Nutritional restriction in lactating primiparous sows selectively affects female embryo survival and overall litter development

Autor: Walter T. Dixon, S. Novak, Michael K. Dyck, M. D. Vinsky, George R. Foxcroft
Rok vydání: 2006
Předmět:
Zdroj: Reproduction, Fertility and Development. 18:347
ISSN: 1031-3613
DOI: 10.1071/rd05142
Popis: This study explored the possibility of sex-specific effects on embryonic survival in primiparous sows subjected to restricted feed intake during the last week of lactation and bred after weaning (Restrict; n = 16), compared with control sows fed close to ad libitum feed intakes (Control; n = 17). Restrict sows were in a substantial negative net energy balance at weaning, and lost 13% of estimated protein and 17% of fat mass during lactation, yet the weaning-to-oestrous interval and ovulation rate were not different between treatments. However, embryonic survival at Day 30 of gestation was lower (P < 0.05) in Restrict than Control sows, and selectively reduced the proportion of female embryos surviving (P < 0.01). A decrease in weight and crown–rump length of surviving female (P < 0.05) and male (P < 0.05) embryos was seen in Restrict litters. The mechanisms mediating this sex-specific effect on embryonic loss in feed-restricted sows are unclear. The data presented here indicate that feed-restriction during the last week of lactation in primiparous sows causes a selective decrease in survival of female embryos and limits the growth of all surviving embryos.
Databáze: OpenAIRE