Department of Animal Genetics and Breeding, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana, India.
Zygote. 2022 Aug;30(4):495-500. doi: 10.1017/S096719942100085X. Epub 2022 Jan 12.
The present study evaluated maternal and additive influences that contribute to phenotypic variation in various growth traits in Munjal sheep. The targeted traits that pertained to 2278 records of 706 lambs were birth weight (BWT), weaning weight (WT3), 6-month body weight (WT6), 12-month body weight (WT12), average daily gain (ADG1: 0-3 months; ADG2: 3-6 months, ADG3: 6-12 months of age) and their corresponding Kleiber ratios designated as KR1, KR2 and KR3. The direct heritability estimates for BWT, WT3, WT6, WT12, ADG1, ADG2, ADG3, KR1, KR2 and KR3 under animal models were 0.20 ± 0.08, 0.28 ± 0.08, 0.17 ± 0.07, 0.47 ± 0.09, 0.33 ± 0.08, 0.09 ± 0.06, 0.36 ± 0.10, 0.33 ± 0.08, 0.09 ± 0.06 and 0.32 ± 0.10, respectively. The estimates of maternal genetic effects contributed significantly and were 8% and 7% for BWT and WT3 traits, respectively, which highlighted the considerable role of maternal effects on early growth traits. Genetic and phenotypic correlations ranged from moderate to high between weaning and post-weaning traits. It was concluded that early selection that considered additive as well as maternal effects at weaning age may be delivered to the desired genetic progress in Munjal sheep.
本研究评估了母性和加性因素对 Munjal 绵羊各种生长性状表型变异的影响。目标性状涉及 706 只羔羊的 2278 条记录,包括初生重(BWT)、断奶重(WT3)、6 月龄体重(WT6)、12 月龄体重(WT12)、平均日增重(ADG1:0-3 月龄;ADG2:3-6 月龄;ADG3:6-12 月龄)和相应的克莱伯比 KR1、KR2 和 KR3。在动物模型下,BWT、WT3、WT6、WT12、ADG1、ADG2、ADG3、KR1、KR2 和 KR3 的直接遗传力估计值分别为 0.20 ± 0.08、0.28 ± 0.08、0.17 ± 0.07、0.47 ± 0.09、0.33 ± 0.08、0.09 ± 0.06、0.36 ± 0.10、0.33 ± 0.08、0.09 ± 0.06 和 0.32 ± 0.10。母性遗传效应的估计值显著贡献了 8%和 7%,分别用于 BWT 和 WT3 性状,这突出了母性效应对早期生长性状的重要作用。遗传和表型相关性在断奶和断奶后性状之间从中度到高度不等。结论是,在断奶时考虑加性和母性效应的早期选择,可能会在 Munjal 绵羊中实现所需的遗传进展。