Abstract The ability to identify ewes that can outperform their contemporaries, in terms of how long they remain productive in the flock, will help towards improving flock efficiency and profitability. The main objectives of this study were to: (1) identify the main reasons for mortality or culling within diverse sheep production systems in Ireland, Norway and UK; (2) investigate the influence of early life factors on ewe longevity within each of these systems; and (3) determine whether common approaches or recommendations could be employed to improve ewe longevity. The main reasons for mortality or culling were, in addition to old age, mastitis (Irish and Norwegian sheep) and tooth loss (UK hill sheep). In each country, there were significant differences in age at last lambing due to the year the ewe was born (but in no consistent pattern), and due to her flock of birth (P

中文翻译：

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欧洲三个国家养羊场母羊寿命的影响因素

摘要 根据母羊在羊群中保持生产力的时间长短，识别性能优于同时代母羊的能力将有助于提高羊群效率和盈利能力。本研究的主要目标是：(1) 确定爱尔兰、挪威和英国不同绵羊生产系统中死亡或宰杀的主要原因；(2) 在每个系统中研究早期生命因素对母羊寿命的影响；(3) 确定是否可以采用常见的方法或建议来提高母羊的寿命。除了年老之外，死亡或扑杀的主要原因还有乳腺炎（爱尔兰和挪威羊）和牙齿脱落（英国山羊）。在每个国家，由于母羊出生的年份不同，最后产羔的年龄存在显着差异（但没有一致的模式），