Zoetis expanded its poultry vaccine portfolio with Poulvac Procerta HVT-ND, a vectored recombinant vaccine that protects broiler chickens against Newcastle and Marek’s disease viruses, with its introduction at the January 2020 International Production and Processing Expo (IPPE) in Atlanta.
“Poulvac Procerta HVT-ND is the first Zoetis vaccine developed with our state-of-the-art vector platform and is the newest of its kind available,” said Jon Schaeffer, D.V.M., Ph.D., senior director of U.S. poultry technical services for Zoetis. “The vaccine was developed using advanced molecular techniques to deliver a highly effective immune response, with competitive onset of immunity.”
Researchers focus on early onset of immunity
Newcastle disease (ND) virus causes a highly contagious and fatal disease affecting all species of birds. Zoetis researchers screened more than a dozen vaccine candidates with the ND virus fusion protein — a major glycoprotein present in the viral envelope and one of the main immunoprotective ND virus antigens.
The candidate they ultimately selected for Poulvac Procerta HVT-ND provided 93 percent protection against a challenge with velogenic (virulent) ND virus on day 19 of age and 95 percent protection against a velogenic ND virus challenge on day 28 of age in specific-pathogen-free birds, regardless of whether the vaccine was administered in ovo or subcutaneously. When the vaccine was administered in ovo to commercial broilers, there was 100% efficacy against a velogenic ND virus challenge on day 33 of age, according to Zoetis.
Poulvac Procerta HVT-ND contains the herpesvirus of turkey (HVT), an avirulent turkey virus that is capable of replication in chickens. HVT has been demonstrated as a useful vector for delivering major avian antigens, as well as an effective vaccine for Marek’s disease virus.
More than 20 years of in ovo expertise
Poulvac Procerta HVT-ND has began shipping in January 2020. Nearly 70% of U.S. broilers were immunized in 2018 with a vectored vaccine, according to market research conducted by Rennier Associates Inc.
“Building a robust immune system through vaccination is particularly critical today with the rise in ‘no antibiotics ever’ broiler production,” Schaeffer said. “By providing foundational immunity to ND without the reaction of a live ND vaccine, Poulvac Procerta HVT-ND helps enable the success of live infectious bronchitis (IB) vaccination programs.”