Trail J C, Gregory K E, Marples H J, Kakonge J
J Anim Sci. 1982 Mar;54(3):517-23. doi: 10.2527/jas1982.543517x.
Data on 202 calves born, 191 calves weaned and 182 calves at 30 mo of age produced in 1969 from the Boran and Red Poll breeds and their reciprocal crosses were analyzed to estimate heterosis, additive maternal effects and additive direct effects on survival and growth traits from birth to 30 mo of age. The calves were produced in the Ankole District of south-western Uganda as a part of a beef cattle research program designed to provide information to support a commercial ranching development scheme in an area that had been cleared of the tsetse fly. Breed of sire effects were significant for birth and weaning weight, and breed of dam effects were significant for birth, weaning and 12-mo weight. Breed of sire and breed of dam effects that were significant showed the Boran breed to have higher values for all traits except breed of dam effects on birth weight; calves with Red Poll dams were 3.6 kg heavier (P less than .01) at birth than calves with Boran dams. Steers were significantly heavier than heifers at all ages except birth. Young cows (3 and 4 yr old) and old cows (9 yr old and older) produced calves that weighed significantly less at weaning, 12 mo and 18 mo than calves with dams that were 5 through 8 yr old. Heterosis effects were significant for weights at weaning, 12, 18, 24 and 30 mo of age; generally, heterosis effects on weight increased with age. Heterosis effects approached significance for survival from birth to 30 mo. Additive maternal effects were significant for birth weight; crossbred calves with Boran dams weighted 6.0 kg less at birth than crossbred calves with Red Poll dams. There was a reversal of the reciprocal effect between prenatal and postnatal gains; crossbred calves with Boran dams weighed 7.1 kg more at weaning than crossbred calves with Red Poll dams. Examination of additive direct effects showed the Boran breed to be significantly heavier than the Red Poll breed for birth weight and weaning weight. Additive direct effects showed the Boran breed to have generally higher (P greater than .05) values than the Red Poll breed for most other traits analyzed. Differences between straightbreds of the Boran and Red Poll breeds, which reflect differences in additive maternal and additive direct effects combined, significantly favored the Boran breed for weaning weight and 18-mo weight and favored (P less than .05) the Boran breed for all other traits except birth weight. It was concluded that the Red Poll breed had higher values for additive maternal effects for birth weight than the Boran breed in the climatic and nutritive environment in which this experiment was conducted; for most other traits evaluated, the Boran breed generally had higher values for additive maternal and higher values for additive direct effects than the Red Poll breed.
对1969年出生的202头犊牛、191头断奶犊牛以及182头30月龄犊牛的数据进行了分析，这些犊牛来自博拉恩牛和红白花牛品种及其正反交组合，目的是估计杂种优势、母体加性效应以及从出生到30月龄对存活和生长性状的直接加性效应。这些犊牛产自乌干达西南部的安科莱区，是肉牛研究项目的一部分，该项目旨在提供信息以支持在一个已清除采采蝇的地区开展商业牧场发展计划。父本品种效应在出生重和断奶重方面显著，母本品种效应在出生重、断奶重和12月龄体重方面显著。显著的父本品种和母本品种效应表明，除母本品种对出生重的效应外，博拉恩品种在所有性状上的值都更高；红白花牛母亲的犊牛出生时比博拉恩牛母亲的犊牛重3.6千克（P小于0.01）。除出生时外，所有年龄段的公牛都显著比母牛重。年轻母牛（3岁和4岁）和年老母牛（9岁及以上）所产犊牛在断奶、12月龄和18月龄时的体重显著低于5至8岁母牛所产犊牛。杂种优势效应在断奶、12、18、24和30月龄体重方面显著；一般来说，杂种优势对体重的效应随年龄增加。从出生到30月龄的存活率方面，杂种优势效应接近显著。母体加性效应在出生重方面显著；博拉恩牛母亲的杂交犊牛出生时比红白花牛母亲的杂交犊牛轻6.0千克。产前和产后增重的正反交效应出现了逆转；博拉恩牛母亲的杂交犊牛断奶时比红白花牛母亲的杂交犊牛重7.1千克。对直接加性效应的检验表明，博拉恩品种在出生重和断奶重方面显著重于红白花牛品种。对于大多数其他分析性状，直接加性效应表明博拉恩品种的值普遍高于红白花牛品种（P大于0.05）。博拉恩牛和红白花牛纯种之间的差异反映了母体加性效应和直接加性效应的综合差异，在断奶重和18月龄体重方面显著有利于博拉恩品种，在除出生重外的所有其他性状上有利于（P小于0.05）博拉恩品种。得出的结论是，在本实验进行的气候和营养环境中，红白花牛品种在出生重的母体加性效应方面的值高于博拉恩品种；对于大多数其他评估性状，博拉恩品种在母体加性效应方面的值普遍更高，在直接加性效应方面的值也高于红白花牛品种。
