Abstract:The present study aimed to evaluate the effect of Astragalus polysacharide (APS) and Angelica sinensis polysaccharide (ASP) on the cell apoptosis of Carassius auratus induced by Aeromonas veronii. Negative control group, positive control group, APS group and APS group (four groups) were set up in this experiment. Experimental fish was infected with A. veronii. The changes of apoptosis rate and cell cycle in blood cells were determined by flow cytometer. The morphology of apoptosis cells were observed by fluorescence microscopy and transmission electron microscopy (TEM). The results showed that the blood cell apoptosis rate of the positive control group was significantly higher than those of two polysaccharide groups and negative control group after being infected with A. veronii. Polysaccharide groups could significantly reduce the apoptosis rate and APS group had more significant effect than ASP group. Karyopyknosis appeared in the liver cells and the head kidney lymphocytes of crucian carp. Besides,chromatic agglutination adjacent to the nuclear membrane and apoptotic bodies appeared after the infection. Compared with the negative control group, the A. veronii infection could significantly decrease the percentage of S/G2+M phase cells and increase sub-G1 phase cells in crucian carp blood cell cycle and the infection had an effect on inhibiting cell division and inducing apoptosis. Compared with the negative control group, the proportion of G0/G1 and sub-G1 cells in the polysaccharide group was significantly reduced, and the proportion of S/G2+M phase cells was significantly increased, which indicated that polysaccharide groups can promote cell division and inhibition of apoptosis. Based on the above results, we found that APS and ASP could effectively inhibit crucian carp apoptosis induced by A. veronii when the addition was 1%.