Abstract
The effects of full and limited-feeding on reproductive phenomena were studied in Poland China, Yorkshire and their reciprocal cross-bred gilts. Full-feeding was applied from either day-10 to day-15 or from day-15 to estrus. Gilts of the former group were slaughtered either on day-15 or on day of estrus. Full-feeding from day-10 to day-15 increased the weight of follicular fluid and decreased the ratio of the number of small follicles to the number of medium follicles at day-15. However, these effects were lost by estrus after reducing the feeding level from day-15 to estrus. Full-feeding for the last 4 to 6 days of the estrous cycle increased the weight of follicular fluid and the number of large follicles and lessened the ratio of the number of small to the mean number of medium and large follicles. Evidence of heterosis was shown in the weight of follicular fluid at day-15, the crossbred value exceeding that of the greater parent. Although the pure-breds were not found to differ at day-15, differences were shown at estrus in several follicular components. Copyright © 1972. American Society of Animal Science. Copyright 1972 by American Society of Animal Science.