Replacement of soybean meal by yeast fermented-cassava chip protein (YEFECAP) in concentrate diets fed on rumen fermentation, microbial population and nutrient digestibilities in ruminants

Abstract

Four, rumen-fistulated Holstein-Friesian dairy crossbred steers were randomly assigned according to a 4×4 Latin square design to evaluate replacement of Soybean Meal (SBM) by yeast-fermented cassava chip protein (YEFECAP) in concentrate diets on rumen fermentation, microbial protein synthesis, nitrogen balance and nutrient digestibilities of dairy crossbred steers. Animals were replacement levels of SBM by YEFECAP at 0, 33, 61 and 100%, respectively. The results revealed that daily DM intake, rumen ammonia-nitrogen (9.6, 11.9, 13.8 and 15.1 mg% for treatment 1, 2, 3 and 4, respectively) total volatile fatty acids especially molar of propionate (22.0, 23.1, 26.4 and 27.5% for treatment 1, 2, 3 and 4, respectively), fungal zoospores (3.1, 4.4, 7.4 and 6.8×105cell mL-1 for treatment 1, 2, 3 and 4, respectively) and bacterial population especially cellulolytic bacteria (1.8, 3.0, 4.2 and 5.2×109 cell mL-1 for treatment 1, 2, 3 and 4, respectively) and nutrient digestibities were linearly increased (p<0.01) with increasing percentages of YEFECAP. The apparent efficiency of net microbial protein synthesis in the rumen increased (p<0.01) with concentrate containing proportional increase of YEFECAP. The highest for all parameters were found in treatments 3 and 4 (67 and 100% replacement, respectively). Population of rumen protozoa was significantly decreased with increasing percentage replacement of YEFECAP. Based on this result, the conclusion can be made that using YEFECAP as the main source of protein to completely replace soybean meal was beneficial to cattle in terms of efficiency of rumen fermentation, nutrients digestibities and microbial protein synthesis. However, further study to investigate the use of YEFECAP in productive ruminants especially in lactating cows or feedlot beef cattle should be further investigated. © Medwell Journals, 2010.