Study: Newcastle Disease protection for at least 60 weeks

Innovax-ND and Innovax-ND-SB, two one-dose recombinant vaccines widely used by the US poultry industry, have been shown to aid in the protection of Newcastle disease for at least 60 weeks, according to a study recently accepted by the United States Department of Agriculture.

“This study confirms that the vaccines provide lifelong protection against the world’s most prevalent poultry disease in broilers, as well as long-lived birds such as broiler breeders and layers,” said Charlie Broussard, DVM, US poultry technical service director for Merck Animal Health, which developed and markets the vaccine.

In the study, researchers administered Innovax-ND subcutaneously to 1-day-old specific-pathogen-free chickens before challenging them with a very virulent ND virus at 20, 40, 50 or 60 weeks of age. They observed the birds for 10 days after each challenge. Chickens were considered negative if they remained free of clinical ND signs.

Chickens vaccinated
All chickens vaccinated with Innovax-ND were protected against every challenge conducted; in contrast, all chickens in an unvaccinated group that were challenged at the same times as the vaccinated chickens developed ND. This research was conducted by Lillian Melson and Karen Jensen of Merck Animal Health, who presented their findings earlier this year at the 1st International Avian Respiratory Disease Conference in Athens, Georgia.

“The data from this study demonstrate that Innovax-ND and its sister product, Innovax-ND-SB, provide protection against a very virulent Newcastle disease challenge for at least 60 weeks post-vaccination,” Broussard said.

Recombinant vaccine
Launched in 2010, Innovax-ND is a recombinant vaccine that eliminates the need for stress-causing, oil-based, inactivated BD vaccines. It also can replace conventional, live ND vaccines, which are associated with rolling reactions, as well as added time and labor costs when they are applied in the field. The vaccine can be administered in ovo to 18-day-old embryos or subcutaneously to 1-day-old birds.

Innovax-ND-SB, which has been available since 2008, helps prevent ND and Marek’s disease, but also contains the SB-1 strain of chicken herpesvirus (serotype 2) to prevent very virulent Marek’s. Innovax-ND-SB is approved for in ovo administration only.

Both vaccines utilise the turkey herpes virus (HVT) as a vector or carrier for the ND virus that stimulates immunity against ND; HVT is well recognised as a safe virus for chickens and also protects against Marek’s disease, another serious herpesvirus disease of poultry that can result in widespread morbidity and mortality.

Source: Merck Animal Health