ENHANCEMENT OF THE NUTRITIVE VALUE OF COMPOSITE COCOA (Theobroma cacao) POD HUSK FOR WEST AFRICAN DWARF GOAT PRODUCTION

Abstract

The ‘wastes’ of agricultural produce is increasingly been viewed as a source of alternative feed ingredients for ruminants in spite of the comparatively lower protein and high fibre which makes their digestibility low. This necessitated the need to improve their nutritional quality. Thus, five interrelated experiments were conducted to evaluate the nutritive potentials of composite cocoa pod husk in goats’ production with a view to nutritionally upgrade the pod as alternative feedstuff in goat nutrition. Cocoa pod husks were sundried, milled, soaked in water, cocoa pod ash solution (lye), and 5% urea solution for 7 days, decanted and ensiled for 28 days under anaerobic conditions. Thereafter, they were analysed for their proximate composition, gross energy, minerals and antinutritional factors. The nutritive potentials of the test diets were evaluated through in vitro gas production and in vivo techniques. The raw and the differently treated pod were incorporated into the diets of West African Dwarf (WAD) goats, to substitute for cassava peels to evaluate their response, and the best treatment (from the characterization with respect to highest crude protein level, least crude fibre, phytate, alkaloid and theobromine) were used to replace cassava peels at 0, 10, 15, 20, 25 and 30% in diets of WAD does in a 90 day feeding trial, using four does per replicate in a completely randomized design experiment. Parameters assessed included: nutrients, minerals, energy and anti-nutrient compositions of the experimental diets, total gas production, short chain fatty acid, organic matter digestibility, metabolizable energy, nutrient and anti-nutrient intake, digestibility, nitrogen utilization, growth performance, haematological and serum biochemical indices of the goats. Results showed that all parameters assessed were significantly (P<0.05) influenced by the dietary treatments. The crude protein (CP) contents of the pod increased from 8.31% (raw CPHM) to 14.28% (urea-treated CPHM), reduced the crude fibre (23.91 - 33.87%) and antinutrients- alkaloid (3.45 – 6.50%) and theobromine concentration (2.05 – 3.89%) respectively. In vitro study revealed that; urea-treated CPHM had nutritional potentials for ruminants. CH4, ME, SCFA, OMD and IVDMD values were highest in 30% cassava replaced - urea-treated ensiled CPHM. The daily weight gain of goats fed 10% inclusion level of urea-treated CPHM (26.56g/d) was best compared to 10% inclusion levels of raw (9.22g/d), water (14.44g/d), lye (21.10g/d) and poultry droppings (20.78g/d) treated CPHM. The DMI (449.84g/d), CPI (63.53g/d), nitrogen balance (8.94g/d) and daily weight gain (32.99g/d) of does fed 30% UTCPHM diets were significantly (p<0.05) higher than those fed other test diets. More so, they have the highest value of PCV (29.51%), RBC (10.02 x106μl), Hb (11.27g/dl) and the AST levels were within the normal range recommended for healthy goats. Generally, the health status of the goats was not compromised as indicated in the values of the haematological and serum biochemical indices. It can be concluded that composite cocoa pod husk, if treated with urea, could favourably be used as an alternative feed ingredient for WAD goats. Majorly as an energy source to replace cassava peel, even up to 30% level in their ratio. Thus, the method could be adopted by ruminant farmers.