Pathological changes associated with dietary protein deficiency in guinea pigs.

Feeding a protein deficient diet containing corn and beans as the protein source for 100 days produced marked malnutrition in guinea pigs. The organs most affected were the liver, pancreas, and testis. Some of the clinical and histological manifestations included growth retardation, atrophy of the liver, decreased number and size of islets of Langerhans, and sterility in male animals. The animals showed clinical signs of protein-calorie malnutrition. This could be the consequence of malabsorption, poor nutrient utilization, and reduced food intake which led to inadequate dietary protein and, secondarily, to inadequate levels of other essential nutrients, especially calories. The low protein level and low biological value of plant proteins used in this study were especially effective in producing the severe pathological changes associated with chronic protein-calorie malnutrition. Some of the changes were marked and incompatible with normal function.