Dairy ruminants peripartum : effects of energy balance on reproduction and role of lipids on health status and performance

The objective of the experiments described is to study ruminants peripartum with particular regard to the relationship between energy balance and reproduction and dietary fat supplementation and health status. Most critical dairy ruminants period is the last part of gestation and the beginning of lactation. Great evidence that energy balance can affect reproduction in dairy cow has been showed. Results on low milk producing primiparous cows highlighted the important role of IGF-I as sensitive signal between metabolism and reproduction. New nutritional strategies to reduce health problems during peripartum have been proposed. Dietary supplementation with unsaturated fat rich in ω-3 fatty acids has been suggested to act positively on immune response and health status of periparturient goats. Data showed a sort of bearing effect on leukocytes subsets variation diminishing immunosuppressory effect of transition period. Nutrigenomic approach to liver gene expression evaluation in periparturient goats fed diet supplemented with fish oil or palm oil was performed. Data revealed that palm oil supplementation can increase milk production and seems to have greater impact on liver lipid metabolism than fish oil. Hepatic lipid metabolism gene expression in dairy goat seems to respond in different way from dairy cow.