American Journal of Clinical Nutrition, Vol 26, 835-844, Copyright © 1973 by The American Society for Clinical Nutrition, Inc.

Influence of a viral enteric infection on the aminogram and pathology of protein-calorie malnutrition in the pig

¹ From the Departments of Pathology and Animal Husbandry, Michigan State University, East Lansing, Michigan 48823

Three replicated experiments were conducted using 35 young pigs to determine the influence of a viral enteric infection on plasma amino acid values and tissue changes. The pigs were allowed either to nurse the sow or were fed low protein and low or high fat diets.

Decreased and distorted ratios of plasma amino acids were associated with low protein diets, and the enteric infection enhanced the development of a syndrome similar to PCM in man. The manifestations included inappetence, diarrhea, weight loss, emaciation, fatty liver, atrophy of the villi in the jejunum and ileum, skin lesions, and edema. The enteric infection caused lowered and distorted amino acid values in both pigs that were allowed to nurse the sow or those fed low protein diets. Vitamin A reserves in the liver were significantly reduced in infected pigs. In pigs fed low protein diets, there was a decrease in most of the essential amino acids and an increase in nonessential amino acids, especially glycine, alanine, and serine, and thus an increase in the ratio between nonessential and essential amino acids. In the pigs fed the low protein diets, the enteric infection, although it decreased the values for most of the essential amino acids, especially arginine, it had a greater effect on reducing the nonessential amino acids. An increased glycine : valine ratio was a reflection of protein deficiency and an increased alanine:arginine ratio was indicative of enteric infection.