Efficiency of oral Aeromonas hydrophila vaccine and Tumeric powder mixture on immune response of Nile tilapia (Oreochromis niloticus)

The aim of the present study was to evaluate the dietary dosages of a mix from formalized killed vaccine and turmeric on enhancement the immune response and disease resistance against the pathogenic Aeromonas hydrophila  that cause mass mortality in Oreochromis niloticus. Four different dosages of turmeric 0, 1, 3 and 5% kg−1 feed were fed to the fish for 15 days at rate of 3% body weight then a dose of a mix of   Aeromonas hydrophila oral formalized vaccine wetpacked whole cell at level of 5 mg/g of diet and Tumeric mixed feed was giving as initial dose at the beginning of the experiment for one week followed by booster dose after 15 days. Blood was collected before and after vaccination; serum was separated for antibody titer assay, hematological parameters as (IGM, ALT and AST) were done. At the end of the experiment, fish was challenged with 0.2 ml Aeromonas hydrophila I/P per fish and the mortality (%) was recorded after ten days post challenge. The serum antibody titer were significantly (P<0.05) higher on 56 days of feeding of 1, 3 and 5 g of turmeric per kg of feed mixed with formalized killed vaccine wet-packed whole cell at level of 5 mg/g of diet. The survival rate was 0, 80, 95, 100 and 100% in challenge test groups T1, T2, T3, T4, and T5 respectively. IGM, ALT and AST were significantly (P<0.05) higher up to 56 days of feeding mainly T4. The result showed that turmeric at a dose of 3-5 mg / g−1 feed mixed with Aeromonas hydrophila oral formalized vaccine wet-packed whole cell at level of 5 mg/g of diet provided the greatest protection to pathogen challenge.