ANTIOXIDANT ADDITIVES EFFECT ON CYTOLOGICAL PARAMETERS OF REFRIGERATED RAM SEMEN

The aim of this study was to assess the influence of antioxidant additives on standard ram semen parameters during storage at 5°C for 0, 24, 48, 72, 96 and 120 h after collection and dilution. Experiments were carried out in extra-season of reproduction (March-June 2009) at Laboratory of Biotechnology for Reproduction from Institute of Research and Development for Sheep and Goats, Palas-Constanta. A total of 36 ejaculates from 2 Merino rams was collected by artificial vagina and were extended with egg yolk-tris buffer, which was containing vitamin E (1mM), cysteine (10mM) and control group without any antioxidant. After diluting sperm is kept in the fridge (5 oC) and for 5 days, at intervals 24 h is checked for qualitative parameters (motility, viability). According to the obtained results for 5 consecutive days, the viability of sperms for control decreased with approximately 70%, while for experimental lots viability was with 59% lower for vitamin E and 60% less when applied cysteine. In the first 72 h the changes in viability of control and the two experimental variants are not important. After 96h, for p<0, 05, viability of control is 39.59±2.78% related to 43.11±2.53%, respectively 43.82±3.56% for extender containing antioxidants vitamin E and cysteine, respectively. Our results show that both vitamin E and cysteine had protective effect over membrane integrity (viability) and motility for the both rams. These finding have practical importance because the seminal material was sampled in extraseason of reproduction when the quality of sperm is lower.