ABSTRACT

Six experiments were conducted to evaluate the nutritional and feeding value of fungi (Pleurotus tuber regium) degraded (PTRMC) and non-biodegraded (NBMC) maize cobs in West African dwarf (WAD) goats. The nutritional and anti-nutritional properties of untreated maize cobs and biodegraded maize cobs were evaluated in experiment 1. The results showed that biodegraded maize cobs had significantly (P<0.05) higher concentrations of crude protein, ash, nitrogen-free extract, calcium, phosphorus, potassium, magnesium, and iron compared to the untreated maize cobs, while the NBMC had significantly higher (P < 0.05) concentrations of crude fibre, neutral detergent fibre, acid detergent fibre, acid detergent lignin, saponin, tannins, phytate, oxalate, and hydrogen cyanide compared to the biodegraded maize cobs. Experiment 2 involves the measuring of in vitro gas production and gas production characteristics of Non biodegraded maize cobs and Biodegraded maize cobs. The biodegraded maize cobs produced significantly more (P<0.05) gas than the non-biodegraded maize cobs, particularly in the 6-24 hour incubation period. The biodegraded maize cobs also produced higher (P < 0.05) values ofin vitro organic matter digestibility, in vitro dry matter digestibility, short chain fatty acids, and metabolisable energy. The Pleurotus tuber-regium biodegraded maize cobs were more digestible and had more energy available for the body to use. The proximate assay, anti-nutrients and mineral composition of experimental diets composed of graded levels of best biodegraded maize cobs were determined in experiment 3. The findings showed that the CP, and ash were significantly (P <0.05) high in Diets and Diet). CF, NDF and ADF showed significant (P<0.05) decrease with increasing levels of PTRMC. The minerals showed significant differences, with calcium and potassium increasing with increasing amounts of PTRMC. The other minerals, phosphorus and sodium, differed (P <0.05) significantly, but the differences did not follow a clear pattern. The saponins, tanins, phytates, oxalate, hydrogen cyanide and alkaloids levels were significantly (P<0.05) reduced in Diet). In vitro gas production and fermentation characteristics of the experimental diets were explored in experiment 4. The results showed that the in vitro gas production volumes were significantly (P <0.05) higher for Diet3 and Diet4 between 9 and 24 hours of incubation period. OMD, SCFA and ME were significantly (P <0.05) increased with increased levels of PTRMC, the CH4 significantly (P <0.05) decrease with increased levels of PTRMC the diets while invitro dry matter digestibility (IVDMD) did not follow a clear pattern. Feeding trial was conducted in experiment 5 with 16 WAD goats averaging 5.28 kg in weight were randomly divided into four groups of 4 goats each. The groups were randomly assigned to four experimental diets (Diet,, Diet2, Diets, and Dit/j) for 90 days in a completely randomized design. The results showed significant (P <0.05) differences for feed and DM intakes. Daily weight gain was significantly (p<0.05) improved in Diet3 and Diet4 FCR tended to decrease (P <0.05) with increasing levels of PTRMC in the diets. Packed cell volume and red blood cells were better (P <0.05) in Diet4 in comparison with other treatments diets. Lymphocytes were significantly higher in Diet4 and 2 while Neutrophils differed significantly with no pattern. Cholesterol and urea values were higher (P <0.05) in (Diet 1, 2 and 3) and also show similarity with (Diet2, 3 and 4). Creatinine, Total protein, globulin, Albumin total bilirubin were higher (p<0.05) in Diet2 and Diet3. ALT was higher (P <0.05) in Diet3 and 4. Warm carcass weight, dressing percentage, loin, set and shoulder weights were significantly (P <0.05) increased at Diet3 and Diet4. Nutrient digestibility and nitrogen balance studies using graded dietary levels of PTRMC (0%, 15%, 30%, or 45%) in experiment 6, four bucks were used in the digestibility and nitrogen balance study in a 4 x 4 Latin Square Design. Results showed that dry matter, crude protein, crude fibre, NDF and ADF were better (P<0.05) digested in Diet4 group. Nitrogen intake was higher (P <0.05) in Diet4 (17.24 g/d) and lowest in Dieti (9.87g/d). Nitrogen balance, nitrogen retention and nitrogen absorbed were significantly (P <0.05) higher for goats on Diet4. It could be concluded that the use of Pleurotus tuber regium for the biodegradation improved the quality and feeding value of maize cobs. Incorporation of PTRMC in diets of WAD bucks generally enhanced performance, blood profile, nutrient digestibility, nitrogen balance and dressing percentage. Diet4 promoted the best relative performance among the treatment diets and is therefore recommended for production of goats in the tropics.