Abstract
A single injection of 1,200 I.U. of PMS prior to the first post-weaning estrus of sows induced superovulation. Litter size was significantly (P<.01) larger in superovulated sows on the 25th and 40th day of gestation. Sows treated with PMS had an average of 2.0 more pigs at farrowing (P<.20). Number of corpora lutea and number of embryos were determined 25 or 40 days after mating in 18 control sows and 19 sows injected with PMS. Conception rate, average number of corpora lutea and average number of living embryos were, respectively, 95%, 13.1 and 10.1 for control sows, and 87%, 25.1 and 15.3 for treated sows. Twelve control sows had an average of 9.3 pigs per litter at farrowing as compared to 11.3 pigs in 20 treated sows. Superovulation was induced in eight sows by repeated treatment with PMS at the subsequent breeding season. Copyright © 1968. American Society of Animal Science . Copyright 1968 by American Society of Animal Science