A Model to Describe and Predict the Production and Food Intake of the Dairy Cow

Abstract

A dairy cow gives rise to income from three different sources namely milk, calves, and beef. A model accounting for all three sources is set up. The production of milk and the length of the calving intervals are regarded as stochastic, whereas the beef production represented as the gain in weight is accounted for in a deterministic manner. As regards the milk yield the effects of herd level, the breeding value of the father of the cow, the length of the calving interval, and the milk yield during previous periods are taken into consideration. The parameters of the model are estimated, and the results are discussed. The main purpose of the model is to use it as the biological part of a replacement model.

Key Words:

• Replacement
• stochastic model
• unbiased estimates