Effects of dietary supplementation of Mallotus philippensis leaf powder on rumen fermentation pattern, enzyme profile and ciliate protozoal population in growing crossbred calves

Abstract

The aim of this study was to evaluate the effect of dietary supplementation of Mallotus philippensis (local name 'Kamela') leaf meal on rumen ciliate protozoal population, enzyme profile and fermentation characteristics in growing crossbred calves. Ten growing crossbred (Jersey — Tharparker) calves with an average body weight of 91.8±1.37 kg were divided in to two equal groups (G1 and G2) and fed individually under stall feeding for 140 days on a mixed ration containing paddy straw and concentrate mixture in 50:50 ratio. Two types (C1 and C2) of isonitrogenous concentrate mixtures were prepared. Wheat bran in concentrate mixture (C2) of test group (G2) was partially replaced (4 parts w/w) with sun dried ground Mallotus philippensis leaf meal. Experimental calves of test group (G2) were fed Mallotus philippensis leaf meal @ 2% of the diet. No significant differences were noticed between the two groups for daily dry matter intake while nutrient digestibility, i.e. organic matter and cellulose digestibility were higher in Mallotus philippensis leaf fed calves (G2). However, rumen pH, ammonia nitrogen concentration and total rumen protozoal as well as holotrich and spirotrich protozoal population decreased while ruminal TVFA and propionic acid production increased due to supplementation of Mallotus philippensis leaf. Activities of rumen fibre degrading enzymes e.g. carboxymethyl cellulase, xylanase and β-glucosidase enzyme activities were also higher in Mallotus philippensis leaf meal fed calves (G2). It is concluded that supplementation of Mallotus philippensis leaf have a potential for reducing rumen protozoal population and ammonia nitrogen concentration with improving rumen fibre degrading enzyme activities and nutrient digestibility in growing crossbred calves.