Foot and mouth disease is one of the most important contagious diseases of cloven-hoofed animals that may cause sever economic impacts. One of the important aspects of FMD is persistent infection that may occur after recovery from clinical form of disease or following exposure of vaccinated ruminants with live virus. In order to evaluate prevalence of persistent infection with FMD virus in buffalos, this study was conducted on 100 mature female buffalos slaughtered in Ahvaz abattoir in south-west of Iran. Samples were collected from pharyngeal secretions and dorsal soft palate tissue and tested by RT-PCR method. The results of this study showed 2 positive samples out of 100 collected samples which is the first report in Iran. Since buffalos are in close contact with other sensitive animals such as cattle and sheep, they may be a great hazardous to the spread disease in the region.

In order to utilize a reliable, fast and sensitive test for detection of Foot-and-Mouth disease virus (FMDV) in clinical samples, a Reverse - Transcriptase Polymerase Chain Reaction (RT -PCR) method was optimized. This RT-PCR can detect FMD viral RNA in samples regardless of their serotypes. Four vaccine viral strains of types A (two isolates), 0 and Asia 1 were tested and a 131 bp pcr product from 28 region of FMDV genome was amplified. Thirty-seven clinical samples were also tested. The specificity of results was confirmed by direct sequencing of PCR products. This rapid molecular diagnostic method, which is sensitive and specific, can detect FMDV in clinical samples in less than eight hours. Therefore, it would be valuable for early detection of suspected FMDV outbreaks.

Objective: To determine frequency of FMDV carriers in slaughtered cattle at Zyaran abattoir.Project: Cross- sectional study.Samples: Three hundred and one tonsils of clinically normal cattle.Procedure: All of tonsils were tested for determination of FMDV genome using RT-PCR. Then, 30 samples were cultured on MDBK. 20 samples had positive finding in RTPCR test.Statistical analysis: Based on sex, age and breed of cattle, RT-PCR results compared with Chi-square and Fischer's Exact Test. McNemar test was used for comparing of virus culture results with RT-PCR.Results: Ninty nine samples were positive in RT-PCR. Relative frequency of FMDV genome presence in tonsils of clinically normal cattle had a significant difference based on sex and breed. The Sistani and Holstein bred had the highest and the lowest relative frequency, respectively. Two positive samples on cell culture were serotype O of FMDV. One positive sample (Asia1) was shown by ELISA.Conclusion: Total relative frequency of positive FMDV genome (32.9%) indicates the extensive exposure to FMDV. Breed variation among Sistani cattle (as a variety of Bos indicus) and other bred shoud be studied in a controlled condition.

Foot and Mouth Disease (FMD) vaccine is one of the inactivated vaccines and its potency depends on the antigen quality, antigen concentration per dose, and adjuvant. In this study to introduce the better antigen concentration method, both active and inactive of three serotypes O, A05, and Asia of FMD virus were used. Each of the virus type was cultivated in BHK21 cell culture and half of each viral suspension inactivated by ethylene imine. The physical method; ultra filtration (cross flow system) and the chemical method; treatment with poly ethylen glycole (PEG6000) were used for virus concentration following safety assay. The quantity of virus recovery was evaluated by virus adsorption by aluminum hydroxide gel, complement fixation, ELISA, TCID50 titration, and sucrose concentration on the collected samples. The results indicate that the concentration rate did not affect virus adoption by aluminum hydroxide gel and the quantity of virus recovery using ultra filtration was higher than PEG precipitation.

Foot and mouth disease (FMD) is a severe, highly contagious viral disease of cloven-hoofed ruminants caused by an aphthovirus of the family Picornaviridae. The disease in cattle is clinically characterized by fever and vesicles on the foot, in the oral cavity and on the mammary gland. This study was carried out to determine the changes in some serum biochemical parameters of cattle naturally infected with FMD O in Shahrekord district, Iran. For this purpose, blood samples were obtained from 23 Holsteins with clinical signs of FMD, as well as 22 blood samples from healthy animals. Serum analysis revealed significantly higher levels of AST, CK, CK-MB and LDH activities as well as MDA, troponin I, glucose and triglycerides concentrations in FMD-affected cattle compared to healthy control group (p < 0. 05). Serum GPx and SOD activities in cattle with FMD were significantly lower than those in normal animals (p < 0. 05), while there was no significant difference in serum CAT activity between 2 groups of animals. It is concluded that oxidative stress and some degrees of myocardial and pancreatic lesions develop in FMD-affected cattle. These findings provided information to better understand the pathogenesis of the disease and gives further insight to improve supportive treatment procedures in FMD virus infection in cattle.