One-day-old piglets were fed diets of either 50% or 14% protein for 8 weeks; they were given intravenous injections with S35-methionine-labeled plasma protein and were given a nonprotein diet. The plasma protein turnover and the nitrogen excreted were estimated by measuring the S35 activity and the nitrogen in aliquots of blood, urine and feces. During a 102-day period of protein privation, the animals that had received the high-protein diet lost little weight, while pigs previously fed a low level of protein lost 4.4 kg. However the high-protein group had a considerably faster rate of plasma protein turnover, catabolized a much large quantity of protein, and excreted more S35 and nitrogen than did the low-protein group. It is concluded that high-protein diets may make pigs less well able to cope with the stress of sudden protein deprivation.
- Copyright © 1962 by the American Academy of Pediatrics