الفهرس 
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Abstract
Foot and Mouth disease is considered as an acute febrile highly contagious viral disease affecting almost exclusively cloven-footed animals characterized by formation of vesicles and ulcers on tongue, feet, and mucous membrane of the mouth, checks, dental pads, gums, and the skin of the interdigital spaces. The disease also causes high losses in milk and meat production. In Egypt, FMD assumes an enzootic form and attacks susceptible animals, so routine prophylactic vaccination has been conducted with a locally produced serotypes O and A bivalent vaccine. Adjuvant considered one of the important factors in vaccine formulation, so evaluation of FMD vaccine production with two ready to formulate oil adjuvants Montanide ISA 206 and Montanide ISA 50 in comparison to conventional produced aluminum hydroxide gel-saponin vaccine. Three experimental batches of FMD vaccine were prepared. The virus was inactivated by binary ethylenemine and adjuvanted with Aluminum hydroxide gel-saponin, Montanide ISA 206 and Montanide ISA 50. Prepared vaccines was proven sterile and free from bacterial or fungal contamination, also FMD lesions did not appear on susceptible calve when inoculated in different sits of the tongue indicating that there are no viable viral residues after the inactivation process.
The results of potency testing of the three prepared vaccines in vaccinated calves showed the following results:
1- Humeral immune response of calves vaccinated with aluminum hydroxide gel-saponin vaccine revealed that serum antibody protective titer evaluated by mean of SNT and ELISA started at 3rd week post vaccination for both types, reached its highest titer at 8th, 10th week post vaccination for type O, A respectively and continued with the protective titer till the 16th week post vaccination and then started to decline under the protective level for both FMD virus types.
2- Mean protective serum antibody titers against FMD in calves vaccinated with double oil emulsion (Montanide ISA 206) evaluated by ELISA and SNT was started at 3rd week post vaccination reached the higher antibody level at 10th week and continued with the protective level till the 32nd week post vaccination, and then started to decline under the protective level for both FMD virus types O and A.
3- Humeral immune response of calves vaccinated with Montanide ISA 50 showed that mean protective serum antibody level evaluated by SNT and ELISA started at 2nd week post vaccination for both FMD types O and A. The highest level of antibody titer was at 16th week post vaccination for SNT for both. The highest level of antibody titer evaluated by ELISA was at 16th,14th week post vaccination for type O, A respectively. While the immunity duration lasted for 40 week post vaccination for both FMD virus types.
4- The results of potency testing of the three prepared vaccines in calves vaccinated then challenged with FMD virus strain O1/3/93-Egypt at 21 days post vaccination. The mean SNT antibody titer was in the protective level of the vaccinated calves prechallenge and showed 100% protection of vacci nated animals postchallenge. The control non vaccinated calves showed a clinical signs of FMD virus infection after challenged with 104 MLD50 virulent FMD virus, while the observation of the vaccinated animals with FMD vaccines revealed no clinical signs of FMD appeared on the challenged animals.
5- Montanide ISA 50 and Montanide ISA 206 offered long lasting immunity than aluminum hydroxide gel-saponin as adjuvant for FMD vaccine for more improvement of immunity, so, this study present a new concept could become a tool in the programs for the control of FMD in Egypt using members from Montanide oil adjuvtants series which had a clear impact on improvement of FMD vaccine potency.