Assessment of energy balance in dairy cattle

Abstract

Between April 2006 and March 2015, a recent survey in UK commercial dairy herds has shown that approximately half of cows in the last 10 days before calving and three quarters of cows in the first 20 days in milk had evidence of excessive negative energy balance (eNEB). However, herd variation is significant, and many herds manage to keep cows with impressive milk yields in satisfactory energy balance around calving. Whatever method of assessment is used for eNEB, it needs to take into account selection of cows for sampling, stage of the production cycle to target ‘at risk’ periods (within 10 days of predicted calving date in dry cows, and the first 3 weeks of lactation in freshly calved milking cows), group size and use of background information. Interpretation of the results is key, and this requires a holistic view of both the ration and nutritional management.