ABSTRACT
Fat makes a significant contribution to the energy value of the diet of a calf drinking milk but it normally plays little part in the nutrition of the post-weaning calf since it cannot be broken down in the anaerobic environment of the rumen. The increasing intake of solid food, and particularly the end products of rumen fermentation, which are principally the steam-volatile fatty acids, acetic acid, propionic acid and butyric acid, stimulate rapid rumen development. Dietary protein is broken down by digestion into its individual components, the amino acids. If a protein is fed in excess of requirement for the specific purpose of promoting body protein deposition, the amino acids will be used as sources of energy and lost. Colostrum or 'beestings' is essentially milk reinforced with plasma proteins and vitamins, which concentrate in the udder in the last few days before calving.
