The present study evaluated the efficacy of a vectorized vaccine against Newcastle disease virus (vENC) applied in the hatchery. Two hundred one-day-old chicks were distributed in four experimental vaccination groups against vENC: T1: Live attenuated vaccine + inactivated vaccine, T2: Live attenuated vaccine, T3: Live attenuated vaccine + vectorized vaccine, T4: Unvaccinated control group. All chicks were also vaccinated against infectious bronchitis, Marek and Gumboro viruses at day 1. The birds were challenged on the day 26 with a highly pathogenic field pathogenic strain. Mortality, post-challenge clinical signs, necropsy lesions and antibody response against vENC were evaluated. Chicks vaccinated with the vENC vectorized vaccine had a lower mortality (2%) compared to birds vaccinated with live attenuated strains (12.5% ​​for T1 and 18.4% for T2 respectively; p<0.05). Likewise,...

The present study evaluated the efficacy of a vectorized vaccine against Newcastle disease virus (vENC) applied in the hatchery. Two hundred one-day-old chicks were distributed in four experimental vaccination groups against vENC: T1: Live attenuated vaccine + inactivated vaccine, T2: Live attenuated vaccine, T3: Live attenuated vaccine + vectorized vaccine, T4: Unvaccinated control group. All chicks were also vaccinated against infectious bronchitis, Marek and Gumboro viruses at day 1. The birds were challenged on the day 26 with a highly pathogenic field pathogenic strain. Mortality, post-challenge clinical signs, necropsy lesions and antibody response against vENC were evaluated. Chicks vaccinated with the vENC vectorized vaccine had a lower mortality (2%) compared to birds vaccinated with live attenuated strains (12.5% ​​for T1 and 18.4% for T2 respectively; p<0.05). Likewise,...