1Department of Fishery Pathology and Microbiology, West Bengal University of Animal and Fishery Sciences, Belgachia, Kolkata 700 037 (W.B.).
2Department of Animal Nutrition, WBUAFS, Kolkata (W.B.).
3Department of Zoology, University of Lucknow (U.P.).
*Corresponding Author.
The present study revealed the effect of oral administration of yeast cell wall (YCW) preparation from Saccharomyces cerevisiae on non-specific immune responses of goldfish, Carassius auratus. Fish were fed experimental diets for 15 days and then switched back to control diet (once a day) for 20 days. Non-specific immunity was assayed before and at the end of the experimental feeding period by determinng the superoxide anion production, phagocytosis, nitrite production and proliferation of leukocytes. The production and in vitro phagocytic activity of the leucocytes increased gradually and the increase was highly significant (P<0.01). Nitrite production was also found to be increased gradually, and was highly significant (P<0.01) on 0 day compared to control fish (before experiment). In vitro lymphocyte proliferation increased but the differences were observed to be insignificant between control and treated fish throughout the experimental period. The result showed that the supplementation of YCW preparation in feed for 15 days had a considerable immunostimulatory effect on goldfish and hence indicated the potentiality of YCW as an immunostimulant for goldfish.
