• S S Khanna

      Articles written in Proceedings – Animal Sciences

    • Relative fecundity ofLabeo gonius (Ham.) from Nanaksagar reservoir

      S N Joshi S S Khanna

      More Details Abstract Fulltext PDF

      Eighty three specimens ofLabeo gonius were examined to study the fecundity of the species. The weight of the two ovaries together accounted for 14·71 to 21·87% of the total weight of the fish. Specimens about 1 kg in weight had ovaries weighing about 205·312 g on an average and this worked out to about 19·93% of the total weight of the fish. The average number of eggs per g weight of fish and ovary was 271 and 1424 respectively. The fecundity per kg body weight of fish was 286111. The relationships between standard length and fecundity, total weight and fecundity, ovary weight and fecundity, ovary length and fecundity, ovary volume and fecundity, fish length and ovary weight and fish weight and ovary weight ofLabeo gonius have been determined.

    • Structure and seasonal changes in the testes of a freshwater crab,Potamon koolooense (Rathbun)

      P C Joshi S S Khanna

      More Details Abstract Fulltext PDF

      The paired ‘H’-shaped testes ofPotamon koolooense show histomorphological changes during various stages of maturity. Seminiferous tubules show different stages of spermatogenesis. A few undifferentiated or resting spermatogonia supply a new crop of germ cells for the next breeding season. In a tubule the meiotic divisions occur more or less synchronously in all the primary or secondary spermatocytes. Sperm consists of a head and mitochondrial vesicle which encloses axial filament and distal centrosome. Spermatogenesis activity is seasonal. Spermatogenesis begins in January-February, progresses slowly through March, reaching its peak in April-May. However, all the tubules do not mature simultaneously. Spermiation occurs during May and June, the spermatogenesis ceases gradually, and by December the testes enter a brief period of rest.

    • Seasonal changes in the ovary of a freshwater crab,Potamon koolooense (Rathbun)

      P C Joshi S S Khanna

      More Details Abstract Fulltext PDF

      The ovaries ofP. koolooense which are paired H-shaped structures undergo seasonal morphometric and histological changes. A minute oviduct leads into the seminal receptacle which receives sperms during breeding season. Oogonia and young oocytes develop in the germinal zone, present in the centre of the ovary. The resting or residual oogonia which occur throughout the year divide shortly after ovulation and supply new crop of germ cells for the next breeding season. Five maturational stages of ova have been described on the basis of changes that occur in their nuclei and cytoplasm. They are oogonium, premeiotic oocyte, previtellogenic oocyte, vitellogenic oocyte and the ripe ovum. Spawning occurs during May or June. The weight of the ovaries, gonad index and ova diameter were minimum in June and reached a maximum value in April.

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