Modulation of the effectiveness of 17-alpha-hydroxy-20-beta-dihydroprogesterone or of a gonadotrophic extract on the in vitro intrafollicular maturation of oocytes of the rainbow trout Salmo gairdnerii by various non-maturing steroids [Translation from: Compte Rendu Hebdomadaire des Seances de l'Academie des Sciences, Paris, Series D 281, 811-814, 1975]

The effectiveness of 17 α-hydroxy-20 β-dihydroprogesterone (17 α-20 β Pg) or of a trout hypophyseal gonadotrophic extract on the in vitro intrafollicular maturation of trout oocytes can be modulated by steroids which do not have a direct maturing effect; the effectiveness of the gonadotrophic extract is lowered by oestradiol and oestrone and increased by testosterone. As these steroids have no significant effect on maturation induced by 17 α-20 β Pg, the site of their activity is probably in the follicular envelopes. Corticosteroids, and Cortisol and cortisone in particular increase the effectiveness of the gonadotrophic extract, but increase the effectiveness of 17 α-20 β Pg even more strongly, suggesting that this 'progestagen' has a direct effect on oocyte sensitivity.

In vitro phagocytic study of blood leucocytes and peritoneal macrophages of walking catfish Clarias batrachus ( Ham.) against Aeromonas hydrophila and Escherichia coli.

In observation of in vitro phagocytic activity against Aeromonas hydrophila isolate 34k (a virulent form) and Escherichia coli (an avirulent bacteria) of neutrophil- and monocyte-like cells of walking catfish Clarias batrachus showed phagocytosis. N eutrophils and monocytes phagocytized the avirulent form of bacterial isolate more than the virulent one. Other blood leucocytes did not show phagocytosis. Peritoneal macrophage of the fish were separated by glycogen elicitation and the macrophages were being adhered on plastic cover slips for studying their in vitro phagocytic activity. Most of the cells were alive after adherence and showed phagocytosis against the virulent and avirulent bacteria. The percent phagocytosis and phagocytic index were higher against the avirulent E. coli than the virulent A. hydrophila.