COMPOSITION OF CASSAVA (Manihot spp.) PEELS FERMENTED WITH BOVINE RUMEN LIQUOR AND DIFFERENT NITROGEN SOURCES

This study was carried out to enrich cassava peels in a solid state fermentation with rumen liquor and different nitrogenous sources and to evaluate the nutritive potential of the fermented cassava peels. Fresh cassava peels were washed, sun-dried, grounded and mixed with the various nitrogenous (N) sources (layer-waste, rabbit-waste) at the rates of 0, 50 and 100 g/kg in air tight polythene bags. Contents of each polythene bags were sprayed with 250 ml of rumen filtrate and made airtight for fermentation periods of 0, 72 and 144 hours. The fermented samples were thereafter sun-dried and analyzed. The crude protein value of cassava peels increased with 29.6% and 39.8% as the levels of N-sources increased from 0 g kg-1 to 50 and 100 g kg-1 while 13.5% and 18.7% increment were observed as the fermentation period increased from 0 hour to 72 and 144 hours respectively. The crude fibre (CF) was significantly affected by the level of N-sources (P<.001), fermentation period (P<.001) and their interactions (P<.001) such that the CF value decreased by 22.7% and 37.3% as the level of N-sources increased from 0 g kg-1 to 50 to 100 g kg-1 while it decreased with 10.4% and 11.2% as the fermentation period (FP) increased from 0 hour to 72 hours and 144 hours, respectively. The values of HCN and phytate decreased consistently as the levels of N-sources and FP increased (P<.001). While phy:Zn molar ratio and [Ca][Phy]:[Zn] decreased with increased levels of N-sources and FP, the Ca:Phy molar ratio increased (P<.001) as the levels of N-sources and FP increased. Phy:Zn, Ca:phy and [Ca][Phy]:[Zn] values supports Ca and Zn bioavailability.