RESULTS CONCERNING THE FREEZING PRETABILITY OF BUCK SEMEN AND FECUNDITY AFTER ARTIFICIAL INSEMINATION OF LOCAL GOAT
Stela Zamfirescu, Dorina Nadolu
The aim of this study was to evaluate the freezing pretability of semen collected from 38 bucks Alpine and Saanen breeds, imported from Germany(2005). For this reason semen was frozen in Tris and Natrium citrate extenders, besides seminal plasma, using the rapid freezing methodin liquid nitrogen. The results of freezing pretability of semen were valuated by monitoring spermatic and cryobiological index : the fresh semen motility versus freezing-thawing semen motility at 24 h after freezing, motility after Bloom staining of spermatozoa, ultrastructural damages studied by electron microscopy and finally, by direct testing of fecundante capacityof spermatozoa by artificial insemination of goat. The mean values of fresh semen motility were 86.81±0.88% for Alpine and 85±2,24% for Saanen, while after defreezing were 46.34±2.66% for Alpine semen and 56.12±4,02% for Saanen semen. Some ultrastructural damages were observed in freezing-thawing spermatozoa (partial and integral plasmatic membranae loss, nuclear and mithocondrial degenaration). The results were appreciated by „in vivo” testing of frozen semen, using artificial insemination of goats and monitoring the fecundity and prolificacy. So, we obtained a very good fecundity (60%) after artificial insemination of very good motylity of the spermatozoa. All the results showed that buck semen has high pretability to freezing and can be used for artificial insemination. This study followed to find a possibility to preserve the good quality semen and to be distributed in time and space for the amelioration of the Romanian local goats.
Key words: frozen semen, pretability, motility, fecundity, prolificacy