Vallée A, Breider I, van Arendonk J A M, Bovenhuis H
J Anim Sci. 2015 Sep;93(9):4277-84. doi: 10.2527/jas.2015-9292.
In the last decades, beef cattle breeding mainly focused on improving production and reproduction traits. Nowadays, there is a growing interest to include behavior and type traits in the breeding goal. There is an interest in behavior as it is associated with human safety and workability and in type traits as they might be associated with longevity of cows. The objective of the current study was to estimate the heritability for behavior and type traits in Charolais and to estimate the genetic correlations among these traits. Behavior traits, including aggressiveness at parturition, aggressiveness during gestation period, and maternal care, were scored by farmers using an on-farm recording system to enable large-scale collection of phenotypes. Type traits, including udder traits ( = 3), teat traits (3), feet and leg traits (5), and locomotion (1), were scored by 10 trained classifiers. Data was available on 6,649 cows in parity 1 to 12 and located in 380 herds. Results showed that differences between herds explained up to 23% of the total phenotypic variance in behavior traits. This might be due to differences in management or to consistent differences in scoring between farmers. Aggressiveness at parturition had higher heritability (0.19) and higher genetic coefficient of variation (CV = 11%) than aggressiveness during gestation ( = 0.06 and CV = 4%) and maternal care ( = 0.02 and CV = 2%). Heritabilities for udder traits (0.14 to 0.20) and teat traits (0.17 to 0.35) were higher than for feet and leg traits (0.02 to 0.19). Genetic coefficients of variation for udder and teat traits were also higher (up to 21%) than for feet and leg traits (up to 11%). Strong genetic correlations were found between behavior traits (with absolute values from 0.71 to 0.98). The genetic correlations indicate that it is difficulty to simultaneously improve maternal care and reduce aggressiveness. We concluded that there are good opportunities to implement selection for improved udder and teat traits and against aggressiveness at parturition using a simple on-farm recording system of behavior.
在过去几十年里，肉牛育种主要侧重于提高生产和繁殖性状。如今，人们越来越有兴趣将行为和体型性状纳入育种目标。对行为性状感兴趣是因为它与人类安全和可操作性相关，对体型性状感兴趣是因为它们可能与奶牛的长寿有关。本研究的目的是估计夏洛莱牛行为和体型性状的遗传力，并估计这些性状之间的遗传相关性。行为性状，包括分娩时的攻击性、妊娠期的攻击性和母性关怀，由农民使用农场记录系统进行评分，以便大规模收集表型数据。体型性状，包括乳房性状（=3）、乳头性状（3）、蹄腿性状（5）和运动能力（1），由10名经过培训的分级员进行评分。数据来自380个牛群中处于第1至12胎次的6649头奶牛。结果表明，牛群间差异解释了行为性状总表型变异的23%。这可能是由于管理差异或农民评分的持续差异所致。分娩时的攻击性比妊娠期的攻击性（=0.06，变异系数=4%）和母性关怀（=0.02，变异系数=2%）具有更高的遗传力（0.19）和更高的遗传变异系数（变异系数=11%）。乳房性状（0.14至0.20）和乳头性状（0.17至0.35）的遗传力高于蹄腿性状（0.02至0.19）。乳房和乳头性状的遗传变异系数也高于蹄腿性状（高达11%）。行为性状之间发现了很强的遗传相关性（绝对值从0.71到0.98）。遗传相关性表明，同时改善母性关怀和降低攻击性很困难。我们得出结论，利用简单的农场行为记录系统，有很好的机会实施针对改善乳房和乳头性状以及反对分娩时攻击性的选择。
