Effects of monensin on volatile fatty acid kinetics in steers

Abstract

INTRODUCTION 1 REVIEW OF LITERATURE 2 Introduction to In Vivo Kinetics 2 Microbial Metabolism in the Rumen 9 Measurement of Ruminai VFA Production 12 In vitro technique for rumen VFA production 12 Isotope dilution techniques for rumen VFA production 13 Trans-portal measurement to determine rumen VFA production 24 VFA Metabolism by Ruminant Tissues Measured In Vivo 25 Isotope dilution studies 25 Trans-organ balance studies 29 Mode of Action of Monensin 33 Effects of monensin on animal performance 33 History and chemistry of monensin 34 Effects of monensin on rumen fermentation and microbial population 35 Effects of monensin on rumen turnover and feed intake Effects of monensin on digestibility 43 Effects of monensin on protein metabolism in the rumen Summary of monensin effects MATERIALS AND METHODS Trial 1 Animal management and experimental design Experimental protocol 58 Chemical analyses , Analysis of data Trial 2 70 Animals and experimental design 70 Experimental protocol 71 iii Page Chemical analyses 72 Analysis of data 78 RESULTS AND DISCUSSION Trial 1 Trial 2 84 Combined Results of Trial 1 and Trial 2 96 General Discussion Usefulness of multi-compartmental models Modeling rumen VFA kinetics