Vaccination against NDV in turkeys infected by haemorrhagic enteritis virus [Polish]

摘要

The purpose of the study was to determine the influence of infecting turkeys with a local isolate of HE virus on their post-vaccination response to NDV. The study was carried out on 60-day old turkeys, 50 of which were intravenously infected with HEV at a dose of 10(3,6)EID(50) on the 49(th) day of life. Twenty turkeys were immunized simultaneously against NDV and twenty other birds were immunized against this virus 7 days later with Sotasec vaccine in drinking water. Ten infected turkeys and ten uninfected turkeys were control groups for infection and vaccination respectively. Blood from all the turkeys was taken on the day of infection and vaccination and after 7, 17, 27, and 41 days. The serum contained significant levels of HI antibodies. it was demonstrated that the local isolate of HEV causes immunosuppression and this was expressed by a lower efficacy of the vaccine against NDV, especially in the case of the birds immunized 7 days following infection.