Nutrient Digestibility, Carcass Yield and Production Economics of West African Dwarf Goats Fed Pleurotus Tuber-Regium Biodegraded Rice Straw and Maize Offal-Brewer Yeast Slurry Mixture

This study was conducted to evaluate the effect of feeding Pleurotus Tuber-regium biodegraded rice straw (PTTRS) and maize offal-brewer yeast slurry mixture (MOBYS) on nutrient digestibility, carcass yield and production economics of West African Dwarf Goats. Twenty four WAD goats, allotted to six groups of four goats per treatment in a completely randomized design were used in the study. The six dietary treatment groups were fed varying levels of MOBYS, and ad libitum, untreated rice straw (UTRS) and Pleurotus tuberregium treated rice straw (PTTRS) thus: T1= 100 g MOBYS and UTRS ad libitum, T2=100 g MOBYS and PTTRS ad libitum, T3=200 g MOBYS and UTRS ad libitum, T4=200 g MOBYS and PTTRS ad libitum, T5=300 g MOBYS and UTRS ad libitum, and T6=300 g MOBYS and PTTRS ad libitum in an experiment that lasted for 90 days. In the last week of the study, two goats per treatment were transferred to metabolic cages for digestibility study. Weighed quantities of the feeds and water were offered to the goats on a daily basis, and faeces were collected and dried. At the end of seven days, the faeces were oven dried to constant weight and then bucked by treatment and samples sent for proximate analysis. Apparent nutrient digestibility coefficients were calculated using results of proximate analysis of the faeces. After the 90 days feeding period, two animals from each treatment were selected and used for carcass analysis. They were fasted for 24 hours during which they were given plenty drinking water, and sacrificed by severing the jugular vein, bled and the following carcass cuts obtained: neck, shoulder, flank, loin, rib and thigh. The following carcass by products and visceral organs were also obtained: head, feet, skin, empty gut, abdominal fat, heart, lungs, liver, kidney and spleen. The economics of production was assessed using the net farm income (NFI) budgeting technique based on cost of feed consumed, feed cost per weight gain, cost of goat purchase, total variable cost, sale value of goat and income from goat sale. Based on the results obtained, it was concluded that combined feeding of the test inputs to the WAD goats enhanced nutrient digestibility, resulted in normal carcass characteristics and offal as well as considerable reaping of economic benefits depending on the levels of the test materials fed.

Keywords: Nutrient-digestibility; carcass-yield; production-economics, goats, rice-straw, brewer-yeast-slurry; maize-offal;