Biomarkers for negative energy balance and fertility in early lactating dairy cows

Abstract

Most dairy cows suffer from negative energy balance in early lactation that can affect their fertility. Adding fat to the cattle diet increases the diet energy content. In this study, ketone bodies (acetone and acetoacetate), nonesterified fatty acids (NEFAs), and some individual fatty acids in serum and milk were used as biomarkers for negative energy balance and fertility in dairy cows supplemented with two sources of fat. A comparison of calcium salts of palm oil fatty acid versus MixPro-omega-3 (a heat-treated linseed oil) diet on the level of fatty acids in serum and milk of early lactating Holstein cows was assessed in relation to their fertility. The diets were formulated to be iso-nitrogenous and iso-caloric. Two diets were provided from day 0 to 30 days postpartum. Blood and milk samples were collected at 1st, 2nd, and 3rd weeks after calving. Results revealed that the increased serum and milk linoleic and linolenic acid with decreased saturated (palmitic and stearic acid) fatty acids and oleic acid are related to improved energy status with decreasing the ketone bodies and (NEFAs), and enhance the fertility of dairy cows received MixPro-omega-3 when compared with calcium soap fed group. The level of ketone bodies and NEFAs, increased in milk than in serum in the same group. The fertility was enhanced by giving MixPromega-3 diet compared with calcium soap diet.