Popescu C P
INRA, CRJ, Laboratoire de Cytogénétique, Jouy-en-Josas, France.
Reprod Nutr Dev. 1990;Suppl 1:105s-116s.
Abnormalities in chromosome structure generally have no phenotypic expression but are very often associated with reproductive disorders. In cattle, sheep and goats, the robertsonian translocation seems to be the most frequent abnormality of chromosome structure. In the pig, reciprocal translocations are very common. The accumulation of data on the frequency of such abnormalities and their effects on reproductive performance prompted an evaluation of their economic consequences in cattle and pigs. In cattle, because of the negative effect of 1/29 translocation, an eradication program, based on the removal of carrier bulls from artificial insemination centers was established. In pig, the main effect of the reciprocal translocations was a reduction in the number of offspring, up to 50%, thus representing a considerable economic loss.
染色体结构异常通常没有表型表现,但常常与生殖障碍相关。在牛、绵羊和山羊中,罗伯逊易位似乎是最常见的染色体结构异常。在猪中,相互易位非常普遍。关于此类异常频率及其对繁殖性能影响的数据积累促使人们评估它们在牛和猪身上造成的经济后果。在牛身上,由于1/29易位的负面影响,建立了一项根除计划,即从人工授精中心清除携带易位的公牛。在猪身上,相互易位的主要影响是后代数量减少多达50%,从而造成相当大的经济损失。