Preliminary Histological Investigation of East Asian Bullfrog (Hoplobatrachus rugulosus) Tadpoles Exposed to Potassium Chlorate

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Wararut Buncharoen
Monruedee Chaiyapo
Supap Saenphet
Athibeth Buajai
Phornphan Phrompanya
Kanokporn Saenphet


Potassium chlorate has been used widely in northern Thailand to induce off-season flowering of longan trees. Therefore, it is highly possible that potassium chlorate could contaminate the surrounding waters. Although adverse effects of agrochemicals on the aquatic vertebrates are well documented, the exploration of histopathological changes under potassium chlorate toxic effects on amphibians is limited. The present study aimed to histopathologically investigate the effect of potassium chlorate on the kidney, liver, and gonad of east Asian bullfrog Hoplobatrachus rugulosus larvae. The 3-day-old tadpoles were divided into 0.1, 0.5, 1.0, and 1.5 ppm exposure groups to potassium chlorate for 24 weeks. Larval samplings were conducted for histopathological examination in pro- and complete- metamorphic stages. The histopathological changes of all investigated organs were observed in potassium chlorate treated groups, especially at the high concentrations (1.0 and 1.5 ppm). Kidney tissues showed glomerular shrinkage together with congestion, while vacuolization and degeneration of hepatocytes, expanded sinusoidal spaces, and leukocyte infiltration were found in the liver. Moreover, atretic oocytes and karyorrhexis were recognized in the ovary. Our results suggested that the use of potassium chlorate at high concentrations adversely affected vital organs of H. rugulosus tadpoles and might lead to the decline of the amphibian population.

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How to Cite
Buncharoen, W.; Chaiyapo, M.; Saenphet, S. .; Buajai, A.; Phrompanya, P.; Saenphet, K. Preliminary Histological Investigation of East Asian Bullfrog (Hoplobatrachus Rugulosus) Tadpoles Exposed to Potassium Chlorate. Microsc. Microanal. Res. 2022, 35, 38-45.
Original Articles


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