Predicting energy × protein interaction on milk yield and milk composition in dairy cows

摘要: Feed management is one of the principal levers by which production and composition milk dairy cows can be modulated in short term. The response yield to variations either energy or protein supplies well known. However, practice, dietary vary simultaneously, their interaction still not understood. objective this trial was determine whether interacted effects on changes diets depended parity potential cows. From results, a model built predict simultaneous relative requirements Nine treatments, defined supplies, were applied 48 divided into 4 homogeneous groups (primiparous multiparous × high low potential) over three 4-wk periods. control treatment calculated cover predicted group middle each cow. other 8 treatments corresponded fixed protein, higher lower than those treatment. results highlighted significant only but also content yield. supply zero with negative balance increased equal requirements. diet greater for potential, primiparous yield, obtained made it possible more accurately cow because composition. In addition, line corresponding limiting 2 factors: protein.