The effect of the physical form of the diet on the consumption of solid food by calves, and the distribution of food residues in their alimentary tracts

Publisher Website
Google Scholar
Abstract
SUMMARY 1. British Friesian male calves were offered, in two experiments, either chopped, or ground and pelleted dried grass diets to appetite. In one experiment the pelleted diet was also given in restricted quantities. The calves were slaughtered without being fasted, 6 to 9 weeks after weaning, and detailed measurements were made of the weights and volumes of the sections of the alimentary tract and its contents, and of other abdominal organs. 2. Grinding and pelleting the diet reduced mean retention time by approximately 50% and digestibility by 6 to 8 units, and increased dry-matter intake in the two experiments by 55 or 32% respectively, and growth rate by 53 and 69% respectively. 3. The ground and pelleted diets resulted in a smaller quantity of fluid digesta in the rumen, and a much greater quantity in the abomasum and small intestine. 4. There were smaller differences between diets in the quantity of digesta in the combined caecum and colon, or in the total volume of the organs of the abdomen, than in the amount of digesta in the rumen. It is suggested that further critical studies are required upon the importance of the contents of the alimentary tract, or of the abdomen as a whole, in the control of voluntary food intake in ruminants.