Prospective study of the effects of the 1/29 Robertsonian translocation upon the fertility of Marchigiana males

Abstract

The effects of the 1/29 transIocation on fertility of Marchigiana males were investigated on a prospective study. We have compared normal Nelore females artificially inseminated by an heterozygote Marchigiana sire (experimental group) with those resulting from a normal male insemination (control group). We could observe: 1. Higher mean number of A.I. I conception in the experimental group; 2. Significant reduction of pregnant females at first service, in the experimental group; 3. No difference in the period between the A.I.(s) or in obortion rates, in both groups; 4. F1 obtained from experimental group were analysed and the 1/29 distribution does nor differ from 1:1. The reduction of fertility may be due to zygotic loss and/or production of aneuploidy gametes. We have performed a meiotic and spermatic study in two heterozygote 1/29 translocated males resulting from Marchigiana x Nelore crossbreed. We found alterations in the spermatic characteristics of the heterozygote, mainly reduction of sperm concentration/mm³. Meiotic analysis of a translocated male shows no association between any autosome and the sex vesicle