Effect of Masonex (Hemicellulose Extract) on Protein Degradation by Rumen Microorganisms in Vitro and in Vivo

Abstract

Soybean meal was treated with Masonex, a molasses like by-product of the hardboard industry, to determine if some Masonex constituents could react with protein and reduce protein degradation by rumen microbes. In Experiment 1, soybean meal treated with 10% Masonex or cane molasses, with or without extrusion, was incubated in continuous culture fermentors charged with rumen ingesta. The fermentors were fed twice daily for a period of 10 days with a ration consisting of alfalfa meal and treated soybean meal. Total protein output by the fermentors was measured as tungstic acid precipitable nitrogen (TAPN). Following adjustments for small differences in volatile fatty acid production and nitrogen recovery, about 15% more soy protein escaped degradation when treated with Masonex than when treated with cane molasses. This is an approximation based on some assumptions. Masonex from a California source appeared more effective than Masonex from a Mississippi source. In Experiment 2, 48 weanling lambs were divided into two groups with each group fed a ration containing soybean meal which had been extruded with either 10% Masonex or cane molasses at 105 C. There were no differences (P<.05) between the groups regarding growth, feed efficiency, wool growth, and ruminal volatile fatty acids or ammonia concentration. In Experiment 3, six lambs were used in a single reversal design to determine ration digestibility when soybean meal extruded at 104 C with either 10% Masonex or cane molasses was fed. There were no differences (P<.05) in dry matter intake, dry matter and crude protein digestibility, or nitrogen balance. It was concluded that Masonex can react with feed protein and afford some protection against degradation by rumen microbes. Differences exist between source and batch of Masonex, suggesting that the active compounds are either variable in amount or unstable with storage. Copyright © 1978. American Society of Animal Science . Copyright 1978 by American Society of Animal Science.