Comparison of methods to evaluate the energy supply in dairy herds.

Different methods to evaluate the nutritional and metabolic status in dairy herds are available. The aim of this study was to evaluate three different methods to assess the energy status of the herd: 1) the calculation of the energy balance of the herd with a new method based on the Swiss standard calculations, 2) the "efficiency of the feeding management" based on milk yield and milk protein content (%) obtained from DHI data, and 3) the percentage of cows per herd with an average milk yield (16-25 kg/day), but a low milk protein (< 3.2 %).

Milk yield and composition, nutrition, body conformation traits, body condition scores, fertility and diseases in high-yielding dairy cows--Part 1.

Twenty-nine pairs of high-yielding dairy cows (HC; > or = 45 kg/day reached at least once during lactation) and corresponding control cows (CC; with milk yields representing the average yield of the herds) were examined on 29 Swiss farms from March 1995 to September 1996. The hypotheses were tested that there are differences in feed intake, body-conformation traits, body weight (BW), body condition score (BCS), fertility status and disease incidence between HC and CC cows. Cows were studied 2 weeks before and at 5, 9, 13, 17 and 40 weeks post-partum.