Feed value of enzyme supplemented cassava leaf meal and shrimp meal in pigs
Ten crossbred male pigs of 49.3±3.97 kg body weight were used to evaluate the digestibility, energy value and N (nitrogen) retention of two unconventional protein sources, i.e. cassava leaf meal (CLM) and shrimp meal (SM), with or without the addition of a nonstarch polysaccharide (NSP) enzyme complex (β-glucanase and xylanase). During two trial periods, each lasting 7 days, two pigs each were fed the following five experimental diets: Basal diet (BD), BD+cassava leaf meal with (CLM+E) and without enzyme addition (CLM) and BD+shrimp meal with (SM+E) and without enzyme (SM) supplementation.
Total tract digestibility of Dry matter (DM) was general depressed in pigs fed diets containing the alternate protein sources. Crude protein (CP) and Gross energy (GE) digestibility were depressed in pigs fed cassava leaf meal (CLM) diet. Enzyme supplementation did not improve the digestibility of the energy and other proximate constituents. Faecal N output increased in pigs fed the alternate protein sources while Urine N and N retention were not affected (P>0.05) by the use of the alternate protein sources in the diets of pigs. There was reduced (P<0.05) conversion to ME in pigs fed diets containing the alternate protein sources. The ratio of DE/GE was lower in pigs fed diets containing CLM as compared to the basal diet. The digestibility energy values obtained for CLM, CLM+E, SM and SM+E were 10.2, 8.8, 10.1 and 10.0 MJ/kg DM respectively. Corresponding metabolizable energy were 9.8, 8.3, 9.0 and 9.3 MJ/kg DM, respectively. It was concluded that SM and CLM can be use individually be use in feeding growing pigs as partial substitute for the more expensive conventional plant protein feedstuffs, such as soybean; and can replace up to 23% of the diet of growing pigs.
Keywords: Cassava leaf meal, shrimp meal, digestibility, N-retention, pigs