Abstract Title
Egg drop induced by H9N2 low pathogenic avian influenza virus infection can be controlled using a single recombinant turkey herpesvirus vaccine in layers
Abstract
Low pathogenic avian influenza virus (LPAIV) of the H9N2 subtype became one of the most important viral diseases of poultry due to the economic losses related to drop in egg production in layers and the respiratory disease accompanied by increased mortality in the presence of co-infections in broilers. One of the most prevalent group of H9N2 strains in poultry is the G-lineage.
Vaccination is used to help controlling the disease, in addition to sanitary measures. Killed vaccines require repeated administrations in layers to cover their lifetime. Turkey herpesvirus vectored vaccine (rHVT) also became available against a wide range of poultry pathogens, which technology is already proven to induce long duration of immunity after a single vaccination.
In our study, commercial layers were vaccinated either at day-old with a novel rHVT-ND-H9 vaccine (against LPAI H9 and Newcastle disease), or 3-times with a killed ND H9 vaccine or kept unvaccinated. Protection against egg drop was tested at 40 and 47 weeks of age using a H9N2 (G) challenge strain from Asia and North Africa, respectively. A significant drop of egg production was observed in controls, whereas both groups of vaccinated hens showed significant protection, regardless the challenge strain.
The results show that rHVT vaccine can be an alternative to killed vaccines to control the egg drop in layers after H9N2 infection, while improving welfare and simplifying the vaccination program.
Vaccination is used to help controlling the disease, in addition to sanitary measures. Killed vaccines require repeated administrations in layers to cover their lifetime. Turkey herpesvirus vectored vaccine (rHVT) also became available against a wide range of poultry pathogens, which technology is already proven to induce long duration of immunity after a single vaccination.
In our study, commercial layers were vaccinated either at day-old with a novel rHVT-ND-H9 vaccine (against LPAI H9 and Newcastle disease), or 3-times with a killed ND H9 vaccine or kept unvaccinated. Protection against egg drop was tested at 40 and 47 weeks of age using a H9N2 (G) challenge strain from Asia and North Africa, respectively. A significant drop of egg production was observed in controls, whereas both groups of vaccinated hens showed significant protection, regardless the challenge strain.
The results show that rHVT vaccine can be an alternative to killed vaccines to control the egg drop in layers after H9N2 infection, while improving welfare and simplifying the vaccination program.
Co-Author(s)
E. Walko-Kovacs1, T. Tatar-Kis1, B. Felfoldi1, Z. Homonnay1, I. Kiss1, M.S. Sandikli2, C. Cazaban2
1: Ceva Animal Health, Budapest, Hungary; 2: Ceva Animal Health, Libourne, France.
Abstract Category
Diagnostics, vaccination, or other mitigation strategies for poultry and wildlife