Abstract

HISTOPATHOLOGICAL ALTERATIONS IN THE OVARY OF FRESH WATER GOBIID FISH GLOSSOGOBIUS GIURIS UNDER PESTICIDAL STRESS

Narayanaswamy. S.Y*

ABSTRACT

Histological changes in the Ovary of fish Glossogobius giuris was observed during spawning phase, on the treatment with sublethal concentrations of Malathion (0.05, 0.25 and 0.5 ppm) for 24, 48, 72 and 96 hrs intervals, histology represents a useful tool to assess the degree of pollution, particularly for sub-lethal and chronic effects. In this paper, propose a standardized tool for the assessment of histological findings which can be applied to ovary. The results of the present study showed morphological changes in the cell structure. Investigation on Ovary cells showed degranulation and hypertrophy of cells and nuclei, after the fishes were exposed to Malathion treatment, these changes further intensified with 0.25 ppm treatment through the appearance of extensive intercellular spaces. In higher concentration of Malathion treatment reduces in the number and diameter of the Ovary cells, which indicates possible reduction in the synthesis of hormones. The large oocytes (diameter: 198.48 ± 0.01μ) with large well defined nuclei and distinct nucleoli. The tunica albuginea is made up of muscular and connective tissue fibers and contains blood capillaries The ooplasm was disorganized and the zone pellucida had swollen, the treatment with 0.25 ppm of malathion for 72 hrs, showed that inhibition of oocyte development. The breakdown of germimalvesicles were observed. The yolk granules were disappeared. The size of the ovary reduced On treatment with 0.05 ppm of malathion for 96 hrs, the ooplasm was disorganized and the zona pellucida had swollen and defected from the original position. The percentage of oocytes stage VI decreased when compared to control (control: 10.83%, treated: 7.81%). The ovarian growth was inhibited with 0.25 ppm of malathion for 96 hrs, the oocytes and interstitial tissue were encapsulated by a connective tissue capsule consisting of germinal epithelium and tunica albuginea with blood vessels.

Keywords: Malathion, G. giuris, Ovary, Tunica albuginea and Zona pellucida.