The Response of Chicks to Dietary Animal Fat in New and Old Environments

NUMEROUS workers have obtained growth responses in chicks from dietary fat additions when nutrient balance was maintained. Rand et al. (1958) observed growth responses to corn oil which could not be attributed to variations in energy intake or intake of other nutrients. They proposed that the observed growth responses were due to one of the following: 1) increasing the efficiency of utilization of metabolizable energy; 2) improving the utilization of dietary protein; and/or 3) providing an unidentified growth factor. In addition to the above explanations for fat responses, there is some evidence in the literature that fat response may be associated with type or quantity of intestinal microorganisms. Supplee (1960) reported a positive growth rate interaction in poults from the addition of corn oil and oleando-mycin to purified diets. The purpose of the experiment reported herein was to measure the growth response to dietary fat under conditions in which …