Ecology, Environment and Conservation Paper

STUDY OF OVARIAN MATURATION OF FRESHWATER FEMALE PRAWN, MACROBRACHIUM ROSENBERGII WITH REFERENCE TO HISTOLOGICAL AND VISUAL CHANGES

A.K. Sonawane, R.S. Kale and A.V. Bhamare

Abstract

According to the general appearance and macroscopic observations of ovary, oocyte diameter ad histology of ovarian tissues four different stages of ovarian development were found viz., Immature, Maturing, Mature and Spent. The distinction of different stages of the oocyte depends upon their cytoplasmic content, changes in the nucleus and size of the oocytes which can be classified as, Oogonia which are small spherical cell with round nuclei which lack stainable yolk material. The average cell diameter was (24.02 μ), nuclear diameter (17.4 μ) and cell volume (7416.955 μ). Pre-vitellogenic oocytes - These oocytes increase in volume and acquire a large amount of basophilic cytoplasm with devoid of yolk material. Oocytes measures (38.16 μ), (24.48) and (29080.61 μ) in cell diameter, nuclear diameter and cell volume respectively. Vitellogenic oocytes - The oocytes enter a synthetic phase resulting in the formation of yolk. The appearance of follicle cells is noticed in these oocytes. The nucleus, nucleolus, ooplasm and follicular cells undergo marked changes in their cytology viz., Vitellogenic-I oocytes which measured (60.24 μ), (11.28 μ) and (114401.9 μ) in cell diameter, nuclear diameter and cell volume respectively. Vitellogenic-II oocytes measures about (94.51 μ), (34.32 μ), (216482.13 μ) in cell diameter, nuclear diameter and cell volume respectively. Vitellogenic-III oocytes measures about (156.96 μ), (27.84 μ), (2023696.3 μ) in cell diameter, nuclear diameter and cell volume respectively. Whereas, degenerating oocytes are almost of the same size as tertiary vitellogenic oocytes and can be located by disintegration of the nucleus and appearance of vacuoles.