Morphometric and histological studies of the gonads of male and female hatchlings of olive ridley turtles (Lepidochelys olivacea)

Sex determination in the neonatal phase is difficult because gonadal dimorphism is found in turtle hatchlings. This study aimed to confirm gonad dimorphism in olive ridley turtles (Lepidochelys olivacea) using morphometric and histological studies. Samples were collected from Boom Beach, Banyuwangi in turtle nests based on the number of nests, densities and habits. The dead turtle hatchlings were collected and dissected for gonad determination. We observed the morphometry of the gonad shape and size. We used H&E staining for both sexes to determine differences in the histological structure of the gonads. All data are expressed in means +/- SD then analyzed using two-sample t-test (p<0.05) for significant statistical analysis. The gonads were found in the dorsal part of the body cavity, posterior to the lungs, the ventral base of the kidneys, and the walls of the peritoneum. Gonadal cortex thickness, lumen diameter of the paramesonephric duct and germinal epithelium were significantly greater in females than males. In conclusion, there were significant differences in gonads morphometry. We revealed that the structure of the gonadal cortex, the diameter of the lumen of the paramesonephric duct and the germinal epithelium can determine the sex of olive ridley turtle hatchlings.