EFFECT OF NUTRIENT SUPPLY LEVEL ON THE QU ALITY OF MILK ON FARMS

Effect of nutrient supply level on the quality of milk on farms. The e ffects of changes in nutrient supply level on the physico-chemical cha racteristics of milk (especially proteins) and on cheese yield in the dairy industry were measured in 16 herds for 2 consecutive milking bul ks. After the diets were adjusted to INRA's recommended level, an addi tional 2.5 kg concentrate was supplied in a change-over design. This s upply increased true milk protein content by 0.6 g per 1000 and protei n yield by 27 g per cow/d (P<0.01). Casein content increased in the sa me proportions to true protein content The level of nutrient supply di d not significantly influence the proportions of the various caseins a nd whey proteins except for the proportion of alpha S-CN. An additiona l supply of concentrate only increased DM cheese yield (+1.4%).