EN
The studies were carried out on 25 highly pregnant young sows and 25 highly pregnant multiparous females. Two groups were formed: group I (experimental) comprised 15 young and 15 old sows which were being given 300 mg daily beta-carotin contained in the drug Rovimix from the day 100 of pregnancy for 35 days of lactation to the next fertilization: group II (control) contained 10 young and 10 old sows. The addition of beta-carotin caused a significant incerease of vitamin A in the colostrum of the experimental sows and improved to some extent all parameters of reproductive usefulness. There was found an increased number of alive born piglets, a decreased percentage of losses in the period of sucking and a shorten period from weaning to the effective covering of sows.