Histopathological effects of carbaryl on testes of snake-eyed lizard, Ophisops elegans

Abstract

Due to their ecological niche and insectivore nature, lizards are of increased risk of exposure to pesticides in agricultural areas. In addition to their potential direct effects on non-target species, insecticides can also result in indirect impacts on lizard population by reducing their food source. Carbaryl is a common insecticide that is widely used in areas of Turkey that are home to a variety of reptiles. However, to date, little is known about the potential effects of the exposure of reptiles such as lizards or snakes to this pesticide. The aim of the study was to investigate toxic effects of carbaryl on the testes of snake-eyed lizard, Ophisops elegans that is common to regions in Turkey where Carbaryl is applied and that it can be easily cultured in the laboratory. Adult male lizards were exposed to carbaryl once by oral gavage in concentrations of 2.5, 25 and 250 μg/g. After 96 h, lizards were euthanized and dissected. Histopathological changes were detected by randomly counting 100 tubules in each lizard. Seminiferous tubules were categorized as normal, sloughing and disorganized tubules. Diameters of tubules were also measured. The differences in histopathological changes and tubule diameters were compared for statistical significance by one-way ANOVA, using SPSS 16.0. Histopathological changes were more prominent in medium- (25 μg/g) and high-dose (250 μg/g) groups than in the low-dose (2.5 μg/g) group. In the medium-dose group, the hexagonal appearance of most tubules disappeared, and they took on an oval shape. Sloughing was the characteristic tubule appearance of the medium group. In the high-dose group, significant increases in the number of disorganized tubules and prominence of haemorrhages was observed. Carbaryl caused histopathological defects on the testes of O. elegans, so it is clear that carbaryl affects male fertility in O. elegans.