A bivalent vaccine against avian necrotic enteritis and coccidiosis.

Abstract

In this study, we attempted to design a recombinant vaccine harbouring domain with a key role in enterocyte attachment and cell invasion in necrotic enteritis (NE) and coccidiosis. In this study, we investigated whether a recombinant protein consisting of necrotic enteritis B-like toxin, C-terminal domain of alpha-toxin, apical membrane antigen 1 (AMA1), and Rhoptry neck protein 2 (RON2) which we call "NeCoVac" hereafter, can improve protection against both diseases compared to vaccination with each antigen in previous studies. Birds intestinal lesion scores and specific antibody levels were measured to determine protection after oral gavage challenges with virulent Clostridium perfringens and LIVACOX® T. Birds immunized with NeCoVac were protected up to 84% against NE and coccidiosis compared to unimmunized and even positive groups (groups treated with LIVACOX® T [coccidiosis live vaccine] and tylosin as routine veterinary interventions) (p<0.05). Our findings suggest that vaccination with NeCoVac is highly efficient in protecting birds from NE, coccidiosis and a combination of both diseases. The present study is the first one to describe the combinatorial use of AMA1 and RON2 against coccidiosis, and the first report using NeCoVac against NE and coccidiosis together.