• S D Rita Kumari

      Articles written in Proceedings – Animal Sciences

    • Maturation and spawning in the hill-stream loachNoemacheilus triangularis Day

      S D Rita Kumari N Balakrishnan Nair

      More Details Abstract Fulltext PDF

      Five stages of maturity have been delineated forNoemacheilus triangularis Day. Progression of the mode in each stage of maturity has been traced from ova|diameter studies. The size at first maturity for male is around 44·5 mm and for female around 52 mm. Spawning is asynchronous and prolonged. There may be successive spawning during the year. Sexes are present in almost equal numbers. Fecundity is dependent on length and weight of fish and on length and weight of ovary.

    • Oogenesis in a tropical loachLepidocephalus thermalis (Cuv. & Val.)

      S D Rita Kumari N Balakrishnan Nair

      More Details Abstract Fulltext PDF

      The development of oocytes has been traced in detail in the loachLepidocephalus thermalis. The various stages of oocytes are described under distinctive stages namely 1. chromatin nucleolus stage; 2. perinucleolus stage; 3. yolk vesicle stage; 4. primary yolk stage; 5. secondary yolk stage; 6. tertiary yolk stage; 7. migratory nucleus stage; 8. pre-ripening stage; 9. ripe egg stage. The yolk deposition is initiated as minute globules in the extravesicular ooplasm. A yolk nuclous is entirely wanting in any stage of oocyte maturation. The origin of new crops of oocytes and the formation of the micropyle are described. Nature of degeneration of unextruded ripe oocytes has been followed.

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