الفهرس 
Review of literatureOnly 14 pages are availabe for public view
 |  | from | 195 |  |  |
| | | from | 195 | | |
Abstract
F o ot-and-mouth disease virus (FMDV) is the most economically important
veterinary pathogen due to its highly infectious nature, ability to cause persistent
infection and long term effects on the condition and productivity of the many animal
species. In August 2009, a foot-and-mouth disease outbreak has struck cattle and
buffaloes in different localities of Egypt exerting severe economic losses to livestock
industry. Fifteen representative specimens (tongue epithelium and foot vesicular fluid)
were collected from different governorates (Behairah, Menoufia and Kaferel-Sheikh).
Several assays of reverse transcription polymerase chain reaction (RT-PCR) using
universal primer sets corresponding to highly conserved regions of the 2B sequence
(P32&P33), followed by FMDV VP1-based RT-PCR using serotype specific primers;
(P33& P38) for serotype O and (A-1C562F, A1C612F and EUR-2B52R) for serotype
A. Utilizing a FMDV universal primer set, the FMDV could be identified as outbreak
causative agent in all 15 examined samples. The results of serotype-specific RT-PCR
assays on 15 samples revealed positive amplification for serotype O in all samples,
where as by using serotype A-specific primers (A-1C612F, EUR-2B52R and
A1C562F, EUR-2B52R). The results were 1/15 and 12/15 were positive, respectively.
The specific RT-PCR products were subjected to direct nucleotide sequencing, blast
searches, multiple alignments and phylogenetic analyses of VP1 nucleotide sequence
data demonstrated that outbreak FMDV is serotype O even the samples were gave
positive with serotype A-specific primers. The detected virus was closely related to
PanAsia strain in Middle East-South Asia (ME-SA) topotype. The present study
concluded that The RT-PCR technique using the described serotype O-specific
primers constitutes a simple, rapid and efficient method for the diagnosis and
characterization of FMDV in clinical samples if accompanied with the nucleotide
sequencing, but the serotype A-specific primers have to be evaluated in
comprehensive study. 1- In this study a total number of 15 field samples were collected
from cattle and buffaloes in different governorates in Egypt
suspected to be infected with foot-and-mouth disease virus.
2- Molecular characterization of collected samples was done using
RT-PCR for amplification of 2B gene for universal detection of
foot-and-mouth disease virus and VP1 gene for serotyping of the
detected virus.
3- Out of 15 samples, 15 samples were positive for amplification of
2B gene by using the universal primers (P33 and P32).
4- Out of 15 samples, 1 sample was positive for amplification of VP1
gene by using the serotype-specific primers for A serotype (A-
1C612F and Eur-2B52R).
5- Out of 15 samples, 12 samples were positive for amplification of
VP1 gene by using the serotype-specific primers for A serotype
(A-1C562F-Eur-2B52R).
6- Out of 15 samples, 15 samples were positive for amplification of
VP1 gene by using the serotype-specific primers for O serotype
(P33 and P38).
7- Out of 15 samples, 4 samples were subjected to sequence of full
length of VP1 by using sequencing primers (A-1C612F, NK72, and
A-1D523R).
8- The sequence data of four samples revealed that the detected virus
was serotype O even that detected by serotype A-specific primers.
9- The sequence data of four samples were analyzed using Bioedit
program and the aligned fragment (633bp) full length of VP1 were
utilized with different known global FMDV serotype O for
construction of Phylogenetic tree using MEGA program version 5. 10- The phylogenetic tree revealed that local FMDV detected in
examined samples were related to PanAsia strain within ME-SA
topotype. Also have a relation to O1-Manisa-Turky-69 strain but
there are multiple amino acid changes in the main antigenic site
(site No.1).
11- The present study demonstrated the occurrence of FMDV
serotype O PanAsia strain Egypt. This may due to movement of
animals between infected areas and Egypt. This explains the
occurrence of outbreaks in vaccinated animal.
12- The present study demonstrate a simple, fast, and accurate
method for diagnosis and serotyping of FMDV as well as the
sequencing of full length VP1 to compare between the detected
virus and the vaccinal strain to evaluate the vaccine used in field.