Reaction of some rumen micro flora to different supplementary feeds in rumen fistulated animals

Abstract

Ruminant animals lack enzymes to break down fibrous feeds but they harbor microorganisms capable of degrading their feeds. Rumen microbes are affected by feed substrates. The purpose of this study was to evaluate rumen microbial changes as the function of varying supplementary feeds. Two protein supplements (cottonseed cake and tree lucerne) and two energy supplements (wheat bran and molasses) were offered to rumen fistulated oxen of two groups varying in age. The supplements vary mainly in protein and fibre contents. Switch over design was used in the experiment and the oxen were switched to another supplement after one week to avoid the carryover effect. Microbial populations, correlations with feed nutrient composition and enzyme assays in each case were studied and JMP 5.1 computer software was used for the analysis. Both the bacterial and fungal populations were the highest in oxen supplemented with cottonseed cake (10.7x1011cfu/ml bacteria & 10.8x105cfu/ml fungi) in both young and older oxen (7.4x1010cfu/ml bacteria & 7x105cfu/ml fungi), respectively. The total microbial populations were higher in younger groups supplemented with similar supplement than the older groups of oxen and the least microbial count was observed in those supplemented with tree lucerne (Chamaecytisus palmensis). The enzyme activities were also compared and showed significant variations and linear relation with the nutrient compositions of the feeds. A supplement rich in both fibre and protein supported dynamic rumen microbial population and is very important for the production of quality animal products.