4. Discussion
In the recent years, the herbal immunostimulants have emerged as an
effective alternative strategy in lieu of antibiotics and chemotherapies in
fish disease management.
In fish administration of a number of herbal immunostimulants through oral (feed) or injection have demonstrated their potential to improve
growth performance, disease resistance and the immune system. The mangrove trees are widely distributed in coastal area in tropical
and temperate zones, but there is little or no report on the effect of
mangrove species on immune system of fish. Therefore, the present
study investigated for the first time the effect of dietary administration
of R. apiculata extract in A. sebae against V. alginolyticus.
The present study has demonstrated that feeding infected A. sebae at
1%, 5%, and 10%with R. apiculata extract enriched diets result in a slightly
lower SGR when compared to control; however the FCR increased
slightly during the course of the experiment. The results agreewith previous
studies in the infected grouper. Olive flounder and Parrot fish
which had a significantly enhanced the SGR and FCR after herbal treatment.