Abstract:

In order to make early warning and forecast of Pelteobagrus fulvidraco disease, and reduce the risk of fish disease outbreak, the characteristics of weather changes before and during the occurrence of Pelteobagrus fulvidraco disease were analyzed based on the investigation of the diseases of Pelteobagrus fulvidraco in spring in 2020 and 2021. The fish disease incidence grade standard and the mathematical method of climate stress index (CSI) of fish diseases were put forward, and the relationship between them was analyzed by statistical method. The index of disease prediction of climate stress was established by using rank sum test and percentile threshold method. The results showed that the rapid change of weather, such as sharp cooling and precipitation in spring, could result in low temperature and less oxygen environment of fish pond water, which was the catalyst of P. fulvidraco disease outbreak. There was a significant correlation between the disease grade (DG) and CSI ( D G = 0 . 215 · e^{0.0251\times CSI}, P<0.001). According to the analysis, the corresponding CSI of mild, moderate and severe ulcerative syndrome occurrence were 60, 80 and 100, respectively. The conclusion could provide a basis for the weather forecast of Pelteobagrus fulvidraco disease in spring.

Key words: Pelteobagrus fulvidraco, ulcerative disease syndrome, climate stress index, prediction