Effect of substituting corn with cobs treated with combinations of urea and wood ash on chemical composition and invitro gas production substrate

Abstract

This trial was aimed at determining the effect of substituting corn with cobs treated with urea (25%) and wood ash (75%) on chemical composition and gas production substrate. Corn was substituted with graded levels of treated cobs in the dietary ingredients and the treatments were: 100M = 100% corn, 66M34C = 66% corn with 34% treated cobs, 34M66C = 34% corn with 66% treated cobs and 100C = 100% treated cobs. Samples were analyzed for dry matter (DM), organic matter (OM), ash, crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL); they were then incubated in vitro for 6, 12, 24, 48 and 72 hrs. Results indicated that as corn is substituted with treated cobs, NDF, ADF and ADL also increased, however only the NDS for treatment 100C was reduced. The result of the truly degraded substrate (TDS) parameters also indicated that treatment 34M66C had the highest TDS, gas production (GP), microbial mass production (MMP), efficiency of microbial mass production (EMMP) and partitioning factor (PF). In conclusion, 66% of treated cobs could replace corn in a complete diet without effects on measured parameters