Effect of Maize (Zea mays) Substitution by Sprouted Off-season Sorghum (Sorghum bicolor L. Moench) on the Growth and Physiological Response of Broiler Chickens (Gallus gallus) in Maroua, Far North, Cameroon

With a view to finding an alternative to maize in the composition of poultry feed, a study was carried out to assess the effect of replacing maize with sprouted off-season sorghum on the growth performance and physiological response of broiler chickens at start-up. To achieve this, 180, one day-old chicks of the "Cobb 500" strain with a live weight of 34±3.26 g were randomly divided into 09 batches corresponding to 03 treatments with 3 replicates of 20 subjects. The batches were fed one of 03 rations : 100 % maize (R0), 50 % maize and 50 % sprouted off-season sorghum (R1) and 100 % sprouted off-season sorghum (R2). Every week, feed intake, weight gain and feed conversion ratio were evaluated. At 21 and 42 days of age, carcass characteristics and some haematological and biochemical parameters were assessed. Results showed that feed intake, feed conversion ratio and carcass yield were not significantly affected by the substitution of 50% and 100 % corn by sprouted off-season sorghum. Average daily gain was significantly affected by the substitution of 50 % maize by sprouted off-season sorghum. However, compared with the control ration (100 % maize), the ration containing 100 % germinated off-season sorghum significantly increased the relative weights of the pancreas and proventriculus. Serum levels of transaminase, glucose, total protein, albumin and globulin were not statistically modified when 50 % and 100 % corn were replaced by germinated off-season sorghum. Analysis of haematological parameters showed that the ration containing 50 % maize and 50 % germinated off-season sorghum significantly reduced (p<0.05) red blood cell concentration and significantly increased (p<0.01) mean corpuscular volume (MCV) and mean corpuscular haemoglobin content (MCHC). It can therefore be concluded that corn can be 100 % substituted by sprouted off-season sorghum, without any deterioration in broiler growth performance.