Distribution and Risk Factors Associated With Tilapia Parvovirus (TiPV) Presence in Red Hybrid Tilapia (<i>Oreochromis</i> spp.) Farms in Thailand.

Abstract

Emerging viral diseases, such as tilapia parvovirus (TiPV), are having a significant economic impact on global tilapia aquaculture. TiPV is responsible for the mass mortality of Nile tilapia (<i>Oreochromis niloticus</i>) and red hybrid tilapia (<i>Oreochromis</i> spp.) in China, India and Thailand. We, therefore, aimed to determine the current status of TiPV infection and distribution and the risk factors associated with TiPV infection in red hybrid tilapia farms in Thailand. In this cross-sectional study, a total of 101 samples, each comprising five moribund fish, were collected from 40 red hybrid tilapia farms across various provinces in Thailand between September 2022 and March 2024. The data on the farm characteristics and management practices were obtained via questionnaires and direct observation. A total of 23 factors were assessed, including six related to farm characteristics, 13 associated with farm management practices and four concerning the presence of other pathogens. The data from 101 samples were analysed using unconditional and mixed-effects logistic regression, revealing a percentage of TiPV infection was 11.88%. Two significant risk factors associated with TiPV infection were identified: the source of the fish (<i>p</i>=0.020) and the initial fish weight at the stocking date (<i>p</i>=0.026). Conversely, the feeding method (<i>p</i>=0.039) was found to be a protective factor against TiPV infection. This study is the first to investigate the epidemiology of TiPV infection in farmed red hybrid tilapia. Our findings are important for improving farm management practices, mitigating the risk of TiPV infection and developing effective disease control strategies.