Guy Sarita Zhe Ying, Li Li, Thomson Peter Campbell, Hermesch Susanne
School of Life and Environmental Sciences, University of Sydney, Camden, New South Wales, Australia.
Animal Genetics and Breeding Unit, a joint venture of NSW Department of Primary Industries and University of New England, University of New England, Armidale, New South Wales, Australia.
J Anim Breed Genet. 2019 May;136(3):153-167. doi: 10.1111/jbg.12388. Epub 2019 Mar 15.
Contemporary group (CG) estimates of different phenotypes have not been widely explored for pigs. The objective of this study was to extend the traits used to derive environmental descriptors of the growing pig, to include CG estimates of early growth between birth and start of feed intake test (EADG), growth during feed intake test (TADG), lifetime growth (ADG), daily feed intake (DFI), backfat (BF) and muscle depth (MD). Pedigree and performance records (n = 7,746) from a commercial Australian piggery were used to derive environmental descriptors based on CG estimates of these six traits. The CG estimates of growth traits described different aspects of the environment from the CG estimates of carcass traits (r < 0.10). These definitions of the environment then were used in reaction norm analysis of growth, to evaluate sire-by-environment interaction (Sire × E) for growth. The most appropriate reaction norm model to evaluate Sire × E for growth was dependent on the environmental descriptor used. If the trait used to derive an environmental descriptor was distinctly different from growth (e.g., BF and MD), CG as an additional random effect was required in the model. If not included, inflated common litter effect and sire intercept variance suggest there was unaccounted environmental variability. There was no significant Sire × E using any of the definitions of the environment, with estimated variance in sire slopes largest when environments were defined by BF ( = 97 ± 83 (g/day) ), followed by environments defined by DFI ( = 39 ± 101 (g/day) ). While there appears to be differences in ability to detect Sire × E, improved data structure is required to better assess these environmental descriptors based on alternative traits. The ideal trait, or combination of traits, used to derive environmental descriptors may be unique for individual herds. Therefore, multiple phenotypes should be further explored for the evaluation of Sire × E for growth in the pig.
当代群体（CG）对猪不同表型的估计尚未得到广泛研究。本研究的目的是扩展用于推导生长猪环境描述符的性状，将出生至采食量测试开始之间的早期生长（EADG）、采食量测试期间的生长（TADG）、终生生长（ADG）、日采食量（DFI）、背膘厚（BF）和肌肉深度（MD）的CG估计值纳入其中。利用澳大利亚一家商业养猪场的系谱和性能记录（n = 7,746），基于这六个性状的CG估计值推导环境描述符。生长性状的CG估计值与胴体性状的CG估计值描述了不同方面的环境（r < 0.10）。然后将这些环境定义用于生长的反应规范分析，以评估生长的父本×环境互作（Sire×E）。评估生长的Sire×E最合适的反应规范模型取决于所使用的环境描述符。如果用于推导环境描述符的性状与生长明显不同（例如BF和MD），则模型中需要将CG作为额外的随机效应。如果不包括这一点，共同窝效应和父本截距方差膨胀表明存在未解释的环境变异性。使用任何环境定义均未发现显著的Sire×E，当环境由BF定义时，父本斜率的估计方差最大（ = 97 ± 83（g/天）），其次是由DFI定义的环境（ = 39 ± 101（g/天））。虽然在检测Sire×E的能力上似乎存在差异，但需要改进数据结构，以便根据替代性状更好地评估这些环境描述符。用于推导环境描述符的理想性状或性状组合可能因个体猪群而异。因此，应进一步探索多种表型，以评估猪生长的Sire×E。
