Pig Research Centre, Danish Agriculture & Food Council, Axelborg, Axeltorv 3, DK-1609 Copenhagen V, Denmark.
J Anim Sci. 2013 Apr;91(4):1562-9. doi: 10.2527/jas.2012-5584. Epub 2013 Feb 13.
This study aimed to estimate genetic parameters for the mortality causes stillborn, weak at birth, starvation, crushing, and miscellaneous in crossbred piglets produced by crossbred dams. Data were collected in a single Danish commercial herd from October 2006 to July 2008 and consisted of 34,194 piglets (2,152 litters), which originated from 195 Danish Duroc sires and 955 crossbreds between Danish Landrace and Danish Yorkshire dams. Of the 34,194 piglets born, 11.5% were stillborn, 4.2% were crushed by the sow, 2.7% died due to starvation, 2.3% were weak at birth, and 2.2% died of miscellaneous causes before weaning. The first 4 mentioned causes were analyzed multivariately using a generalized linear mixed model with a probit link function, including the genetic effect of both sire and dam. Heritabilities based on the sire component ranged between 0.08 for stillborn and 0.21 for starvation whereas heritabilities based on the dam component ranged between 0.01 for miscellaneous and 0.24 for stillborn, indicating that reducing piglet mortality through genetic selection is possible. The expected observed responses to selection would, however, be low. The genetic correlations between mortality traits based on the sire component ranged from -0.05 between stillborn and starvation to 0.35 between stillborn and weak at birth whereas genetic correlations based on the dam component ranged from -0.11 between weak at birth and starvation to 0.76 between crushing and starvation. There seemed to be a favorable relationship between the 2 traits stillborn and weak at birth and between crushing and starvation, implying that care should be taken with correct recordings of mortality causes. The genetic correlation precision was rather low, and if nonadditive effects are not accounted for, there may be unexpected correlated responses among the different mortality causes in the crossbred mortalities.
本研究旨在估计杂种母猪所产仔猪的死亡原因（死产、出生弱仔、饥饿、压死和其他原因）的遗传参数。数据来自于 2006 年 10 月至 2008 年 7 月丹麦的一个单一商业猪场，包括 34194 头仔猪（2152 窝），其来自 195 头丹麦杜洛克公猪和 955 头丹麦长白猪和丹麦大约克夏母猪的杂交后代。在出生的 34194 头仔猪中，11.5%为死产，4.2%被母猪压死，2.7%因饥饿死亡，2.3%出生时较弱，2.2%在断奶前死于其他原因。前 4 种原因采用包含公猪和母猪遗传效应的广义线性混合模型进行多元分析。基于公猪的遗传力范围从死产的 0.08 到饥饿的 0.21，而基于母猪的遗传力范围从其他原因的 0.01 到死产的 0.24，表明通过遗传选择降低仔猪死亡率是可能的。然而，选择的预期观察反应将很低。基于公猪的遗传相关性范围从死产和饥饿之间的-0.05 到死产和出生弱仔之间的 0.35，而基于母猪的遗传相关性范围从出生弱仔和饥饿之间的-0.11 到压死和饥饿之间的 0.76。死产和出生弱仔以及压死和饥饿之间似乎存在有利的关系，这意味着在记录死亡率原因时应小心。遗传相关性精度相当低，如果不考虑非加性效应，则杂种死亡率的不同死亡原因之间可能会出现意外的相关反应。
