Blood Responses of Broilers to Cassava Peel Meal–Palm Oil Sludge Diets
The increasing cost and competition for conventional energy feedstuffs such as maize have intensified the search for locally available agro-industrial by-products for poultry feeding. This study evaluated the effects of graded dietary inclusion of an enzyme-supplemented cassava peel meal–palm oil sludge mixture (CPMPOS+E) on haematological indices and serum lipid profile of broiler chickens. Ninety-six broiler chickens were allotted to three dietary treatments containing 0%, 22.5% and 25.0% CPMPOS+E, respectively, in a completely randomised design. Each treatment was replicated four times with eight birds per replicate. The feeding trial lasted 56 days. At the end of the experiment, blood samples were collected from two birds per replicate for determination of haematological indices and serum lipid profile. Data were analysed using one-way analysis of variance, and treatment means were separated using Duncan’s multiple range test at the 5% probability level. Dietary treatment significantly affected packed cell volume, haemoglobin concentration, red blood cell count, white blood cell count, mean corpuscular volume, mean corpuscular haemoglobin concentration, heterophil percentage, total cholesterol, low-density lipoprotein cholesterol and very-low-density lipoprotein cholesterol (p < 0.05). Mean corpuscular haemoglobin, lymphocyte, monocyte, eosinophil and basophil percentages, triglycerides and high-density lipoprotein cholesterol were not significantly affected (p > 0.05). Total cholesterol decreased from 96.26 mg/dL in the control diet to 92.83 and 93.21 mg/dL in the 22.5% and 25.0% CPMPOS+E diets, respectively. Similarly, LDL-C declined from 17.20 to 15.09 and 13.20 mg/dL. These findings suggest that inclusion of CPMPOS+E at the evaluated levels did not produce broad adverse alterations in the measured blood indices and was associated with lower serum total cholesterol and LDL-C relative to the control. However, the decline in dietary crude protein and metabolisable energy across the experimental diets warrants consideration when interpreting the physiological responses. Further studies using nutritionally isoenergetic and isonitrogenous diets, together with direct determination of residual hydrogen cyanide and nutrient digestibility, are recommended.
Keywords: broiler chickens; cassava peel meal; palm oil sludge; haematology; serum lipid profile; cholesterol; alternative feedstuffs.
