Free Access
Reprod. Nutr. Dev.
Volume 41, Number 6, November-December 2001
Page(s) 513 - 529
DOI: 10.1051/rnd:2001106

Reprod. Nutr. Dev. 41 (2001) 513-529

Correlation between microbial enzyme activities in the rumen fluid of sheep under different treatments

Ali Moharrerya and Tirta K. Dasb

a  Animal Science Department, Faculty of Agriculture, Shahr-e-Kord University, Shahr-e-Kord, Iran
b  Animal Nutrition Department, Veterinary College, University of Agricultural Sciences, Bangalore 560 024, India

(Received 4 May 2001; accepted 17 December 2001)

Five total mixed rations prepared from finger millet (Eleusine Coracana) straw as a roughage (48%) and mixed concentrate (52%), supplemented with a 1% isoacid mixture (i-C 4, i-C 5, C 5 and phenylacetic acid in equal proportions) or oil (groundnut oil, 5% more than the control) or urea (5% more nitrogen than the control), and protein (groundnut cake, 5% more nitrogen than the control) were given in a Latin square experiment to sheep. Enzymatic activities were estimated for urease, cellulase, protease, amylase, and lipase in various fractions of rumen fluid on the one hand and rumen microbial biomass on the other hand. Rumen samples were taken 3-4 hours after feeding and mixed rumen bacteria were separated as a strained rumen fluid without protozoa (SRFWP), cell free rumen fluid (CFRF) and enzymes associated with the bacteria cell (EABC). Samples of SRFWP and EABC contained higher enzyme activities than CFRF. Depending on the type of enzymes in each fraction, some significant coefficient of determination ( r2) was seen. These values showed very close cooperative action between proteolytic and amylolytic enzymes under the experimental conditions, or perhaps the presence of some species of bacteria with both activities. Lipolytic bacteria are completely specialized for lipase production only ( P < 0.05). The results showed oil, isoacid and crude protein enhanced microbial production ( P < 0.05) and this can change the pattern of enzymes in the rumen of sheep.

Key words: isoacid / urease / cellulase / protease / amylase / lipase / sheep / rumen

Correspondence and reprints: Ali Moharrery

© INRA, EDP Sciences 2001