The objective of this study was to evaluate the apparent digestibility, nitrogen utilization and digestible nutrients by West African Dwarf (WAD)sheep fed mixtures of fermented Oil Palm Slurry (OPS) and Cassava Peel (CaP) based diets. A total of twenty-four (24) female WAD sheep between the ages of 5-6 months, weighing 9.18 – 11.8 kg were allotted to 6 experimental diets in a completely randomized design as follows; one litre of OPS mixed with 1Kg2Kg; 3Kg; 4Kg and 5Kg (Diets A – E) of CaP, respectively while 6Kg (Diet F) of CaP only, served as the control. The experiment lasted fourteen (14) days with feed and water served ad-libitum.Data collected were analyzed to determine apparent nutrient digestibility; nitrogen utilization and total digestible nutrients by WAD sheep. Parameters measured included: Nitrogen intake(N-intake g/d),Feacal Nitrogen g/d (Feacal N), Urinary Nitrogen g/d (Urinary-N), Total Nitrogen excreted g/d (T-N excreted), Nitrogen balance g/d (N-balance) and Nitrogen retention % (N-retention). Digestibility (%) of dry matter, crude protein, crude fiber, ether extract, nitrogen free extracts and total digestible nutrients (TDN) were also determined. Results revealed significant variations (p<0.05) in all parameters measured. Sheep on Diet C (One litre of OPS mixed with 3kg CaP)had the highest values (16.01, 14.0and 75.05%) for N-intake; N-balance and N-retention respectively, while least values (10.00g/d,1.45 g/dand 45.60%) respectively, were obtained for sheep on Diet A (One litre of OPS mixed with 1Kg of CaP). The highest value (5.44 g/d) of T-N excreted was recorded for animals on diets C, while the lowest value (2.05 g/d) was recorded for animals on diet A. Significant reduction in values (1.45g/d and 0.60g/d) were observed for feacal and urinary-N respectively in sheep fed diet C as compared to the increased values of(4.24g/d, 2.50g/d and 1.20g/d, 1.00g/d) for animals placed on diet Aand diet B respectively, (One litre of OPS mixed with 2Kg of CaP). Significant observations were obtained for digestible CP, CF, EE, NFE and TDN, where sheep placed on diet C record highest value of 73.04% and a decreasing value of 58.06% and 53.90% were recorded for animals on diets B and Arespectively. Based on these results. It could be concluded that sheep fed Diet C (1 litre Oil Palm Slurry: 3kg Cassava Peel), gave best results for all the parameters measured compared to other diets fed to sheep.
Key words: Cassava Peel, Digestible nutrients, Nitrogen retention, Oil Palm Slurry, Sheep A