The relationship between Holstein bull breeding values for milk yield derived in both the UK and Kenya
The relationship between Holstein bull breeding values for milk yield derived in both the UK and Kenya
复制标题
DOI：
10.1016/s0301-6226(01)00282-2
复制
发表时间：
2002-02-01
期刊：
影响因子：
--
通讯作者：
Pollott, GE
中科院分区：
文献类型：
--
作者：
Ojango, JMK;Pollott, GE
精液的国际贸易导致荷斯坦基因在热带国家广泛用于乳制品生产。热带地区的繁育者可以获得来自出口国的公牛繁育价值，但很少获得来自本国的公牛繁育价值。本研究旨在调查肯尼亚和英国公牛繁殖值对牛奶产量的关系，并通过环境相互作用估计两国之间可能存在的任何基因型对牛奶产量的影响程度。研究人员分析了3185头肯尼亚奶牛和43056头英国奶牛的产奶量数据，其中英国奶牛的数据选自肯尼亚母牛的子代奶牛。两国的产奶量遗传变异存在差异，英国的首次哺乳期305天产奶量遗传力为0.45 +/- 0.02，肯尼亚的遗传力为0.26 +/- 0.06。两国首次泌乳产奶量的遗传相关为0.49 +/- 0.06，表明其基因型受环境互作影响。根据英国育种价值，肯尼亚产奶量的相对响应率估计为英国预期率的44%。尽管使用英国育种价值将导致肯尼亚产奶量的提高，但有些公牛的后代在肯尼亚的产奶量比英国育种价值所暗示的要好。根据目前的研究，在英国得到的育种值（BV）可以用公式-68.8 +/- 0.887（英国BV）转换为肯尼亚的育种值。(C) 2002 Elsevier Science B.V.版权所有
The international trade in semen has resulted in the widespread use of Holstein genes for dairy production in tropical countries. Breeders in the tropics have access to bull breeding values derived in the exporting countries but rarely to those derived in their own country. This study was designed to investigate the relationship between bull breeding values in both Kenya and UK for milk production and to estimate the magnitude of any genotype by environment interaction for milk production that may exist between the two countries. Milk production data from 3185 Kenyan and 43 056 UK lactations were analysed, the UK data being selected from herds containing daughters of bulls also used in Kenya. There was a difference in genetic variance for milk yield between the two countries, with the heritability for first lactation 305-day milk yield being 0.45 +/- 0.02 in UK and 0.26 +/- 0.06 in Kenya. The genetic correlation between first lactation milk yield in the two countries was 0.49 +/- 0.06, implying a genotype by environment interaction in milk yield. The relative rate of response in Kenyan milk yield based on UK breeding values was estimated to be 44% of the rate expected in the UK. Although the use of UK breeding values will lead to an improvement in milk yield in Kenya there are some bulls whose daughters produce better in Kenya than their UK breeding values would imply. From the present study breeding values (BV) derived in the UK could be converted for use in Kenya using the formula -68.8 +/- 0.887(UK BV). (C) 2002 Elsevier Science B.V. All tights reserved.