Breed effects of three commercial broiler chickens reared in the tropics on performance, carcass, serum and haematological parameters

Résumé

Performance and other parameters of broiler chickens could be influenced by the environment (feeds, housing, climate) and genetic potentials (breeds). Three hundred (300) broiler chicks comprising of one hundred each of the three breeds designated as A, B and C were used in a completely randomized design experiment which lasted for 56 days. Each breed represents a treatment with 5 replicates of 20 birds each. The birds were fed ad libitum with the same commercial starter and finisher diets throughout the period of the study; and water supplied free of choice. Average final body weight, average daily feed intake, average daily weight gain, feed conversion ratio, cost/kg feed and cost of feed/kg live weight gains at the starter and finisher phase were the performance parameters measured. Carcass, serum and haematological indices of these birds were also investigated. Proximate composition of the experimental starter and finisher diets indicated that both were adequately formulated for birds in the tropics under which the study was carried out. Results of the performance parameters showed that the values were similar for the starters and finishers except for highest (P<0.05) feed intake of 134.68g/b/d obtained for breed A compared with 112.01g/b/d and 106.69g/b/d respectively for breeds C and B at the finisher phase. The highest (P< 0.05) cost (N 210.94) of feed per kg live weight gain was obtained for breed A than N 196.10 and N 190.80 respectively for breeds B and C at the starter phase. The average cost of feed per kg live weight (1-8 weeks) were N 282.54, N 270.30 and N 269.28 respectively for breeds A, B and C; with breed C having the lowest cost. The dressed weights were 62.86, 67.29 and 67.84% for breeds A, B and C in the same order. The abdominal fat reduced (P < 0.05) from 1.52% in breed A to 1.02% and 0.77% in breeds B and C. Although the thighs were similar across the breeds, variations in the drumstick, 10.27g/kg breed A, 11.69g/kg breed B and 10.64g/kg breed C differed (P< 0.05). The breast increased (P< 0.05) from 18.62g/kg breed A to 20.36g/kg breed B and 21.95g/kg breed C. Globulin and neutrophils were the only blood indices which differed (P < 0.05) across the breeds at the starter phase. Breed C was considered the best of the 3 breeds in terms of performance, cost, carcass and health status indicated by blood indices; and could be recommended for commercial broiler production for better economic returns.