PERFORMANCE CHARACTERISTICS OF BROILER CHICKENS FED GRADED LEVELS OF ONION (Allium cepa) AND ONION WITH BACTOFORT

ABSTRACT
 
Two feeding trials were conducted to evaluate growth performance, carcass characteristics, nutrient digestibility, haematological and serum biochemical parameters of broiler chickens fed graded levels of onion (Allium cepa) and onion with Bactofort^® as eubiotics. Two hundred and forty (240) day old Ross 308 strain broiler chicks were allotted into five different dietary treatments with 0, 100, 200, 300 and 400g Allium cepa levels/100kg diet in the first experiment and 0, 15, 30, 45 and 60g Bactofort^® levels added to 200g Allium cepa/100kg diet in the second experiment. Each treatment had 16 birds per pen replicated three times in a completely randomized design. Feed and water were given ad libitum while vaccination and other daily routine managements were duly observed throughout the experimental period. Data collected were subjected to analysis of variance using Statistical Analysis System and means were compared using Dunnett’s package. Results of the first trial showed an insignificant (P>0.05) difference in performance parameters measured during starter period. At the finisher phase, final body weight (2137.47 – 2223.25g) and weight gain (1462.05 – 1548.10g) were significantly (P<0.05) higher in treatments receiving Allium cepa additions compared to the control (0g Allium cepa addition level) which had 2121.53g and 1445.53g respectively while feed intake and feed conversion ratio (FCR) were similar. Mortality was also higher in the control compared to Allium cepa treatment groups. 200g Allium cepa addition level had significantly (P<0.05) higher live weight (2191.78g), dressed weight (1541.11g) and dressing percentage (75.16%) compared to the other treatment groups. However, there were no significant (P>0.05) differences in all haematological and serum biochemical indices across the treatments except for albumin, creatinine, aspartate aminotransferase, alkaline phosphatase and total cholesterol. Percent