SEMEN PRODUCTIVITY OF DIFFERENT SWISS GOA T BREEDS

The objective of this study was to evaluate the amount of sperm per br eed in relation to age, season and difference of first and second ejac ulates. A total of 43 bucks were analysed over a 10-year period. There was a highly significant difference in the amount of sperm production between younger and older bucks (0.71 mi vs 0.96 mi), as well as betw een the Saanen on the one hand and the Alpine and Toggenburg on the ot her. It was possible to produce 55% more ejaculates from September to February than from March to August. In all breeds tested, the sperm co ncentration seemed to be higher out of season than during the actual b reeding season. The estimated average-motility of the native sperm was , surprisingly, correlated to the amount of the first and second ejacu lates over a period of months. After repeated semen collection, perfor med at 10-15 min intervals, the volume of the second ejaculates was 15 % lower than of the first ones. Although seasonality is also strongly expressed in the male it may be worth collecting semen all year round.