Zoetis has introduced Poulvac Procerta HVT-IBD-ND, a recombinant vector vaccine that provides early, robust protection against Marek’s disease (MD), infectious bursal disease (IBD), and Newcastle disease (ND) viruses with one dose.
Dr Sing Rong, Zoetis Research Director, said the new vaccine is the culmination of meticulous research conducted by a team of the company’s top molecular scientists using the most advanced technology available.
“The vaccine has a unique construction and a strong promoter that helps boost immunogenicity — features that set it apart from other vaccines in the same category,” she said.
The backbone of the new, trivalent vaccine is avirulent herpesvirus of turkey (HVT), which replicates in chickens and is known to be a safe and effective vector for delivering major avian antigens. It is the third recombinant vector vaccine from Zoetis, following the introduction of Poulvac Procerta HVT-ND in 2020 and Poulvac Procerta HVT-IBD in 2021.
When developing the vaccine, Zoetis scientists started by constructing 43 recombinant prototypes, which were then subjected to rigorous, controlled studies to find the one that provided the best, early immunity. The candidate that was finally selected is the vaccine that is now Poulvac Procerta HVT-IBD-ND.
Onset of immunity
Protection in birds that received the trivalent vaccine in-ovo was 90% following intraocular challenge with a virulent IBD virus at 14 and 21 days of age, Dr Rong said.
The vaccine also proved effective against velogenic ND following in-ovo administration, providing 75% protection after a challenge at 14 days of age and 95% protection after challenge at 21 days of age.
When birds that received Poulvac Procerta HVT-IBD-ND were challenged at 63 days of age with virulent or very virulent IBD or velogenic ND viruses, 100% were protected, demonstrating the vaccine’s long duration of immunity, Dr Rong said.
Like the other HVT vector vaccines, Poulvac Procerta HVT-IBD-ND has an excellent safety profile and avoids reactions associated with live ND vaccines. It can be administered subcutaneously at hatch as well as in-ovo, she added.
Cuts losses, labor costs
According to Dr Kalen Cookson, Zoetis Director of Clinical Research, the ability to protect against three diseases with one dose has several advantages.
“Most important is the early protection the vaccine provides, which can help prevent costly losses associated with all three diseases,” he said.
“MD, IBD and ND viruses are contagious pathogens that lead to poor field performance and condemnations. MD and IBD lead to immunosuppression, which predisposes both young and older birds to secondary infections. Establishing early, robust immunity through vaccination is essential,” Dr Cookson continued.
In addition, he said, “the high ND protection levels provided by Poulvac Procerta HVT-IBD-ND persist even in the oldest broilers raised today, in contrast to the more short-lived immunity provided by single applications of live ND vaccines.”
A trivalent vaccine simplifies vaccine preparation, and when administered with proven technology such as the Embrex Inovoject system, producers can save a considerable amount on labor, he added.