ISSN: 2577-4050
Authors: Sudha Devi AR*, Aswani A and Bhadravathi Kenchappa CS
This study elucidated the light and electron microscopic observations on mandibular organ in relation to the female reproductive cycle of the edible freshwater crab Travancoriana schirnerae. Results indicated that the gland underwent correlative changes in accordance with the phases of reproduction, with highest activity during the reproductive phase and least during the pre and post-reproductive phases. During the reproductive phase, the gland cells and their nuclei exhibited hypertrophy and the cytoplasm displayed numerous extraordinarily hypertrophied, unusually dense, polymorphic mitochondria with increased number of transverse tubular cristae, prominence of Golgi with swollen cisternae, vesicles and dense granules, swollen tubular cisternae and vesicles of rough and smooth endoplasmic reticulum, rich free ribosomes and electron dense secretory granules, characteristic of high cellular activity in connection with the synthesis of methyl farnesoate, the secretory product of the mandibular organ. The abundance of hemocytes, in particular, granular hemocytes enclosing electron dense granules of varying sizes, shapes and density in the wide hemolymph channels and sinuses during the reproductive phase suggested their role in the storage and transport of the secretory product of the gland.
Keywords: Freshwater Crab; Mandibular Organ; Reproductive Cycle; Travancoriana schirnerae; Ultrastructure
