Flock mating in sheep

摘要

Abstract Semen characteristics before and during the mating period were recorded in three experiments in groups of rams joined with different numbers of ewes. In comparison with pre-joining levels, volume, density, and therefore number of sperm per ejaculate, had fallen to low levels in ejaculates collected 9 days after joining. These low levels were still evident 17 days after joining and were not systematically smaller with higher numbers of ewes per ram, although they varied from 50 to 210. Semen characteristics were similar in two-tooth and six-tooth rams. Ram libido was recorded in 20 min tests before, during and after the mating period in two experiments. The mean number of ejaculates per ram in each test was lower during the mating period than before joining, but was not different in groups joined with different numbers of ewes per ram.