Protein and Energy in the Diet of the Weanling Pig

Abstract
Seventy cross-bred pigs were used to investigate the effect of protein and energy on growth rate from 3 to 7 weeks of age. The 2 × 7 factorial arrangement of dietary treatments included 2 energy levels, (3.0 and 3.5 megacalories (Meal) of metabolizable energy (ME) per kilogram (kg) of diet) and seven protein levels, (12, 14, 16, 18, 20, 22 and 24% crude protein). Nitrogen balance studies were also conducted with four levels of protein (12, 16, 20 and 24%) during a 5-day collection period. There was a positive (P—.01) influence of protein level on weight gain and feed efficiency. A negative (P—.05) linear effect was noted between dietary protein and percentage of ingested and absorbed nitrogen retained. Retained nitrogen expressed on the basis of unit metabolic weight, however, increased with each increase in level of dietary protein. These data suggest that pigs weaned at 3 weeks of age can be fed a diet containing 20 to 24% protein with a calorie: protein ratio of from 15 to 18. Copyright © 1976. American Society of Animal Science . Copyright 1976 by American Society of Animal Science