Processing Strategies Modifies Nutrient Composition of Cassava Peel-leaf Blends, Influences Nutrient Digestibility and Nitrogen Balance of Growing Pigs

Abstract

This study investigated the effect of processing strategies on nutrient composition of cassava peel-leaf blends (CPLB) and impact on apparent nutrient digestibility and nitrogen balance of growing pigs. In-vitro fermentation of CPLB (Cassava peel: Cassava leaf; 5:1) using five spore forming organism was first carried out to evaluate the fermentative efficacy of the microbes. Aspergillus tamarii which had increased (P < 0.05) crude protein (10.70%) and reduced (P < 0.05) acid detergent fibre (ADF) (28.70%) was selected for solid state fermentation (SSF) of CPLB. The diets formulated for digestibility consists of standard corn-soya based diet (Control) and three other diets were formulated by replacing maize with unfermented CPLB (UCPLB), water fermented CPLB (WCPLB) and microbial fermented CPLB (MCPLB) using Aspergillus tamarii as inoculum. 24 cross bred male pigs of average weight 65.96 kg ± 1.56 were used for the trial. Nutrient composition of test ingredients shows that MCPLB had the highest (11.68%) crude protein. Digestibility of diets shows that crude fibre and NDF digestibility was higher (P < 0.05) in pigs fed diet containing UCPLB and WCPLB. In conclusion, fermentation of CPLB improved protein content of the fibrous feed stuff and dietary inclusion of processed CPLB did not cause significant reduction in nitrogen retention in pigs.