A Re-Assessment of the Mode of Action of the Growth-Stimulating Properties of Antibiotics

Abstract

FOLLOWING discovery of the growth-stimulating properties of dietarily administered antibiotics for the chick, it was reported that the growth response may be due, in some instances, to a sparing effect on the dietary requirement for vitamins of the B-complex (Biely and March, 1951). There are numerous reports in this regard pertaining to other animals as well as the chick. Combs (1955) has tabulated the results obtained with chicks published by different investigators. Although the concept that antibiotics may have a sparing effect on dietary vitamin requirement has been generally upheld, the findings are not consistent as to which vitamins are spared and which are not.The following experiments were conducted in an attempt to determine the reason or reasons for the discrepancies in the response to antibiotics of chicks fed diets deficient in different vitamins of the B-complex. The experiments were carried out over a period of four years to …