PSIX-8 Evaluation of Siam weed (Chromolaena odorata) leaves as a modifier of rumen fermentation in West African dwarf bucks

Abstract

Abstract Recently, bioactive component of plant and plant parts have been used as rumen modifier to reduce methane gas production in ruminant livestock so as to reduce their contribution to the implicated greenhouse effect. This study therefore, evaluated the potential of Siam weed (Chromolaena odorata) leaves as a modifier of rumen fermentation in West African dwarf bucks. Fresh C. odorata leaves were harvested, air dried (3 weeks), milled using a 2mm sieve size and bagged for both proximate and phytochemical analysis. Concentrate diets were formulated with C. odorata leaf meal included in the diet at 0, 2, 4 and 6% of the whole diet. Rumen fluids were collected from West African dwarf (WAD) bucks (averaged 25kg) using suction tube and randomly allotted to the 4 experimental diets in a Completely Randomized Design. Incubation of inoculums was done for 96hrs with 12 replicates per treatment in a single run. Data obtained were analyzed using a One-way Analysis of Variance and means compared using Tukey’s Test. Results indicated that C. odorata had 969.0mg/kg dry matter, 175.1mg/kg crude protein, 204.3mg/kg crude fibre, 521.6mg/kg nitrogen free extract, 19.9 mg/kg saponin, 25.7 mg/kg tannin, 10.8mg/kg flavonoid and 12.6 mg/kg alkaloid. The addition of 2 and 4% C. odorata to the diets resulted in increased (P < 0.05) in vitro gas production while C. odorata at 2 % reduced (P < 0.05) the methane gas (%) estimate. In vitro organic and dry matter digestibilities, total digestible substrates and short chain fatty acids were increased (P < 0.05) with C. odorata addition to the diets. This study concluded that the use of C. odorata as an additive at 2 and 4% inclusion increased total gas output; however, 2% inclusion will be beneficial as it reduced the methane output while maintaining higher gas production and digestibility.