Fermentation Kinetic of Maize Straw-Gliricidia Feed Mixture Supplemented by Fermentable Carbohydrate Measured by In Vitro Gas Production

Abstract

Utilization of crop by-products such as maize straw mixed with legume is expected to be able to overcome the limitation of forage availability during dry season and have similar nutritional value with grass. Addition of fermentable carbohydrate in this diet can be improved fermentability and reduced methane production. The objective of this study was to evaluate supplementation of ground corn grain or rice bran as fermentable carbohydrate in maize straw-gliricidiamixture. Treatment diets evaluated were: Maize straw + gliricidialeaf meal (Control/RO); Control + 10% ground maize grain (ROC); Control + 10% rice bran (RORB). Maize straw was chopped and ground then mixed with gliricidia leaf meal at ratio 60:40% DM. Maize straw-gliricidia mixture then supplemented either with ground corn grain or rice bran at 10% of DM basal diet (control). Sample was incubated for 48 hours, gas production was recorded at 4, 8,12, 16, 24, 36 and 48 hours. Study was conducted in randomized complete design. Results of the study showed that supplementation of fermentable carbohydrate from corn grain or rice bran was able to increased (P<0.05) rate of gas production by 24 and 18% respectively. However only in ROC potential gas production was increased (P<0.05) by 32% and percentage of methane production was decreased. From this study it can be concluded that supplementation of ground corn grain at 10% in maize straw-gliricidia mixture was able to improve diet fermentation and reduced methane production.