Pruteen, a new source of protein for growing pigs. I. Metabolic experiment: Utilization of nitrogen

Abstract

Pruteen, a bacterial protein (Imperial Chemical Industries, Ltd., Billingham, Cleveland, Great Britain), contained 740 g crude protein (nitrogen × 6.25)/kg, of which 147 g/kg was nucleic acid, and its amino acid composition was similar to that of white fish meal. The value of Pruteen as a protein supplement to diets based on barley and fine wheat offal was compared with that of white fish meal in a metabolic trial covering the live weight range from 20 to 60 kg. The two supplements were compared at a “standard” level, commonly used in practice, and a “marginal” level, discounting the nucleic acid of Pruteen. There was no significant difference in growth rate, feed: gain ratio, N retention, or apparent digestibility of N, energy or most of the amino acids between the diets supplemented with Pruteen and those supplemented with fish meal. The pig can dispose of nucleic acid at the levels of intake tested.