Precision Dosing in Zebrafish: An Anesthesia-Free Oral Gavage for Reproductive Toxicity Assessment in Zebrafish.

Oral gavage is ideal for studies requiring controlled dose delivery and timing, such as repeated dosing and longitudinal analysis, as shown in this study. An anesthesia-free gavage technique was used to administer daily estradiol doses to adult zebrafish for 40 days to evaluate reproductive toxicity (developmental and reproductive toxicity one stage). Results showed that neither estradiol administration nor the gavage method caused stress or injury, but both impacted reproductive capacity in a dose-dependent manner. Females exposed to the drug exhibited a reduction in gonadosomatic index (GSI) and changes in follicle maturation, while in males, only the number of cells in the testis was reduced. The authors have no interests to disclose.