Maciel Sónia Maria Ataíde, Fair Michael Denis, Scholtz Michiel Matthys, Neser Frederick Wilhelm Cornelius
Trop Anim Health Prod. 2016 Jan;48(1):75-85. doi: 10.1007/s11250-015-0923-3.
The objective of this experiment was to assess the reproductive and productive performance of Nguni cattle distributed among 11 farms in four regions of South Africa. Only data of registered Appendix A to Stud Proper Nguni animals from the Agricultural Research Council of South Africa’s database were used. Data were collected from 2061 dams and 3285 calves between 1990 and 2009. Overall means for age at first calving (AFC) and calving intervals (CI) were 33.79 ± 4.90 months and 400.29 ± 78.70 days, respectively. Dry season-born heifers had lower AFC than wet season-born heifers. Dry seasons 4 and wet seasons 1 had lower CI than seasons 2 and 3, indicating that conceptions take place between December and May. Average growth weights of calves were 24.87 ± 3.13, 151.91 ± 21.09, 169.25 ± 23.68 and 237.96 ± 27.34 kg at birth (BW), weaning (WW), 12 months (YW) and 18 months of age, respectively. BW was higher in dry seasons 4 and wet seasons 1; WW and YW were higher in dry than in wet seasons. This is the first study demonstrating that performance of Nguni cattle is influenced by ecological regions of the dam’s origin, year-season of birth/calving, breeder’s management, parity and herdbook status, confirming that environment-genotype interactions influence the performance of Nguni cattle in southern Africa. This stimulated a follow-up study on the use of geographic information systems to specifically identify factors influencing the reproductive and productive performance of Nguni cattle in southern Africa.
本实验的目的是评估分布在南非四个地区11个农场的恩古尼牛的繁殖性能和生产性能。仅使用了南非农业研究理事会数据库中注册的符合《种畜良种登记簿》附录A标准的恩古尼牛的数据。在1990年至2009年期间收集了2061头母牛和3285头犊牛的数据。首次产犊年龄（AFC）和产犊间隔（CI）的总体平均值分别为33.79±4.90个月和400.29±78.70天。旱季出生的小母牛的AFC低于雨季出生的小母牛。第4个旱季和第1个雨季的CI低于第2个和第3个季节，这表明受孕发生在12月至5月之间。犊牛在出生（BW）、断奶（WW）、12个月（YW）和18个月龄时的平均生长体重分别为24.87±3.13、151.91±21.09、169.25±23.68和237.96±27.34千克。第4个旱季和第1个雨季的BW较高；WW和YW在旱季高于雨季。这是第一项表明恩古尼牛的性能受母牛出生地的生态区域、出生/产犊的年份季节、饲养者管理、胎次和良种登记簿状态影响的研究，证实了环境-基因型相互作用影响南部非洲恩古尼牛的性能。这激发了一项后续研究，即使用地理信息系统来具体识别影响南部非洲恩古尼牛繁殖性能和生产性能的因素。
