Nucleocapsid of rabies virus improve immune response of an inactivated avian influenza vaccine

The purpose of this study was to determine if nucleocapsid of rabies virus could improve the immune response (humoral and protective) of chickens vaccinated against avian influenza with an inactivated avian influenza experimental vaccine (AIV). On the other hand, AIV with and without NC was compared with an inactivated oil emulsion avian influenza commercial vaccine (CV) virus, currently used in Mexico. Groups of 8 day old chickens were vaccinated intracutaneously with an AIV (group 1); group 2, AIV supplemented with 20 μg of nucleocapsid of rabies virus (NC); Group 3, commercial vaccine (CV) and control groups (4 and 5) with 20 μg of NC and non-infected allantoic fluid, respectively. CV showed a better antibody-mediated response (p < 0.001) after and before challenging; which correlated with the best protection; while NC improved the protection in comparison with group 1. This is the first report on the potential utility of the rabies virus N protein to improve immune response in domestic species.