Hartwig S, Wellmann R, Hamann H, Bennewitz J
Institute of Animal Husbandry and Animal Breeding, University of Hohenheim, Stuttgart, Germany.
J Anim Breed Genet. 2014 Dec;131(6):496-503. doi: 10.1111/jbg.12099. Epub 2014 Jun 26.
During the past decades, migrant contributions have accumulated in many local breeds. Cross-breeding was carried out to mitigate the risk of inbreeding depression and to improve the performance of local breeds. However, breeding activities for local breeds were not as intensive and target oriented as for popular high-yielding breeds. Therefore, even if performance improved, the gap between the performance of local and popular breeds increased for many traits. Furthermore, the genetic originality of local breeds declined due to the increasing contributions of migrant breeds. This study examined the importance of migrant breed influences for the realization of breeding progress of beef traits of German Vorderwald and Hinterwald cattle. The results show that there is a high amount of migrant contributions and their effects on performance are substantial for most traits. The effect of the French cattle breed Montbéliard (p-value 0.014) on daily gain of Vorderwald bulls at test station was positive. The effects of Vorderwald ancestors (p-value for daily gain 0.007 and p-value for net gain 0.004) were positive for both traits under consideration in the population of Hinterwald cattle. Additionally, the effect of remaining breeds (p-value 0.030) on net gain of Hinterwald cattle in the field was also positive. The estimated effect of Fleckvieh ancestors on net gain of Hinterwald cattle was even larger but not significant. Breeding values adjusted for the effects of the migrant breeds showed little genetic trend.
在过去几十年中，外来品种的基因贡献已在许多地方品种中积累。人们进行杂交育种以降低近亲繁殖衰退的风险，并提高地方品种的性能。然而，地方品种的育种活动不像受欢迎的高产品种那样密集且目标明确。因此，即便性能有所提升，但许多性状上地方品种与受欢迎品种的性能差距仍在扩大。此外，由于外来品种的基因贡献不断增加，地方品种的遗传独特性有所下降。本研究考察了外来品种影响对德国前瓦尔德牛和后瓦尔德牛牛肉性状育种进展实现的重要性。结果表明，外来品种的基因贡献量很大，且对大多数性状的性能影响显著。法国品种蒙贝利亚尔牛（p值为0.014）对前瓦尔德公牛在试验站的日增重有正向影响。在前瓦尔德牛群体中，前瓦尔德牛祖先对所考虑的两个性状（日增重p值为0.007，净增重p值为0.004）均有正向影响。此外，其他品种（p值为0.030）对后瓦尔德牛在实地的净增重也有正向影响。弗莱维赫牛祖先对后瓦尔德牛净增重的估计影响更大，但不显著。针对外来品种影响进行调整后的育种值显示出很小的遗传趋势。
