Effect of Isocarbon-4 and Isocarbon-5 Volatile Fatty Acids on Microbial Protein Synthesis and Dry Matter Digestibility In Vitro

Abstract

We evaluated the effect of a mixture of ammonium salts of isocarbon-4 (31.5%) and isocarbon-5 on microbial nitrogen incorporation and in vitro dry matter digestibility of addition acids (68.5%) on a dry matter basis to batch-culture fermentation systems receiving corn silagebased diets, Isocarbon-4 and isocarbon-5 salts at 1% of dry matter in the diet of 13 to 16% crude protein supplemented with cottonseed or corn gluten meal and urea incubated for 18, 24, or 48 h increased microbial nitrogen incorporation and dry matter digestion at 24-h incubation time. Addition of isocarbon-4 and isocarbon-5 salts at .5, .75, 1.0, and 1.25% of dry matter increased microbial nitrogen incorporation with the corn gluten meal diet and increased dry matter digestion with the corn gluten and cottonseed meal diets, Isocarbon-4 and isocarbon-5 salts at 1% of dry matter in 16% crude protein cottonseed meal, corn gluten meal and urea, soybean meal, or alfalfa haylage and soybean meal diets increased microbial nitrogen incorporation for the alfalfa haylage and corn gluten meal diets. Interaction of crude protein and treatment was not consistent. Addition of isocarbon-4 and isocarbon-5 salts increased dry matter digestion and microbial growth in vitro. © 1985, American Dairy Science Association. All rights reserved.