Identification of heterosomes in spermatoza of rams with 54,XX/54,XY chimerism
The aim of the study was to identify heterosomes in the semen of three Romanov rams – carriers of leukocyte chimerism (FISH technique) and to determine the proportions between spermatozoa with X and Y chromosomes. The choice of bovine probes for hybridization with ram heterosomes was dictated by genetic conservatism of bovine and ovine heterosomes. The ratio between spermatozoa with a yellow fluorescent signal containing the X chromosome in the haploid set and spermatozoa with a red-purple signal indicating the presence of the Y chromosome, taking into account spermatozoa with no signal, was 52%:43%:5% in ram No. PL100006077676; 47%:44%:9% in ram No. PL100006078031; and 48%:46%:6% in ram No. PL100006078895. The results obtained lead us to conclude that the 54,XX/54,XY chimerism has no effect on sex ratio in offspring.