Comparative evaluation of biofilm and free cell oral vaccines against Escherichia coli in broiler chicks*
Abstract
A preliminaty vaccination trial in chicks was carried out to evaluate and compare the protection pattem conferred by killed biofilm and free cell oral vaccines using E. coli (078) serotype. Chicks were fed daily with killed vaccine (10° CFU) after mixing with feed from day three to day eight of the experiment and booster dose of vaccine was given from day 21 to 23 of the experiment. A maximum of 83.3 percent protection was observed in biofilm vaccinated group after challenge infection, whereas only 33.3 and 16.6 percent protection was observed in free cell vaccinated and unvaccinated group of chickens respectively.
Keywords
Oral vaccine, E. coli, biofilm
