Trail J C, Gregory K E
Trop Anim Health Prod. 1982 Feb;14(1):45-57. doi: 10.1007/BF02281105.
Data were analysed for lactation character of Ayrshire, Ayrshire x Sahiwal, Sahiwal x Ayrshire and Sahiwal females and on survival and growth characters of progeny of Ayrshire, Sahiwal, Simmental and Mixed breed sires mated to these females in the temperate highlands ecological zone of Kenya. The Ayrshire females had significantly higher total lactation yield than the other breeding groups; however, the Ayrshire females received preferential treatment. Despite this the Sahiwal-Ayrshire crosses were superior (3.8%) to the Ayrshire females in productivity index per cow per year because of a shorter calving internal and a higher level of calf survival. Sahiwal females had significantly lower total lactation yield than Ayrshire and Sahiwal x Ayrshire cross females. At 2 years of age female progeny of Sahiwal and Simmental sires were significantly heavier than the female progeny of Ayrshire sires but not of Mixed breed sires, viz. Sahiwal x Ayrshire and calves with sires not known. The Ayrshire breed was shown to be superior to the Sahiwal breed in transmitted effects for milk production and the Sahiwal breed was superior to the Ayrshire breed in transmitted effects for growth rate. It is concluded that the Sahiwal breed has potential to contribute to both milk and beef production programmes when combined in crosses with Bos taurus breeds of cattle in ecological zones similar to the lower to mid-potential areas of the temperate highlands of Kenya.
对肯尼亚温带高地生态区的爱尔夏牛、爱尔夏牛×萨希瓦尔牛、萨希瓦尔牛×爱尔夏牛以及萨希瓦尔牛的泌乳特性进行了分析，并对与这些母牛交配的爱尔夏牛、萨希瓦尔牛、西门塔尔牛和杂交品种公牛后代的存活和生长特性进行了分析。爱尔夏母牛的总泌乳量显著高于其他育种组；然而，爱尔夏母牛受到了优待。尽管如此，由于产犊间隔较短且犊牛存活率较高，萨希瓦尔牛与爱尔夏牛的杂交后代在每头母牛每年的生产力指数方面比爱尔夏母牛高出3.8%。萨希瓦尔母牛的总泌乳量显著低于爱尔夏牛和萨希瓦尔牛×爱尔夏牛杂交母牛。在2岁时，萨希瓦尔牛和西门塔尔牛公牛的雌性后代比爱尔夏牛公牛的雌性后代显著更重，但比杂交品种公牛（即萨希瓦尔牛×爱尔夏牛以及父亲未知的犊牛）的雌性后代重得不显著。结果表明，爱尔夏品种在产奶的遗传效应方面优于萨希瓦尔品种，而萨希瓦尔品种在生长速度的遗传效应方面优于爱尔夏品种。得出的结论是，在与肯尼亚温带高地中低潜力地区类似的生态区，当萨希瓦尔品种与欧洲牛品种杂交时，它有潜力为牛奶和牛肉生产计划做出贡献。
