Relationship between Serum Protein Level and Body Composition in the Chick

Abstract

Studies were conducted with 10-day-old chicks to determine the effect of varying the protein and energy intake on body composition, serum protein levels and the relationship between body composition and serum protein levels. Diets first-limiting in lysine as well as those calculated to be adequate in all the essential amino acids were used. Birds were pair-fed at each protein level to control the energy intake. Fat, moisture, and protein analyses were made on the carcasses of fasted whole birds at the end of a 15-day feeding period. Blood samples were drawn from the chicks not killed for the carcass composition analyses and analyzed for total proteins and albumins. When the dietary protein level was reduced without changing the energy level, both total serum protein and albumin levels were reduced. However, when the daily energy allowance was reduced without changing the protein intake, there was a rise in both total serum protein and albumin levels. There is a very high correlation between either total serum protein or albumin levels and body composition data. The data suggest that serum protein or albumin levels may serve as an index of body composition at a given age.