EN
The aim of this study was to analyze the reasons for abnormal meiosis in an infertile boar, the carrier of a reciprocal translocation, rcp(9;14)(q14;q23). The study was based on observations of synaptonemal complexes, the protein structures occurring during pairing of chromosomes. The specific morphology of the X-Y bivalent at different stages of pairing made it possible to identify several substages of prophase I: late zygotene (Z/P), early pachytene (P1), mid pachytene (P2) and late pachytene. A total of 448 primary spermatocytes were evaluated. In all cells the authors observed the presence of a structure characteristic of reciprocal translocations . a tetravalent formed from chromosomes created as a result of an exchange of chromatids between autosome pairs 9 and 14 and their homologues.