Studies On The Toxic Effects Of Aqueous Extract Of Sasanqua Cake On Monopterus Albus

The present paper was designed to determine the toxic effect of sasanqua cake on juvenile and adult rice field eel Monopterus albus. Blood physiological and biochemical parameters, immunological indices and genetic toxicity were determined and liver and kidney tissues microstructure were observed. The results were shown as followed:1. The acute toxicity test of sasanqua cake on juvenile rice field eel (initial mean weight: 0.28±0.15g, mean±S.D.) showed that the 50% lethal concentration (LC₅₀) of 96 hours was more than 25mg/L. When fed on, the remaining rice field eel after the acute toxicity test couldn't be infected with saprolegniferax and were able to normally survive but these in control group died. Based on the observation, sasanqua cake could be regarded as the low - grade toxicant to rice field eel juveniles, and the proper concentration of sasanqua cake could improve the fingerling's anti-diseases ability and survive.2. The acute toxicity test of sasanqua cake on adult rice field eel (initial mean weight: 38.66±12.19g, mean±S.D.) showed that the LC₅₀ of 72 hours and 96 hours were 37.20mg/L and 30.00mg/L respectively, and that the safe concentration was 3.00mg/L. There were no significant toxic effects of sasanqua cake on the blood RBC, Hb, Eof and Ht (P > 0.05), respectively. Similarly, sasanqua cake could be regarded as the low-grade toxicant to rice field eel adults and had no significant effects on the four blood physiological parameters with short -term trial.3. The results of the sub-acute toxicity test indicated that sasanqua cake had significant influences on the RBC and Eof but not on the Hb and average Hb of erythrocyte. But with the 15 - day trial, the RBC in treatment groups could return to the normal level, inferring that the toxic effects of sasanqua cake on rice field eel were mainly caused by the tea saponin.4. The results of sub-acute toxicity test showed that the sasanqua cake could increase the serum Glu, but the serum Glu didn't change with the concentration and the time, and the sasanqua cake had no significant effect on the important organs and ALP activity.5. The genetic toxic trial indicated that sasanqua cake had no genetic toxicity on rice field eel but could reduce the erythrocytes micro- nuclei rate.6. The sub-acute toxicity test suggested that sasanqua cake could improve the serum agglutinating titer and bacteriolytic activity, and accordingly increased immunity and anti-diseases ability. 7. The present trial indicated that sasanqua cake didn't markedly hurt the liver and kidney since there were no significant differences in microstructure of liver and kidney between the treatment groups and the control group.In conclusion, the toxicity of sasanqua cake could be attributable to the tea saponin. Sasanqua cake belonged to low-grade toxicant to juvenile and adult rice field eel. Within the range of sub-acute concentration, sasanqua cake significantly influenced RBC, Eof and Glu but not on other physiological and biochemical parameters, germ plasm, immunity, and microstructure of liver and kidney.