CLA and its effect on dairy cow fertility with emphasis on low level inflammatory processes

Low fertility and health are a major concern for dairy farms. In the last decades fertility decreased together with the increase of milk yield, but milk yield does not seem the main cause, since not always the most productive cows are the less fertile. Recently a strong negative relationship among inflammation in transition, milk yield and fertility has been observed. Surprisingly, cows with the highest milk yield showed a better energy balance and fertility, but the lower inflammatory status. Despite the results from CLA -based experiments are still “in progress”, CLA supplementation in late pregnancy/early lactation of dairy cows exerts positive effects on reproduction, on inflammatory consequences (lower, likely for the inhibition of NFkB responsible of inflammatory gene expression) and on glucose/energy balance. This suggests to be reasonable a positive relationship between CLA feeding and better fertility through the reduction of inflammation effects and glucose/energy balance improvement.