THE EFFECT OF EQUILIBRATION TIME ON THE QUALITY OF FROZEN SEMEN OF ETTAWA CROSSBRED AND BOER GOAT

Abstract

One of the most important factors in processing of frozen semen is the time given
for the sperms to adapt with cold temperature (equilibration time) before fieezing take place. In the present study, semen of five heads of bucks fiom each bmd, Emwa
Crossbred (PE) and Boer goats, was collected weekly. Good quality semen was diluted in Tris diluent at room temperature, and put into a minisnaw. Thereafter, temperature was decreased slowly to 4-5°C within 60 minutes and it was maintained in this level for 1, 2 and 3 hours before freezing. The best-frozen semen obtained was used for artificial insemination Results of the study showed that ejaculate volume of PE and Boer goats varied 0.3 - 1.5 cc/ejaculate, with motility score of 65-75% and live sperms of >70%. The second ejaculate showed better quality than those of the first ejaculate. The quality of frozen semen shown by motility (25-45%) and live sperms (35-65%) varied widely. Equilibration time (l-3 hours) significantly affected the quality of fi‘0Zer1 semen, in which 3-hours equilibration time gave the best results. In-vivo fertility test of frozen semen of PE and Boer goats showed pregnancy rates of 31.43% and 31.25%, respectively. It can be concluded that 3-hours equilibration could give a better frozen semen quality compared with l and 2 hours, though in-viva test showed a relatively low pregnancy rate.