Field Evaluation of vaccines against Respiratory viral disease in chickens

摘要

In modern poultry industry, vaccination is the backbone for prevention of avian respiratory viruses parallel with strict hygienic measures such as good ventilation, proper stocking density, hygienic disposal of carcasses, and control of ammonia gas. Vaccination regimen against these viruses vary from one to another as it was found that in Avian Influenza it could be prevented by only inactivated vaccines against subtype specific strain. On the other hand in case of Infectious Laryngotracchitis, only live vaccine is used and immune response produced mainly cellular immunity, while in case of Infectious Bronchitis it depends mainly on Protect-type phenomena taken in consedration the recommendation of using of different vaccinal strains start with classical parent one. In Newcastle disease, we depend on both live and inactivated vaccines parallel with serological monitoring using Haemagglutination Inhibition test for choose proper time of vaccination. Reo virus vaccine was used only in breeders with four times doses two live and two inactivated vaccinal doses. In case of swollen head syndrome; vaccinations occurs only in breeders with two doses one live for priming followed by second inactivated one together with good hygienic measures. Field evaluation of viral respiratory vaccine is a field mirror for either vaccination success or failure which reflects on bird survival. Moreover vaccination success depend on different factors including type of vaccine used, route of application, age of bird, time of application, concomitant disease condition as well as type of production. Viral respiratory diseases cause severe economic losses among poultry industry and strict vaccination regimen should be applied in order to prevent infection.