Mating Behavior of the Ewe

Abstract

A total of 173 ewes in 24 one-sire breeding pens were observed continuously for one estrous period. Ewes frequently initiated the first sexual contact by seeking out the ram. In general, ewes followed the rams about while in heat. When two or more ewes were in heat simultaneously, certain ewes bunted or crowded other estrous ewes in an attempt to gain the attention of the rams. During an average heat period a ewe was teased 18 times, mounted 25 times and mated 6 times. The average number of hours over which teasing, mounting and mating occurred were 28, 19 and 16, respectively. The number of matings averaged 3.9 for the first half of estrus and 2.4 for the second half. As the number of ewes in heat increased, the numbers of teases, mountings and matings per ewe declined as did interval from first to last mount, interval from first to last mating and matings during first half of heat. Age was positively related to the number of lambs born, but had no significant effect on any of the other variables studied. The more highly inbred ewes had longer estrous periods. The time interval from first tease to first mount was longer for the heavier ewes. None of the mating behavior characteristics were significantly affected by face cover score. Interval from last mount to last tease was the only mating behavior characteristic sig|nificantly correlated with number of lambs born. The time at which ewes exhibited first and last evidence of estrus appeared to be more closely associated with management routine than time of day per se.