Evaluation of Live Vaccine Application in Commercial Poultry Flocks Using Feathers - In Practice.

Protection against diseases caused by avian viruses is achieved by vaccination with different forms of vaccines, the best protection being attained using live vaccines. The live vaccine application is a very complex procedure that receives marginal attention, in spite of its crucial importance for vaccination success. As a result of our recent development focusing on the vaccine uptake evaluation using feathers, we put in practice that methodology in order to answer reservations regarding the vaccine application in several commercial flocks following vaccination. The present study describes five conundrums concerning Marek's Disease vaccination and four conundrums regarding Infectious laryngotracheitis (ILTV) vaccination, demonstrating the power and usefulness of this new approach to monitor vaccine application. We were able to detect various operational situations, including improper calibration of the Marek's disease virus (MDV) vaccination device, improper administration of the ILTV vaccine in drinking water, however we also demonstrated cases where adequate MDV vaccinations of various flocks were performed. Each case was described separately regarding the specific problem, the examination details and the conclusions drawn following the vaccine virus uptake in the feathers of the commercial chickens. [ABSTRACT FROM AUTHOR]