Modeling milk production and labor efficiency in modernized Wisconsin dairy herds.

The 1999 Wisconsin Dairy Modernization Project was conducted to examine variation in milk production and labor efficiency among herds that had recently expanded. Data were obtained from a sample of Wisconsin herds that expanded between 1994 and 1998. Using rolling herd average milk production in 1998 as the dependent variable in the milk production model, milking frequency, bovine somatotropin use, sprinkler use, average linear somatic cell score, average age at first calving, average days dry, and rolling herd average milk production in 1994 predicted 69% of the variation in milk production. Milking three times daily, using bovine somatotropin, using sprinklers to cool cows, and decreasing linear somatic cell score, age at first calving, and days dry were associated with increased milk production. Each of these variables supports previous research from designed experiments with on-farm results. Variation in milk production is determined primarily by differences in management ability and management practices employed by the dairy producer. Using cows per full-time equivalent as the dependent variable in the labor efficiency model, acres per cow, number of people involved in the milking operation, milking system type, herd size, and interactions between milking system types and herd size predicted approximately 43% of the variation in labor efficiency. As expected, labor efficiency increased with larger herd sizes, fewer acres per cow, and fewer people involved in the milking process. Parallel milking parlors were associated with the highest cows per full-time equivalent followed by herringbone parlors, flat barns, and stall barns.