الفهرس | Only 14 pages are availabe for public view |
Abstract In this study 852 serum sample were collected randlomy from apparently healthy sheep in Al-Giza, Al-Ismailia, Al-Behira and Al-Menya governorates. The serum were submitted for detection of antibodies against FMDV serotypes O1& A using SNT and ELISA. Differentition between vaccinated and previously infected sheep was done by PrioCHECK NSP blocking ELISA. The results indicatd that, antibodies aginst both serotypes of FMDV O1&A were detected from the four governorates under investigation. In Al-Menya governorate the percentage of O1 antibodies was 19.54% (34/174), while antibody percentage against A was 14.94 % (26/174). At the same governorate, the previously infected sheep (according to serum collected sample) were about 18.4% (32/174), when PrioCheck blocking ELISA used. In Al-Ismailia governorate the percentage against O1 was 18.4 (51/276) while for A, it was 24.6 (68/276), mean while sheep previously infected with FMDV were 17.4 % (48/276). In Al-Giza governorate 34.58% (46/133) of samples were positive to O1 while 18.04 %( 24/133) were positive to A, 29.32% of the collected serum samples showed previous infection with FMDV. FMDV serotype O1 antibodies percentage was 10.78% (29/269) in Al- Behira, while it was 25.65% (69/269) for A. 18.2% (49/269) was due to previous infection with the virus. Moreover, the effect of repeated vaccination on sheep with bivalent FMD vaccine locally produced was studied. The study showed that the non-strucural protein antibodies of FMDV started to appear since the 4th vaccination. The PrioCHECK FMDV NSP blocking ELISA was used in this study. On the other hand, virological investigation was done on samples collected from Al-Ismailia and Al-Behira governorates where FMD outbreaks were existed. The samples were tongue epithelium (E.T) and oesphaigael pharyngeal fluid (OP), Al-Ismailia (3 E.T and 7 OP) and Al-Behira (2 E.T and 11 OP). 99 The samples were inoculated in tissue culture BHK21 clone 13 cell line and in unweaned baby mice. Cytopathic effect (CPE) and classical clinical signs and deaths were observed. ELISA indicated that 2 E.T samples were of serotype O1 and 1 E.T of serotype A while 5 of OP samples were FMDV serotype O1 and 2 of serotype A in Ismilia governorate. In Al-Behira governorate 2 E.T samples of serotype O1 while 7 OP samples were of serotype O1 and 4 OP samples were of serotype A. The virological obtained results were confiremd by RT-PCR. E.T & OP isolated FMDV serotype O1 were used for extraction of FMDV RNA and subsequent amplification of 3D coding sequences, primers used in one step. RT-PCR achived success when the target FMDV 3D sequences (422 bp) were amplified. All the tested samples showed positive with variable visible intensity on ethidium bromide stained gel. Our results concluded that: FMD is still widely spread in Egypt, with higher rate in Upper Egypt than that of Lower Egypt. Egyptain sheep are playing an important role in epidemiology of FMD and issue of sheep vaccination is very important. FMD PrioCHECK test is useful in detection of previously infected animals and realability of the test in differentiation between infected and vaccinated animals. The results of PCR assay documented the occuracy and efficacy of the test rather than that of traditional one ( SNT and ELISA) . |