Abstract:
Introduction: Chinese Holstein in South China suffer heat stress for a long period, which leads to evolutionary differences from Chinese Holstein in North China. The aim of this study was to estimate the genetic parameters of fertility traits for Chinese Holstein in South China. Methods: A total of 167,840 Chinese Holstein heifers and cows from Guangming Animal Husbandry Co., LTD farms were used in this study. The fertility traits analyzed were calving interval (CI), days open (DO), age of first service (AFS), age of first calving (AFC), calving to first insemination (CTFS), first insemination to conception (FSTC), gestation length (GL), non-return rate to 56 days (NRR), and number of services (NS). Results: The descriptive statistics revealed that the same trait in heifers performed better than in cows, which was consistent with the other studies. The heritabilities of fertility traits in this study ranged from close to 0 (for NS of cows) to 0.2474 (for AFC of heifers). The genetic correlation of NRR between heifers and cows was 0.9993, which indicates that the NRR for heifers and cows could be treated as one trait in this population. Conclusion: The heritabilities of fertility traits in Chinese Holstein in south China were quite different from the heritabilities of fertility traits in North China. NRR56, NS, AFC, and CI were suggested to be included into the selection index to improve fertility performance of Chinsese Holstein of south China. The results of this study could provide genetic parameters for the animal breeding program of Chinese Holstein in the south of China.
摘要:
简介:中国南方的荷斯坦人长期遭受热应激,这导致了与中国北方荷斯坦的进化差异。本研究的目的是估计中国南方荷斯坦地区生育力性状的遗传参数。方法:从光明畜牧业有限公司收集167,840头中国荷斯坦母牛和奶牛。本研究使用了LTD农场。分析的育性性状为产卵间隔(CI),开放天数(DO),首次服役年龄(AFS),第一次产牛年龄(AFC),产卵至第一次授精(CTFS),第一次授精到受孕(FSTC),妊娠长度(GL),无回报率至56天(NRR),和服务数量(NS)。结果:描述性统计显示,相同性状的小母牛表现优于奶牛,这与其他研究是一致的。在这项研究中,生育力性状的遗传力范围从接近0(对于奶牛的NS)到0.2474(对于小母牛的AFC)。母牛和母牛之间NRR的遗传相关性为0.9993,这表明母牛和母牛的NRR可以作为该群体的一个性状。结论:中国南方荷斯坦地区生育力性状的遗传力与北方地区生育力性状的遗传力差异较大。NRR56,NS,AFC,建议将和CI纳入选择指数,以提高中国南方荷斯坦的生育绩效。本研究结果可为中国南方荷斯坦地区的动物育种提供遗传参数。