الفهرس | Only 14 pages are availabe for public view |
Abstract Experiment was carried out to determine : The effect of addition of beta-glucan to Nile tilapia (Oreochromis niloticus) diet on growth and health and the effect of beta-glucan on immune response of nile tilapia challenged with Aeromonas hydrophila. from these studies we can conclude: Fish groups exposed to 0.5% betaglucan in diet and control groups showed similar survivability rate (96%). Fish exposed to 1% betaglucan in diet showed 82% survivability. Fish fed on diets contain either 0.5% or 1% betaglucan in diet showed significant increase in average body weight, average body gain, body gain percent. While the addition of Aeromonas hydrophila, showed significant decrease in all growth parameters. Healthy fish treated 0.5% and 1% betaglucan in diet showed no significant changes compared to control fish on ALT level showed a significant decrease, Creatinine level showed no significant changes, showed a non-significant increase on immunoglobulin (IgM) level, fish on Nitric oxide level showed no significant changes, showed a significant increase when compared to control fish on Lysozyme level and showed no significant changes when compared to control fish on Cortizol level while Infected fish, treated with betaglucan 0.5% and 1% when compared to infected, non-treated. The histopathological alterations were recognized in the organs of fish received feed contain different concentration of betaglucan and infected with Aeromonas hydrophila. A section in gills of Oreochromis niloticus infected with Aeromonas hydrophila stained with H&E showed congestion of gill lamellae. While section in gills of Oreochromis niloticus fed betaglucan 0.5% and 1% infected with Aeromonas hydrophila stained with H&E showed slight congestion of gill lamellae was the only histopathological change observed in gills and fusion of gill lamellae respectively. |