Epidemiological characteristics and risk factors for Newcastle disease in chickens in three districts of Tien Giang province

Abstract

The objective of this study aimed at investigating some epidemiological characteristics and risk factors relating to Newcastle disease (ND) in the chicken flocks raising in three districts (Cho Gao, Go Cong, Cai Be), Tien Giang province from Jan., 2018 to Apr., 2019. The data of 140 chicken farms relating to farm management practices, ND experience and vaccination were collected from the household farms using the predesigned questionnaires. A total of 140 spleen samples from 40 chicken flocks were collected to detect the Newcastle disease virus using Realtime RT-PCR technique at the laboratory of the Regional Animal Health Office No.6. The studied results showed that the ND prevalence in the chicken flocks was 46.67%, which was mostly detected in the chickens at 4 to 16 weeks old and ND vaccination for the chicken flocks was not adequate. In the chicken flocks having positive samples with ND, there were several chickens showing the typically clinical symptoms and signs of Newcastle disease, such as: dyspnea, watery blue feces, eyelids edema, hemorrhagic signs in trachea, proventriculus and cloaca. The main risk factors for Newcastle disease in the chicken flocks were determined, including the farm owners were not do disinfection periodically (2 times per week) for the farms, ND vaccination for the chicken flocks was not adequate, the wild birds appeared in the farm areas, the abnormal fluctuations of bird in the farms, particularly there were many mites found in the chickens