Potential and safety tests of egg drop syndrome candidate vaccine from Medan isolate, Indonesia

Abstract Aim: The study was aimed to prepare and examine the potential and safety concerns of egg drop syndrome (EDS) vaccine candidate seed. The potential and safety trials of EDS Medan isolate vaccine need to be done before commercial scale of EDS vaccines are made. Materials and Methods: The safety test of EDS candidate vaccine was tested on 4-week-old specified pathogen-free chickens in an experimentally isolated enclosure. Results: The result of the safety test obtained 2 hemagglutination inhibition (HI) unit of geometric mean titer antibody post-vaccination. However, the potency test of the EDS candidate vaccine was conducted on 17-week-old laying hens. Test results of the EDS potency vaccine in layer obtained antibody titer increased in every week of blood taking with average titer of antibody: Before vaccinated was 2.9 log 2 HI unit, 1 week after vaccination was 7.3 log 2 HI unit, 2 weeks post-vaccination was 5 log 2 HI unit, and 3 weeks after vaccination was 7.3 log 2 HI units. In contrast, decreasing trend was observed in control group (unvaccinated chicken). Conclusion: Serologically, the seed vaccine of EDS virus isolates from Medan was able to produce protective antibody titers starting in the 2nd and 3 weeks post-vaccination. Keywords: hemagglutination, inhibition test, Medan isolate, safety and potential test, seed of egg drop syndrome vaccine.