Performance, apparent nutrient digestibility responses and the economics of feeding Nigerian rice milling by-products to weaner rabbits

Abstract

An eighty-four (84) day feeding trial was conducted to evaluate the effect of feeding rice milling by-products (rice offal, rice bran and rice grain rejects) on growth performance and production economics of crossbred (New Zealand white X Chinchilla) weaner rabbits with mean live weight of 347g. The rabbits were randomly allotted, 5 each, to five experimental diets, with each animal serving as a replicate. The diets were designated D1, D2, D3, D4 and D5. Diet D1 contained no rice milling by-products and served as the control, D2 contained 20% rice offal, D3 20% rice bran, D4 20% rice grain rejects and D5 10% rice bran + 10% grain rejects. Feed and water were provided ad-libitum. Daily feed intake, daily weight gain and feed conversion ratio (67.94-79.42g, 13.50-15.97g, and 4.71-5.67 respectively) were not affected (p>0.05) by inclusion of rice milling by-products in the diets. Apparent nutrient digestibility indices, except for Nitrogen Free Extract (NFE), were also not influenced (p>0.05) by treatments. NFE digestibility was depressed by the feeding of rice offal (p<0.05). Feed cost per kg of weight gain was highest for the rabbit fed the control diet (₦587/kg) and lowest (p<0.05) for those on diet containing rice bran (₦436/kg). Gross margin between total production cost and revenue was highest for rabbits fed a combination of rice bran and rice grain rejects(₦701.18/rabbit), and lowest (₦561.62/rabbit) for the diet that contained no rice milling by-products. It was, therefore, concluded that the use of these rice milling by-products can be recommended for meat rabbit production. However, further studies should be carried out to elaborate the chemical properties and feed potential of this class of feed ingredients.

Key words: Feed intake, weight gain, Feed conversion ratio, Nutrients digestibility, Rice milling by-products