Host: The Japanese Society of Toxicology
Antibiotics are widely used in veterinary drugs and feeding additives, which causing the accumulation of antibiotics in animals, and excreted in the urine and feces at high concentrations in a biologically active form, and causing environmental pollution. In this study, zebrafish were used as an animal model to research the reproductive toxicity of tetracycline hydrochloride (TCH) at environmental concentrations. Four-month-old parental zebrafish (F0) were exposed to TCH (0.1 μg·L-1, 1 μg·L-1, and 100 μg·L-1) for 30 d and then mated to obtain F1 generation zebrafish. The results showed that low-dose TCH exposure caused a significant reduction in zebrafish spawning and a significant decrease in the overall quality of embryos (p < 0.05). TCH also delayed the development of ovaries and testes in the F0 generation and inhibited the maturation of follicles (p<0.05). TCH significantly inhibits the expression of reproduction-associated genes (eg. cyp19a, vtg1, and vasa mRNA) in a dose-dependent manner (p<0.05). Morphological changes such as pericardial edema and curvature of the spinal cord were observed in the F1 offspring. Further detection of genes related to bone development revealed that TCH inhibited the expression of runx1, sox9a, sox10, and col2α1a mRNA in juvenile fish. The above findings indicated that low-dose of TCH affects the reproductive function and embryonic development of zebrafish.
Keywords: Tetracycline hydrochloride; Zebrafish; Reproductive toxicity; Embryonic development
