A New Vaccine to Fight Poultry Diseases

By Sandra Avant
March 20, 2015

A vaccine that protects chickens against two infectious poultry diseases has been developed by U.S. Department of Agriculture (USDA) scientists.

Microbiologist Qingzhong Yu and his colleagues at the Agricultural Research Service's Southeast Poultry Research Laboratory (SEPRL) in Athens, Georgia, created a vaccine that is effective against infectious laryngotracheitis (ILT) and Newcastle disease (ND). ILT and ND are two of the most economically important infectious diseases of poultry. They cause sickness and death in domestic and commercial poultry as well as in some wild birds throughout the world.

By using reverse genetics technology, Yu was able to generate new dual vaccines by inserting a gene from the infectious laryngotracheitis virus (ILTV) into the Newcastle disease virus (NDV) LaSota vaccine strain, which has been used for more than 50 years to protect poultry from ND.

Vaccines were tested in more than 100 1-day-old chickens and 120 3-day-old commercial broilers. All vaccinated birds were protected against both ILTV and NDV challenges. They showed little or no clinical signs and no decrease in body weight gains. Vaccines were found to be stable and safe in chickens of all ages.

According to Yu, the new vaccines are safer than the current live-attenuated ILT vaccines. They can be safely and effectively given by aerosol or drinking water to large chicken populations at a low cost.

ARS is USDA's principal intramural scientific research agency, and this research, which was published in the Journal of Virology, supports the USDA priority of promoting international food security.

Read more about this work in the March 2015 issue of Agricultural Research magazine.