Zhang; W.L. Wang; S. Zhuang
      Pages: 105 - 116
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): Y.J. Zhang, Q. Liu, W.M. Zhang, Z.J. Zhang, W.L. Wang, S. Zhuang
      The microbial diversity and short-chain fatty acid (SCFA) production in pigs fed different fibrous diets with or without cell wall-degrading enzyme (phytase, cellulase and xylanase) supplementation were compared using the Illumina MiSeq sequencing technique. Eight growing castrated pigs fitted with a T-shaped cannula at the terminal ileum were randomly assigned to four diets, i.e., wheat bran-based diet (WB), enzyme-supplemented WB, soybean hull-based diet (SH), and enzyme-supplemented SH, according to a 4 × 4 Latin square design. The ileal digesta and feces were collected after 15 days of adaptation in each period. The WB diet increased (P < 0.05) the abundances of Lactobacillus, Veillonella and Ruminococcaceae compared to SH diet, whereas the SH diet led to a higher (P < 0.05) abundances of Streptococcaceae, Peptostreptococcaceae, Lachnospiraceae, Treponema and Methanobrevibacter than that of WB diet. Adding exogenous cell wall-degrading enzyme selectively altered the relative abundance of bacteria in both dietary groups. The SH promoted (P < 0.01) the concentrations of acetate, propionate and total SCFA in the ileal digesta and feces, and enzyme supplementation led to similar results for SCFA production (P < 0.01) but not for acetate in the feces compared to that of WB. These results may provide valuable information on how to utilize fibrous feedstuffs efficiently in animal production.
      Graphical abstract image

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.017
      Issue No: Vol. 207 (2017)
       
  • Culling vs. emergency vaccination: A comparative economic evaluation of
           strategies for controlling classical swine fever in the EU
    • Authors: Verena Otter; Maria Näther; Ludwig Theuvsen
      Pages: 133 - 146
      Abstract: Publication date: January 2018
      Source:Livestock Science, Volume 207
      Author(s): Verena Otter, Maria Näther, Ludwig Theuvsen
      Outbreaks of epidemic animal diseases, especially classical swine fever (CSF), are associated with high costs for livestock-producing regions like the European Union (EU). Alternative and complimentary measures exist for dealing with epidemics of animal diseases such as CSF: culling, quarantine, emergency vaccination, preventive vaccination and disease monitoring. In the EU culling in combination with quarantine has remained the only strategy to handle CSF outbreaks. Due to member states’ concerns about the tradability of vaccinated pigs and products from vaccinated animals, recent EU decisions have not considered emergency vaccination an appropriate alternative measure although modern DIVA vaccines allow the distinction between infected and vaccinated animals. Concurrently, the potential contribution of DIVA vaccines to the reduction of economic damages of CSF outbreaks has not been thoroughly addressed so far. This research gap motivates to compare the costs of culling and emergency vaccination for the latest outbreak of CSF in the EU exemplarily by applying a self-developed comprehensive simulation tool (TEUS) on the 2006 CSF epidemic in Germany. The results reveal that emergency vaccination involves lower direct costs but higher indirect costs than culling. Especially political interventions by the European Commission, the governments of its member states and the governments of non-EU member states are considered to make an emergency vaccination in case of an CSF outbreak economically unattractive under current conditions. This outcome implies the request for more emergency vaccination friendly EU regulations and OIE requirements.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.014
      Issue No: Vol. 207 (2017)
       
  • Application of natural wax markers in equine nutrition studies – current
           state, limitations and perspectives
    • Authors: Martin Bachmann; Johannes Hepp; Michael Zech; Michael Bulang; Annette Zeyner
      Abstract: Publication date: Available online 20 December 2017
      Source:Livestock Science
      Author(s): Martin Bachmann, Johannes Hepp, Michael Zech, Michael Bulang, Annette Zeyner
      The basis of a successful assessment of the nutritive value of feeds and an animal's supply with dietary energy and nutrients is having sufficient knowledge on key indicators such as feed intake, diet composition, digestibility and the kinetics of gut passage. In horses and other equids, the determination of such indicators is impractical outside controlled conditions, particularly in pasture-based husbandry. Natural wax components such as n-alkanes, alkenes, primary alcohols and fatty acids might be beneficial estimators, but their application is limited in practice. This review provides a concise view into the application of plant wax components, especially alkanes and their external counterparts, in equine nutrition studies. Recent methodological developments and the current state of knowledge are summarized as an interim conclusion. Methodological limitations still hamper an easy application of the method, and some perspectives for future methodological research are discussed. Conclusively, little information is available on feed plant concentrations and variations of primary alcohols, fatty acids and alkenes, and their natural carbon isotope (13C/12C) ratios. Moreover, the magnitude and the (in)consistency of faecal recovery of these markers is barely described. Methodological research should continue focusing on an effective application of plant markers. In horses, especially plant marker-based methods for the estimation of diet composition and passage kinetics will require much more consideration.

      PubDate: 2017-12-26T18:15:17Z
      DOI: 10.1016/j.livsci.2017.12.010
       
  • Detoxification of aflatoxin B1 by lactic acid bacteria and hydrated sodium
           calcium aluminosilicate in broiler chickens
    • Authors: Ning Liu; Jinquan Wang; Qingqing Deng; Kuntao Gu; Jianping Wang
      Abstract: Publication date: Available online 10 December 2017
      Source:Livestock Science
      Author(s): Ning Liu, Jinquan Wang, Qingqing Deng, Kuntao Gu, Jianping Wang
      Aflatoxin contamination is very common in feedstuffs across the world and finding an ideal detoxifier is urgent because of the toxic action on animals and negative effects on foods, humans, and the environment. To thoroughly eliminate the toxin, a detoxification method has changed from physical to biological. The objective of the present study was to investigate the effect of lactic acid bacteria (LAB) and hydrated sodium calcium aluminosilicate (HSCAS) on detoxification of aflatoxin B1 (AFB1) by assessing growth performance, digestibility, immune function, and AFB1 residues in tissues and excreta of broiler chickens from d 0 to 21. A total of 480 female broiler chicks on d 0 were randomly allotted to 4 treatments with 6 cages of 20 chicks each for diets: positive control (PC, undetectable AFB1), negative control (NC, PC + 40µg AFB1/kg), LAB (NC + 1.5 × 1010 cfu LAB/kg), and HSCAS (NC + 3.0g HSCAS/kg). Results showed that the NC treatment reduced (P < 0.05) average daily gain and feed efficiency, and LAB or HSCAS supplementation improved (P < 0.05) the growth performance of broiler chickens, and the effect of LAB was greater than HSCAS. The LAB and HSCAS increased (P < 0.05) the digestibility of dry matter, crude protein, crude fat, and digestible energy by 4.0 to 15.0%, and improved (P < 0.05) immune function by modulating the relative weights of immune organs, lymphocyte percentages, and immunoglobulin contents. Additionally, residual AFB1 in serum and organs in LAB treatment was lower (P < 0.05) than HSCAS. The results indicate that LAB and HSCAS can detoxify AFB1 in the diet of broiler chickens, and LAB is more effective than HSCAS in partial biodegradation of AFB1.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.12.005
       
  • Meat and fat quality traits of grazing steers supplemented with corn grain
           and increasing amounts of flaxseed
    • Authors: M.M. Della Rosa; L.B. Pouzo; E. Pavan
      Abstract: Publication date: Available online 7 December 2017
      Source:Livestock Science
      Author(s): M.M. Della Rosa, L.B. Pouzo, E. Pavan
      To evaluate the effect of corn and flaxseed supplementation at finishing on longissimus thoracis color and shear-force and on subcutaneous fat color, forty-eight angus steers were assigned to four dietary treatments (DIET): no-supplement, supplemented with 0.7% live weight (LW) of cracked corn grain plus 0.0%, 0.125% and 0.25% LW of whole flaxseed in two finishing trials (Trial-1, early spring and Trial-2, late spring). None of the evaluated variables were affected by DIET in either trial, nor in a combined statistical analysis of the pooled data. The lack of DIET effect observed on muscle color and shear-force, are in agreement with the similar longissimus muscle pH@45min, temp@45min, pH@24h, and glycogen content at slaughter observed between DIET. Lack of shear force difference between supplementation treatments is in agreement with their similar muscle sarcomere length, total and soluble collagen content and proportion of intact troponin-T. Subcutaneous fat color was also similar between supplementation treatments. Corn or flaxseed supplementation of steers grazing a high-quality pasture did not improve meat or subcutaneous fat color and meat shear force.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.12.004
       
  • Impacts of using a precision livestock system targeted approach in
           mountain sheep flocks
    • Authors: Claire Morgan-Davies; Nicola Lambe; Harriet Wishart; Tony Waterhouse; Fiona Kenyon; Dave McBean; Davy McCracken
      Abstract: Publication date: Available online 5 December 2017
      Source:Livestock Science
      Author(s): Claire Morgan-Davies, Nicola Lambe, Harriet Wishart, Tony Waterhouse, Fiona Kenyon, Dave McBean, Davy McCracken
      Although mountain sheep systems suffer from climatic and environmental handicaps that constrain productivity and economic viability, they have an important economic role, maintain habitats and species of high nature conservation value and support the provision of a range of ecosystem services of benefit to society. Using Precision Livestock Farming (PLF) in extensive mountain sheep systems could bring benefits for animal performance, economical performance and labour. This paper presents results from a 3 year experiment where PLF principles were implemented on an extensive mountain sheep farm and an assessment made of whether or not such an approach could benefit more marginal sheep systems. A 900 ewe flock (600 Scottish Blackface ewes, 300 Lleyn ewes) was divided equally into two separate systems, one where the flock was managed conventionally (CON) at group level, and the other where the individuals in the flock were subjected to a PLF management protocol where electronic weighing, recording and drafting equipment were used, linked to the electronic identification (EID) tags of the animals. Two main management strategies were compared and contrasted; one relating to winter feeding of the pregnant ewes, the other relating to anthelmintic treatment of lambs during the summer. Yearly labour profiles were created by measuring the time spent doing individual tasks associated with the two management systems. Net margins (£/ewe) were calculated for the two systems. Additionally, the yearly labour profiles were scaled-up using commercial data to quantify potential labour savings on more traditionally managed mountain farms if PLF principles were adopted. Analyses indicated that the two different management systems did not result in any significant difference in terms of ewe weights, mid-pregnancy scanning figures, ewe and lamb mortality rates, or lamb weight post-weaning. However, the proportion of lambs needing anthelmintic treatment was significantly reduced by 40% between the CON and the PLF, resulting in a reduction of 46% in the amount of anthelmintic used. Over a whole year, the total amount of labour required in the PLF management system was reduced by 36%. Across the 3 years, the net margin for the two systems showed an average difference of £3/ewe higher in the PLF. For a more traditional farm embracing a PLF approach, analyses suggested labour reduction of 19%, equating to £1.60/ewe savings. This study shows that it is beneficial for farmers to consider managing a mountain ewe flock at an individual rather than at flock or batch level using PLF technology.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.12.002
       
  • New genes involved in the Bacterial Chondronecrosis with Osteomyelitis in
           commercial broilers
    • Authors: Bruna Petry; Igor Ricardo Savoldi; Adriana Mércia Guaratini Ibelli; Ediane Paludo; Jane de Oliveira Peixoto; Fátima Regina Ferreira Jaenisch; Diego de Córdova Cucco; Mônica Corrêa Ledur
      Abstract: Publication date: Available online 5 December 2017
      Source:Livestock Science
      Author(s): Bruna Petry, Igor Ricardo Savoldi, Adriana Mércia Guaratini Ibelli, Ediane Paludo, Jane de Oliveira Peixoto, Fátima Regina Ferreira Jaenisch, Diego de Córdova Cucco, Mônica Corrêa Ledur
      Locomotor problems have a great economic impact on world poultry production, because difficulty of locomotion leads to a decrease in animal performance and an increase in partial or total carcass condemnation. In addition, locomotor problems greatly affect the chicken welfare. Bacterial Chondronecrosis with Osteomyelitis (BCO) or Femoral Head Necrosis (FHN) is responsible for altering the bone tissue degenerating the cartilage and femoral epiphysis. Despite its not well known etiology, it is believed that this disorder causes a decrease in tissue vascularization, interfering with blood flow and affecting the angiogenesis processes, predisposing broilers to bone problems. Genetic factors associated to rapid growth rate of the modern broilers are pointed out as predisposing chickens to BCO. Therefore, the aim of this study was to evaluate the expression of 13 functional candidate genes in femur samples of normal and BCO-affected commercial broilers at 35 days of age to clarify the genetic mechanisms involved in the BCO in chickens. From the 13 genes studied, 10 were differentially expressed (DE) between groups: ADIPOQ, PRRX1, ANGPTL5, GFRA2, SFRP5, COL14A1, ABI3BP, ANGPTL7, COL8A1 and SLC30A10, which were downregulated in broilers affected by BCO, except for the SLC30A10, which was upregulated in the affected chickens. Although their functions are not well established in chickens, these genes participate in important biological processes in mammals, such as osteogenesis, formation of connective tissue and collagen production, and general bone development. The genes expression pattern, their functions and interactions, altogether, pointed out those DE genes as strong candidates to be involved with BCO in broiler chickens. The DE genes evaluated in this study might contribute to tissue necrosis, which could lead to the development of bacterial chondronecrosis with osteomyelitis in chickens. Those should be further investigated aiming to reduce this bone anomaly in broilers.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.12.003
       
  • Changes in the vaginal microbiota in ewes after insertion of intravaginal
           sponges at different stages of the oestrous cycle
    • Authors: Jorgelina Manes; María A. Fiorentino; Silvina San Martino; Rodolfo Ungerfeld
      Abstract: Publication date: Available online 5 December 2017
      Source:Livestock Science
      Author(s): Jorgelina Manes, María A. Fiorentino, Silvina San Martino, Rodolfo Ungerfeld
      The aims of this study were to determine if the ewe’ vaginal bacterial load differs according to the stage of the oestrous cycle; and thus, if the stage of the oestrous cycle when intravaginal sponges (IS) used for oestrous synchronisation are inserted influences the vaginal bacterial biota present at sponge withdrawal. During the breeding season, 45 Texel ewes were detected in oestrus and randomly allocated to one of three treatments of 15 ewes each according to the stage of the oestrous cycle when the IS were inserted. Intravaginal sponges were inserted: the day of oestrus (GOes), or 2 (GMet) or 8 (GDie) days after oestrus. Samples for bacterial analysis were collected the day of IS insertion (Day 0), at sponge withdrawal (Day 12), 24h (Day 13) and 48h (Day 14) after sponge withdrawal. Vaginal bacteria amount increased at sponge withdrawal in all treatment (p<0.0001). The number of different types of colonies was greater in GMet group than in GDie at sponge insertion (p<0.05), without difference with GOes. At sponge insertion, the presence of Staphylococcus spp. was greater in GMet than in GOe and GDi (p<0.05); the presence of Trueperella pyogenes and Haemophilus somni was greater after sponge withdrawal than before sponge insertion (p<0.001), but without difference between days 12, 13 and 14. Overall, we concluded that in ewes the normal vaginal bacterial load differs according to the stage of the oestrous cycle. The continuous presence of the IS homogenised the vaginal bacterial microbiota at withdrawal, with only slight and transient differences observed on day 13.

      PubDate: 2017-12-12T02:37:36Z
      DOI: 10.1016/j.livsci.2017.11.023
       
  • Genetic and Phenotypic Parameters for Feed Efficiency in Indigenous
           Chicken in Kenya
    • Authors: Sophie Miyumo; Chrilukovian B. Wasike; Alexander K. Kahi
      Abstract: Publication date: Available online 10 November 2017
      Source:Livestock Science
      Author(s): Sophie Miyumo, Chrilukovian B. Wasike, Alexander K. Kahi
      This study aims to determine the genetic and phenotypic parameters of net feed efficiency (NFE) traits namely Residual feed intake (RFI), residual gain (RG), and residual intake and gain (RIG) along the growth curve of indigenous chicken in Kenya. Feed intake and body weight data was collected on 107 experimental birds on a daily and weekly basis, respectively from 77 days to 140 days of age. Random regression sire model was used for analysis, fitting Legendre polynomials as basis function. Sex, hatch group and interaction between sex and cluster constituted fixed effects in the model while additive genetic and permanent environmental effects were fitted as random variables. A heteroscedastic residual variance was modelled by grouping the test period into nine classes. The orders of polynomial fit for additive genetic and permanent environmental effects in the model were 4 and 5; 3 and 4; and 5 and 5; for RFI, RG and RIG, respectively. The additive genetic variances for RFI and RG were higher at the beginning of the trajectory but declined as the test period progressed while their respective phenotypic and permanent environment variances increased with age. Consequently, moderate (0.34) and high (0.77) heritability estimates for RFI and RG, respectively, were observed during the early test period and thereafter decreased to 0.03 for RFI and 0.01 for RG. Additive genetic variance for RIG increased across the test period while phenotypic and permanent environment variances declined. This resulted in high estimates of heritability and permanent environmental variance as a proportion of phenotypic variance of 0.69 and 0.98, respectively, at the extremes of the trajectory. At mid-point of test period, low estimates of heritability and permanent environmental variance as a proportion of phenotypic variance of 0.13 and 0.19, respectively were observed. The heritability estimates indicate possible selective breeding for NFE given the moderate estimates (0.23 to 0.34) for RFI, moderate to high estimates (0.30 to 0.77) for RG and high estimates (0.49 to 0.98) for RIG. However, caution has to be taken when selecting for RG and RIG given the extreme heritability estimates resulting from statistical and biological factors. Genetic correlations were high to moderate and positive (0.99 to 0.32) between records at early and mid-ages (77 to 105 days), but high and negative (−0.99 to −0.45) between early (77 days) and late ages (112 to 140 days). Selection for NFE at growth inflection point (77 days) would result in a favourable correlated response at point of maximum growth (105 days) but would be associated with unfavourable response at point of asymptotic growth (140 days) as birds are approaching sexual maturity. Given the high standard errors for the genetic parameters estimates in this study, there is need for further analyses prior to selection for feed efficiency indigenous chicken.

      PubDate: 2017-11-16T08:33:47Z
      DOI: 10.1016/j.livsci.2017.11.011
       
  • Impact of breed on the rumen microbial community composition and methane
           emission of Holstein Friesian and Belgian Blue heifers
    • Authors: Thijs De Mulder; Nico Peiren; Leen Vandaele; Tom Ruttink; Sam De Campeneere; Tom Van de Wiele; Karen Goossens
      Abstract: Publication date: Available online 8 November 2017
      Source:Livestock Science
      Author(s): Thijs De Mulder, Nico Peiren, Leen Vandaele, Tom Ruttink, Sam De Campeneere, Tom Van de Wiele, Karen Goossens
      Intensive dairy and beef cattle farming contribute significantly to the emissions of greenhouse gases from Belgian agriculture. Two main breeds dominate the Belgian cattle livestock; Holstein-Friesian (HF) dairy cattle and double-muscled Belgian Blue (DMBB) beef cattle. The aim of our study was to quantify and compare methane emissions of both breeds under conditions of equal diet composition, environment and physiological stage (using heifers of the same age). The methanogen and bacterial communities were thoroughly investigated using metabarcoding to correlate taxonomic compositions with breed and methane emission levels. HF heifers had significantly higher absolute enteric methane emissions as compared to DMBB heifers. Methane production was positively correlated to the dry matter intake (DMI). Due to the significantly higher DMI and energy intake of HF heifers, methane yield per DMI was not significantly different between breeds. Furthermore, no significant differences were observed between the gross feed efficiency (GFE) of both breeds, but the DMBB heifers demonstrated significantly lower CH4:CO2 ratios (mole-to-mole ratio), suggesting a more efficient fermentation by the rumen microbial ecosystem. Although both breeds accommodated a common core of taxonomic groups, the bacterial communities also showed a breed specific composition due to differential abundance of specific species belonging to the main taxonomic groups and the presence of a few species of minor taxonomic groups that were significantly associated with one of both breeds. In contrast to the bacterial communities, the methanogen community was consistent and stable between breeds and at different sampling times. Our results suggest that breed related factors influence the bacterial community composition, while the variation in methane emission levels can be attributed mainly to the feed intake of the animals.
      Graphical abstract image

      PubDate: 2017-11-09T02:21:19Z
      DOI: 10.1016/j.livsci.2017.11.009
       
  • MicroRNA expression patterns in tail fat of different breeds of sheep
    • Authors: Yangyang Pan; Jiongjie Jing; Junxing Zhao; Xiali Jia; Liying Qiao; Lixia An; Baojun Li; Yuan Ma; Yingjiao Zhang; Wenzhong Liu
      Abstract: Publication date: Available online 6 November 2017
      Source:Livestock Science
      Author(s): Yangyang Pan, Jiongjie Jing, Junxing Zhao, Xiali Jia, Liying Qiao, Lixia An, Baojun Li, Yuan Ma, Yingjiao Zhang, Wenzhong Liu
      The objective of this study was to detect the expression profile of microRNAs (miRNAs) in two breeds of fat-tailed sheep (Guangling Large-tailed sheep and Small-tailed Han sheep), and discover the miRNAs that may play roles in lipid metabolism. Consequently, two small RNA libraries were constructed and high-throughput sequencing was used to identify the miRNAs expressed in the two libraries and to calculate the expression of miRNAs. Bioinformatics methods were used to predict target genes, which were subsequently analyzed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG). Nine miRNAs (miR-10b, miR-29a, miR-30c, miR-155, miR-192, miR-206, novel-miR-102, novel-miR-36, and novel-miR-63) were chosen to verify the sequencing results by detecting their expressions in the two breeds using quantitative real-time PCR. A total of 113 and 131 conserved miRNAs in the two breeds were obtained, of which 40 miRNAs were differentially expressed. KEGG analysis showed that many predicted target genes for these miRNAs are involved in lipid metabolism pathways. By screening the unknown miRNAs using MIREAP, 208 and 215 novel miRNAs were obtained from the two libraries, of which 150 were significantly different. This study represents the comprehensive survey of miRNAs expressed in the tail fat of two breeds of sheep with different tail fat deposition using HiSeq analysis. We conclude that differentially expressed miRNAs may play roles in regulating adipose metabolism, and thus, may contribute to improving the meat quality and fat deposition in sheep.

      PubDate: 2017-11-09T02:21:19Z
      DOI: 10.1016/j.livsci.2017.11.007
       
 
 
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