This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by HUNTER, G. L. Articles by LISHMAN, A. W. Search for Related Content PubMed PubMed Citation Articles by HUNTER, G. L. Articles by LISHMAN, A. W.

POST-PARTUM OVULATION AND OESTRUS IN SPRING-LAMBING EWES

Summary.: By means of ovarian examination and teasing with vasectomized rams, the intervals to first post-partum ovulation and oestrus were determined in a 2³-factorial experiment with twenty-four German Merino ewes which lambed between 28th October and 15th November 1966. First ovulation occurred 32·1 ± 1·9 (8 to 45) days after lambing. Three, fifteen and six ewes had none, one or more than three silent ovulations respectively, before showing heat after a mean interval from lambing for all ewes of 57·1±4·5 days. The regression of post-partum interval to ovulation (Y) on ewe's weight 3 days post partum (X) was significant (P<0·01) ; for ewes weighing 83 to 162 lb, Y = 55·15–0·21X. The regression of post-partum interval to oestrus on ewe's weight was not significant, and neither were the effects of treatments, namely, weaning at 3 or 20 days post partum, supplementary feeding of 0 or 1 lb maize grain daily from 3 to 28 days post partum, and joining with vasectomized rams at 3 or 14 days post partum.