A comparative study of non-protein nitrogen supplements for sheep

Abstract

SummaryA basal diet, or the basal diet supplemented with equi-nitrogenous amounts of either ammonium lactate, ammonium acetate or urea was fed to four re-entrant cannulated sheep in a randomized block design.Collections of duodenal digesta were carried out automatically for a continuous period of 4 days following a 10-day equilibration period for each sheep on each diet.Supplementation with non-protein nitrogen increased the passage of total amino acids to the duodenum and increased the proportion attributed to microbial protein. It improved pre-duodenal digestibility of modified acid-detergent fibre and increased post-abomasal digestibility of non-ammonia nitrogen, dry matter and gross energy.Supplementation with non-protein nitrogen increased the energetic efficiency of microbial protein production in the rumen.Ammonium lactate and acetate were safe and effective sources of non-protein nitrogen for dietary supplementation.Supplementation with ammonium lactate led to a greater passage of microbial protein to the duodenum than did equi-nitrogenous supplements of urea or ammonium acetate.