Reciprocal translocation in four boars producing decreased litter size

摘要

Four boars with a normal semen picture, normal sexual behaviour and normal incidences of repeat breeding and malformations but giving rise to considerably decreased litter size were found to be translocation carriers. Two of them had a translocation involving chromosome 1. rcp(Ip+14q –) and rcp(lq-;17q +), respectively; both were presumptive new mutations. The other 2 boars, littermates, had the same reciprocal translocation. rcp(5q -;8q +), which was presumably inherited from their dam. All three translocations concerned unequal-sized chromosome segments and five of the breakages preceding the translocations occurred in RHA positive bands close to the centromeres and telomeres. Mitotic and meiotic chromosome morphology was investigated.