Cunningham Kirsty, Van Burgel Andrew, Kelman Khama R, Macleay Claire M, Paganoni Beth L, Thompson Andrew N
Department of Primary Industries and Regional Development, 453 Katanning-Nyabing Rd, Katanning, WA 6317, Australia.
Department of Primary Industries and Regional Development, 444 Albany Highway, Albany, WA 6330, Australia.
Animals (Basel). 2022 Jul 1;12(13):1707. doi: 10.3390/ani12131707.
Ewes often lamb over extended periods so the level of nutrition during pregnancy and lambing may be suboptimal for ewes that conceived later during mating. Predicting lambing dates would allow cohorts of ewes with similar gestational ages to be managed more precisely to achieve targets for ewe nutrition, feed on offer, mob sizes and access to shelter to improve lamb survival. The interactions between ewes and rams during mating have been used to predict the time of oestrus and lambing dates successfully, but this has not been tested at a commercial scale. In this study, proximity sensors were used to measure interactions between inexperienced Merino ewes ( = 317) and experienced rams ( = 9) during a 27-day mating period under commercial production conditions. When the gestation length was assumed to be 150 days, 91% of lambing dates were predicted within ±6 days of the actual birth date of lambs and 84% of lambing dates were predicted within ±3 days. The use of proximity sensors during mating was an effective means of predicting lambing dates, and there was no significant difference in accuracy for single bearing verses multiple bearing ewes. However, DNA parentage data showed the ram corresponding with the maximum daily interactions ratio was the sire for only 16% of all progeny, suggesting they could not be used to indicate the sire of the progeny.
母羊的产羔期通常较长，因此对于在配种后期受孕的母羊来说，怀孕和产羔期间的营养水平可能并不理想。预测产羔日期可以更精确地管理妊娠期相似的母羊群，以实现母羊营养、饲料供应、群体规模和遮护条件等方面的目标，从而提高羔羊的存活率。交配期间母羊与公羊之间的互动已被成功用于预测发情时间和产羔日期，但尚未在商业规模上进行测试。在本研究中，在商业生产条件下，使用接近传感器在27天的交配期内测量了317只未经验的美利奴母羊与9只经验丰富的公羊之间的互动。当假定妊娠期为150天时，91%的产羔日期预测在羔羊实际出生日期的±6天内，84%的产羔日期预测在±3天内。交配期间使用接近传感器是预测产羔日期的有效方法，单胎母羊和多胎母羊在预测准确性上没有显著差异。然而，DNA亲子鉴定数据显示，与每日最大互动比例相对应的公羊仅为所有后代的16%的父亲，这表明它们不能用于确定后代的父亲。
