Feeding value of defatted cashew kernel as an alternative protein source in broiler diets
This study was carried out to determine chemical composition of defatted cashew kernel cake (CKC) and cashew kernel oil (CKO), assess performance characteristics and nutrient digestibility of broiler chickens fed diets containing two grades of CKC. In the study, 210, one-day old Arbor acre broiler chicks which were stabilized on commercial diets (23% CP and 2900kcal/kgME) for 2 weeks before introduced to the seven experimental diets were used. The experiment was laid out in a 2 x 3 factorial arrangement which consisted of a control treatment without CKC while treatments 2, 3, 4 and 5, 6, 7consisted of 33.33%, 66.67% and 100% replacement of groundnut cake (GNC) with grade I and grade II CKC respectively. Digestibility trial was carried out at the end of eighth week of the study. Data on performance attributes and coefficient of nutrient digestibility were collected and analysed using a general linear model of SAS. The results of proximate composition showed no substantial difference in dry matter, crude protein, soluble and insoluble carbohydrate except ether extract. Caloric content in CKC was slightly higher than GNC. Both physical and chemical properties of the defatted cashew oil were similar to that of groundnut. The performance traits measured in terms of body weight gained, total feed intake and feed conversion were significantly (P<0.05) different across the treatments with birds on CKC showing superior performance than birds on GNC diet with 17.72% and 13.35% higher BWG in grade I and II respectively. Fat deposition was notably (P<0.05) higher in birds on CKC diets. Digestibility of nutrients indicated that the dry matter, crude protein, ether extract and crude fibre digestibility were significantly (P<0.05) affected across the treatments by the inclusion of CKC in the diets, while the Ash and NFE digestibility were not significantly (P>0.05) influenced. Economically, the use of CKC reduced the heightened cost of production by 9.1%. It can be concluded that grade I CKC could completely and favourably replace GNC in diets of chicken to improve growth, feed efficiency and to reduce the cost of feed per unit egg.