Metabolism, Plasma Amino Acid and Salivary Studies with Steers Fed Corn, Wheat, Barley and Milo All-Concentrate Rations

Abstract

A salivary trial and two metabolism trials with ruminal fluid and plasma amino acid analysis were conducted with steers to compare corn, wheat, barley and milo in all-concentrate rations. Salivary secretion was significantly lower when steers were fed the milo ration compared to when they were fed the corn ration. Total ruminal dry matter was significantly greater when steers were fed either the barley or milo ration than when fed the corn ration. Digestibility of dry matter, crude protein, urinary nitrogen loss and nitrogen retention were all significantly lower when steers were fed the milo ration compared to any of the other rations. Ruminal pH was significantly greater on the milo ration than on the wheat ration. Total concentration of VFA was significantly greater on the wheat and barley rations than on the corn and milo rations. Removal of 1% urea from the corn ration depressed digestibility of dry matter, crude protein and nitrogen retention. The addition of 1% urea to the milo ration increased digestibility of crude protein and urinary nitrogen loss but had little effect on dry matter digestibility and nitrogen retention. Blood plasma urea values differed significantly with treatment and were related to the crude protein content of the ration. Several significant differences were detected in blood plasma amino acid concentrations but these differences could not be related to nitrogen retention or to the dietary amino acid intake. Copyright © 1967. American Society of Animal Science . Copyright 1967 by American Society of Animal Science