Dietary Dialium guineense stem-bark supplementation improves growth performance and haemato-biochemical characteristics of broiler chickens

Poultry farmers, particularly in developing countries, are concerned about the rising cost of conventional feed additives such as antibiotics. This has sparked a lot of interest in the search for phytogenic feed additives (PFAs) that can be used as alternative to antibiotic growth promoter in chicken diets. Thus, the purpose of this study was to evaluate the chemical composition of Dialium guineensestem-bark (DGSB) one of such PFAs, and its effect of its supplementation on the performance of Ross 308 broiler chickens. Fresh D. guineense stem barks were manually harvested, dried on shade and thereafter milled into DGSB powder. The DGSB was chemically analysed and standard broiler chicken diets were supplemented with DGSB at 0 (T1), 0.5 (T2), 1.0 (T3) and 1.5 (T4) g kg(−1) feed. 200 day-old chicks were raised on starter mash from days 1–21 and finisher mash from days 22–47. Results suggested that DGSB is relatively high in fibre, ash and important phytochemicals. Average daily feed intake (ADFI) responded to incremental levels of DGSB linearly. Maximum ADFI was achieved at 1.5 g DGSB/kg feed. Birds in group T2 recorded the lowest feed conversion ratio (FCR) of 1.90, while those in group T4 had the highest FCR of 2.68. Broiler chickens on 0.5 g/kg feed attained higher (P < 0.05) final live weight (FLW) and average daily gain (ADG). Results indicated that dietary DGSB supplementation influenced aspects of the blood traits of Ross 308 broiler chickens. Results also show that DGSB had a quadratic effect on FLW, ADG, aspects of red blood cell indices, platelets, white blood cells, lymphocytes, glucose, cholesterol, alanine transaminase (ALT) and aspartate transaminase (AST) in broiler chickens. In conclusion, DGSB is high in fibre, ash and some beneficial phytochemicals and may be incorporated to broiler chicken nutrition at a supplementation level not beyond 0.5 g/kg feed for best growth performance and blood characteristics.