The use of diets with different protein sources in lactating goats: Composition of milk and its suitability for cheese production

Four groups, each of 5 Granadina goats in the middle of their second lactat ion, were fed diets which differed in the protein source used to constitute 20% of the total protein content. Diet 1 contained beans, diet 2 sunflower cake, diet 3 corn gluten feed and diet 4 cottonseed. Milk yield and the ch emical composition of the milk was determined as was the suitability of the milk for coagulation and the yield of cheese. The daily milk yield did not vary significantly in relation to diet. The milk obtained from animals con suming diet 3 showed the highest protein (35.4 g/l), casein (28.4 g/l) and beta-casein (18.8 g/l) contents and the highest cheese yield (26.2%). The l owest values were obtained from animals on diet 2 (28.5, 18.7, 9.5 g/l and 20.1%, respectively). From multivariate analysis it was possible to deduce that the amount of coagulable protein, especially beta and kappa-casein and fat content were the DM components of the milk most directly related to ch eese yield. It was also possible to establish a hierarchy among the four pr otein sources. (C) 1998 Elsevier Science B.V. All rights reserved.