The feed intake in dairy cows and its prediction during lactation

Abstract

The accuracy of intake prediction is essential to formulate diets, because intake is the major cause of variation of nutrient supply. Thisarticle was aimed at explaining the recent evolution of the INRA system (Fill Unit System) of voluntary dry matter intake prediction indairy cows. The first part analyses the complex relationship between milk yield and intake, which led to the introduction of the notion ofpotential milk yield in the equation predicting intake capacity. The second part considers the relationships between intake and regulationof body reserves and shows the importance of considering the role played by these body reserves in the prediction of intake in early lactation.The last two parts detail the new equations of intake capacity of dairy cows and of concentrate fill values in early lactation : theseequations improve the intake estimation with a more dynamic and accurate prediction during lactation.