Abstract

Two commercial types of Hydro pericardium Hepatitis Syndrome (HHS) oily inactivated vaccines were evaluated. The first was (Angavac) French in origin (Merial Co.) & the 2nd is (Nobilis Hepatitis) Holland in origin (Intervet Co.). A unified program of vaccination had been used for both vaccines. One & ten days old chicks were vaccinated by subcutaneous & intramuscular route of injection with both vaccines in each age separately . Serum antibodies titer weekly measured by using Indirect haemagglutination test (IHA) & agar gel diffusion test. Challenge test at 4 week of age was done by virulent avian adeno virus serotype – 4 (VAAV-4) as well as virulent field isolate was used as challenge virus. The result showed highest antibodies titer at week age. Angavac vaccine gave highest titer than Nobilis Hepatitis vaccine & IHA was more sensitive than AGDT. All groups vaccinated with Angavac gave 100% protection in challenge test with (VAAV-4) at 28 days. While in Holland vaccine the protection ratio was 60-80% only, but the ratio of protection of both vaccines did not exceed than 40-50% when the field isolate was used as challenge virus.