EFFECTS OF IN OVO SYNBIOTIC INJECTION ON GROWTH PERFORMANCE, INTESTINAL BACTERIAL LOAD AND ANTIBODY TITRES IN BROILER CHICKENS VACCINATED AGAINST INFECTIOUS BURSAL DISEASE

Abstract

The present study investigated the efficacy of a synbiotic (Lactobacillus delbrueckii subsp. bulgar-icus, Streptococcus salivarius subsp. thermophilus, and mannan oligosaccharide) along with an infectious bursal disease (IBD) vaccine in Cobb 500 broilers. A total of 1200 embryonated chicken eggs were randomly allocated in 10 groups with eight replicates. The first group did not receive any treatment. The second group was vaccinated post-hatch (PV), the third group was vaccinated in ovo (IV), the fourth group received dietary synbiotic and in ovo vaccination (DS+IV), the fifth group was treated in ovo with synbiotic (IS), the sixth group received in ovo and dietary synbiotic (IS+DS), the seventh group received in ovo synbiotic plus post-hatch vaccination (IS+PV) and the eighth group  in ovo and dietary synbiotic and post-hatch vaccination (IS+DS+PV). In the ninth group, the synbiotic and the vaccine were administered in ovo (IS+IV) while the tenth group re-ceived in ovo and dietary synbiotic, plus in ovo vaccine (IS+DS+IV). The in ovo treatment with the synbiotic in combination with DS, IV or PV had a positive effect on weekly weight gain. The sixth group provided a better feed conversion ratio at the end of fourth week. The synbiotic appli-cation, individually in sixth group or along with PV or IV treatment in eighth and tenth groups, elevated feed intake in fifth and sixth weeks respectively.The antibody titre of IBD was higher for groups which received IV along with IS. It is concluded that the application of synbiotic along to IBD vaccine improved growth performance and had positive effects on IBD antibody titres.