LAUSR

Abstract This study was conducted to investigate the effects of North American and Danish feeding strategys on the reproductive performance of American Landrace-Yorkshire (YL) crossbred sows during gestation. A total of 1121 American Landrace-Yorkshire (YL) crossbred sows of parity from 1 to 4 were assigned randomly to “North American System” feeding pattern or “Danish System” feeding pattern during gestation basing on the backfat thickness and body weight. Sows received one diet for gestation and one other for the lactation and were fed ad libitum during lactation. Results showed that over the entire gestation period, there was no difference in average daily feed intake and total feed intake between the two groups (P > 0.05). “Danish system” group significantly improved the backfat thickness at d 30 of gestation (P   0.05). “Danish system” group had significantly improved the total number of born (P = 0.02) and born alive (P = 0.04). The number of total born (P = 0.04), stillborn (P = 0.05) and mummies (P = 0.02), were significantly different in between parities of sows. A significant interaction was observed for mummies (P = 0.01). No difference was observed for the number of weaned pigs, litter weight and piglet weight at weaning, and weaning to oestrus interval between the two groups. However, a significant increase in litter weight and piglet weight at weaning, was associated with parity of sow (P