High dietary marula (Sclerocarya birrea subsp. caffra) seed (nut) cake induces detrimental effects on performance, carcass characteristics and immuno- physiology of broiler chickens

Abstract

AbstractBackground The objective of this study was to investigate effects of dietary incremental levels of marula seed cake (MSC), partially replacing soya bean meal (SBM) on growth performance, carcass characteristics, and haemato-biochemistry of broiler chickens from starter to finisher phases. In a completely randomized design, 400 day-old Ross 308 broilers were randomly allotted to 5 diets with 0, 5, 10, 15 and 20% MSC, each with 8 replicates of 10. Weekly feed intake, body weight gain and feed conversion efficiency were calculated whilst haemato-biochemistry was measured at d42. Results Overall, feed intake was quadratically decreased (P < 0.01) by MSC, of which the optimum inclusion was 15%. Body weight gain and feed conversion efficiency was linearly decreased (P < 0.001 andP < 0.01, respectively) by dietary inclusion of MSC. Also, MSC linearly decreased slaughter weight (P < 0.001), hot carcass weight (P < 0.001) and cold carcass weight (P < 0.001). Similarly, it linearly decreased white blood cells (P < 0.01) and lymphocytes (P < 0.05) and symmetric dimethylarginine (P < 0.001), as it linearly increased (P < 0.001) serum cholesterol. Conclusion In conclusion, up to 15% MSC can be incorporated into broiler diets in replacement of SBM without adverse effects.