Assessing the efficacy of a live vaccine against avian encephalomyelitis virus
- 83 Downloads
Avian encephalomyelitis virus (AEV) causes typical neurological symptoms in young chicks and a transient drop in egg production and hatchability in adult laying birds, resulting in huge economic losses in the poultry industry. An effective way to control and prevent this disease is vaccination of the flocks. Here, we assessed the efficacy of the live vaccine candidate strain GDt29 against avian encephalomyelitis virus. The GDt29 strain has low virulence, was confirmed safe, and showed no signs of pathogenicity. High titers of AEV-specific antibodies were detected in GDt29-vaccinated hens (S/P > 3.0) and their progeny (S/P > 2.0). Moreover, the eggs of GDt29-vaccinated hens with high levels of maternal antibodies were hatched successfully regardless of challenge with a heterologous AEV strain, and the GDt29 attenuated vaccine showed higher protective efficacy against AEV than the commercial vaccine. Furthermore, contact-exposed chicks bred with GDt29-vaccinated birds generated high titers against AE virus (S/P > 2.8). Collectively, our studies are proof of the principle that GDt29 might be an ideal vaccine candidate to prevent AEV infection, and they highlight the utility of using a live vaccine against AEV.
This study was supported by National Key R&D Program of China (2017YFD0502001) and by Guangdong Province Science and Technology Plan Project (2015A020209137, 2016A050502042, 2016A020210125).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no competing interests.
All animal experiments were approved by the Committee of the Ethics on Animal Care and Experiments at South China Agricultural University (approval ID: 201004152). All study procedures and animal care activities were conducted in accordance with the national and institutional guidelines for the care and use of laboratory animals.
- 20.Taunde P, Timbe P, Lucas AF, Tchamo C, Chilundo A, Dos Anjos F, Costa R, Bila CG (2017) Serological evidence of avian encephalomyelitis virus and Pasteurella multocida infections in free-range indigenous chickens in Southern Mozambique. Trop Anim Health Prod 49(5):1047–1050CrossRefPubMedGoogle Scholar