FEED VALUE OF PROCESSED AND ENZYME SUPPLEMENTED CASSAVA PEEL IN GROWING PIGS

Abstract

Ten crossbred male pigs of 39 ± 3.9 kg body weight were used to evaluate the digestibility, energy value and nitrogen (N) retention of processed and of enzyme supplemented cassava root peel (CRP), as alternatives to increasingly expensive conventional feedstuffs. Employing an incomplete block design, pigs were housed individually in metabolic crates for quantitative collection of faeces and urine. During two 7-day trial periods, two pigs were offered each of the following experimental diets: Basal diet (BD), BD + unprocessed cassava peel without (UCP) and with (UCP+E) enzyme addition, BD + fermented cassava peel (FCP) and BD + retted cassava peel (RCP). Samples of test ingredients, feeds and excrements were analysed for their chemical composition. Fermentation marginally improved the crude protein content of CRP. Retting and enzyme supplementation of CRP improved dry matter, organic matter and gross energy digestibility of the diets. Total N excreted per unit of N intake was higher in pigs fed the UCP diet, resulting in reduced N retention. Digestible and metabolizable energy values (DE, ME) of diets UCP+E, FCP and RCP were not significantly (P>0.05) improved, and energy values (DE, ME) of the four test ingredients ranged from 10.2 to 11.4 and from 9.4 to 11.3 MJ/kg DM, respectively. Results indicated that both retting and enzyme supplementation can improve the use of CRP by growing pigs, whereby retting is cheaper than the use of a multi-enzyme blend in the diet of growing pigs.