Growth performance and immunological responses of broiler chickens fed synbiotics and diet acidifiers to Newcastle disease vaccinations
This study was conducted to determine the growth performance and immune response of broiler chickens fed synbiotic and diet acidifier to Newcastle disease vaccinations. One hundred and forty four (144) day old broiler chickens were randomly assigned to four dietary treatments replicated thrice with 12 birds per replicate. Diet I served as the control, diet II had inclusion of dietary synbiotic, diet III contained diet acidifier while diet IV had inclusion of both synbiotic and acidifier. A regimented Newcastle disease (ND) vaccination programme was carried out. The results showed that the performance characteristics measured- final body weight (FBW), total weight gain (TWG), total feed intake (TFI) and feed conversion ratio (FCR) were significantly influenced (p<0.05) by the dietary treatments at different ages of the birds. The birds fed diet with inclusion of acidifier had highest FBW (2326.37g), TWG (2284.57g) and TFI (5858.49g) at the end of the feeding trial. The immunological response of experimental birds to ND vaccinations was not significantly different (p>0.05) among dietary treatments. The antibody titre values of birds fed diet III and IV were the highest (log27 and log28) after the first and second ND vaccinations compared to those given other test diets. The haematological parameters measured did not differ significantly (p>0.05) among treatment groups. It was concluded that inclusion of dietary acidifiers in feed of broiler chickens enhanced productive performance and improved the immune response to ND vaccinations.