THE USE OF THYME; Thymus vulgaris EXTRACT TO DEVELOP INACTIVATED VACCINES AGAINST PATHOGENIC
Pseudomonas Putida OF CULTURED RED TILAPIA;
(Oreochromis niloticus x O. mossambicus)
Abdelhadi Y.M.1; Hala F. Ayoub1; Mohamed M. El Tantawy 1;
NatrahFatin M.I.2 and Ina Salwany M.Y.2
1The Central Laboratory for Aquaculture Research (CLAR), Agricultural Research Center (ARC), Egypt.
2Department of Aquaculture, Faculty of Agriculture, University of Putra Malaysia (UPM) 43400, Serdang, Selangor, Darul-Ehsan (D.E.), Malaysia.
Corresponding Author: 00201211279416, [email protected]
This study aimed to investigate antibody titers and relative percent survival (RPS) of red tilapia vaccinated with Biofilm-coated vaccine (BFV) of P. putida with and without thyme extract. For this experiment, 375 red tilapia (25 fish/tank) have been used in 5 treatments including BFV of P. putida with 40 and 100 mg per ml thyme extract, BFV of P. Putida alone, thyme extract alone and control. The fish were kept in glass tanks for 12 weeks. Two booster doses of vaccines and other treatments were given at weeks 4 and 8 respectively after the initial dose. Blood samples were taken at zero day to get the pre-immune serum and every two weeks from the initial dose for antibody titration in the fish sera, using ELISA. Experimental challenge with virulent strains of Pseudomonas putida, P. fluorescens and P. aeruginosa has been done to test the vaccines efficacy and level of protection. Daily mortality was recorded for 14 days to estimate the cumulative mortality and relative percent survival (RPS) of the fish in different treatments. Results revealed that antibody titers and RPS in BFV of P. putida vaccine alone and BFV with 100 mg-ml gave the highest IgM titers and RPS.
Keywords: Pseudomonas putida, Biofilm-coated vaccine, Thymus vulgaris, thyme extract