Comparative Analysis of Immune Function of Three Wild Mandarin Fish Populations in Yuanjiang River Basin

Abstract

Mandarin fish Siniperca chuatsi (Basilewsky) is a unique species in East Asia and has very important ecological and economic value. There are significant differences in immune function between different populations of Mandarin fish. However, up to now, the comparative study of immune indices of different populations of wild mandarin fish has been scarce. In the present study, the transcription level of Immunoglobulin M (IgM) and blood serum immunologically related enzyme activity of three wild Mandarin fish populations from Wuqiangxi reservoir, Lingjintan reservoir, and Taoyuan reservoir of Yuanjiang river basin were detected. In head kidney, spleen and in the liver of Mandarin fish, the transcription level of IgM was highest in Taoyuan reservoir followed by Lingjintan reservoir, and was lowest in Wuqiangxi reservoir. The catalase activity of Mandarin fish was highest in Taoyuan reservoir followed by Wuqiangxi reservoir, and was lowest in Lingjintan reservoir. Total number of white blood cells, lysozyme activity, acid phosphatase activity, superoxide dismutase (SOD) activity, and alkaline phosphatase activity of Mandarin fish were in line with immunoglobulin M gene expression, which were highest in Taoyuan reservoir followed by Lingjintan reservoir, and lowest in Wuqiangxi reservoir. This indicated that the immune function of Mandarin fish from Taoyuan reservoir was strongest, and these fish had the greatest resistance to harmful invaders such as parasite, bacteria, and virus compared to Lingjintan reservoir group and Wuqiangxi reservoir group. The results of this study provide a theoretical basis for disease-resistant breeding and germplasm optimization in mandarin fish breeding production, and may be valuable in future research