Negussie F, Kassa T, Tibbo M
Addis Ababa University, Faculty of Veterinary Medicine, PO Box 34, Debre Zeit, Ethiopia.
Trop Anim Health Prod. 2002 Jul;34(4):319-28. doi: 10.1023/a:1015634802832.
An investigation was carried out into the behavioural and physical signs of oestrus in 70 Fogera cows and heifers between December 1993 and May 1994 at Metekel Cattle Breeding and Improvement Ranch, Ethiopia. Retrospective information generated from records made between 1991 and 1994 was evaluated for some aspects of the reproductive indices. The mean +/- SD duration of oestrus (n = 136) was 10.6 +/- 4.5 h (range 2.2-21). Most oestruses (63.2%) started during the day (06:00-18:00). The incidence of oestrus was significantly affected by months (chi 2 = 21.86; p < 0.001). Among the physical signs, standing to be mounted was the most consistent indication (97.8%) of oestrus. About 12.5% of the cows in oestrus did not mount other cows. The retrospective study indicated that the mean interoestrus interval for 46 oestruses was 29.2 +/- 19.7 days. The average gestation length for 141 cows was 276 days. Continuous and careful observation of oestrus would reduce the reproductive wastage that arises from less pronounced heat periods and those occurring at night, especially for ranches that use artificial insemination and have a limited number of bulls.
1993年12月至1994年5月期间，在埃塞俄比亚的梅泰凯尔牛育种与改良牧场，对70头福格拉母牛和小母牛发情期的行为和身体体征进行了调查。对1991年至1994年期间记录产生的回顾性信息进行了生殖指标某些方面的评估。发情期的平均持续时间（±标准差，n = 136）为10.6 ± 4.5小时（范围为2.2 - 21小时）。大多数发情期（63.2%）在白天（06:00 - 18:00）开始。发情发生率受月份的显著影响（χ² = 21.86；p < 0.001）。在身体体征中，站立接受爬跨是发情最一致的表现（97.8%）。约12.5%处于发情期的母牛不爬跨其他母牛。回顾性研究表明，46次发情的平均发情间期为29.2 ± 19.7天。141头母牛的平均妊娠期为276天。持续且仔细地观察发情期将减少因发情期不明显以及在夜间发情而导致的生殖浪费，特别是对于采用人工授精且公牛数量有限的牧场。
