[Evaluate the frequency of foot and mouth disease viral carriers in slaughtered sheep in Mashhad industrial abattoir using RT-PCR]

Background: Foot -and- mouth disease [FMD] is endemic in Iran. Molecular techniques for diagnosis of persistent infection or carrier animals have shown a potential ability to improve the detection of a low genome copy number in samples

Objectives:The purpose of this study is to evaluate the frequency of foot and mouth disease viral carriers in slaughtered sheep in Mashhad industrial abattoir using RT-PCR

Methods: Samples were isolated from tonsil of 94 slaughtered sheep analyzed by RT-PCR experiment for the detection of FMD, identification of FMD virus serotypes and at the end nucleic acid sequencing were performed

Results: The results showed that the 23 samples [24/5 percent] were positive for the presence of FMD virus RNA, of which 89.9% of cases are type O and 3 cases of FMD samples did not respond. The results of the 1D genome sequencing of the nucleic acid virus showed that FMD virus of sheep [O/IRN/100/2010Sheep], has 92/02% similarity with the virus [O/IRN/67/2001-2005] and 88/42% similarity with the virus [O/IRN/15/2004-2008]

Conclusions: This study showed that the percentage of FMDV sheep carriers in Mashhad slaughterhouse was remarkable. Estimation of the frequency of carrier state in cattle and small ruminants is recommended as a monitor of control plan in the region

[Phylogenetic analysis comparing partial S1 gene of avian infectious bronchitis virus to commercial vaccine strains in Iran]

Background:Infectious bronchitis is a highly contagious disease which may cause poor weight gain and low feed efficiency in infected chickens. There are a large number of reported serotypes/genotypes, which makes the control of the disease more difficult through vaccination. However, there are only a few amino acid differences in the S1 protein of vaccine and wild type strains which are responsible for protection

Objectives: The purpose of this study is to compare IBV variants isolated from commercial chicken flocks in Iran with currently used vaccine strains

Methods: The partial S1 gene of the spike protein, covering a hypervariable and constant regions, was amplified and sequenced using conventional RTPCR

Results: Phylogenetic analysis of amino acid sequences revealed that eight of total nine isolates were divergence at least 21.8% from vaccinal Massachusetts serotypes, and six of nine isolates were divergence at least 22.7% from 4/91, and none of the nine isolates were similar to Dutch-type, D274,vaccine serotypes

Conclusions: These findings are essential for continuous surveillance disease control strategies and monitoring of variants, and thus emphasize on the importance of improving the vaccination program in Iran

Protective effect of Johne's disease attenuated vaccine in an intensive non-tuberculosis free dairy

This study was carried out to control Johne's disease [JD] without interfering with tuberculosis [TB] control programme. A dairy herd [n>1500 heads] was used over a period of 6 years, from 1994 to 1999 for this investigation. The herd had a history of heavy infection with Mycobacterium avium paratuberculosis [MAP] with culling rates of 1.5 and 5%, in 1991 and 1995, respectively. The mean annual losses due to the reduction in milk yield, pregnancy rate and carcass weight was about $32000. In addition, the farm has had positive tuberculin test. During this study, 2070 calves within 31 days of age, were inoculated once subcutaneously, with MERIAL JD attenuated vaccine, in the middle of brisket region. The vaccine protected the herd against JD effectively, so that from 1995 up to the end of 1999, the means of JD culling among 2-year-old vaccinated and unvaccinated cattle were 0.52 and 19.4%, respectively. This vaccination had no side-effects on TB control programme that was conducted by the comparative tuberculin test. In the site of inoculation, fibrocaseous inflammation, while increasing in size, was developed. during 2 years, on the majority of animals, this reaction disappeared; only in less than 1.5% of instances the lesion became tumoral. and permanent. These animals had no clinical abnormality. While inoculating the vaccine, the insertion of vaccine germ contaminated needles in fingers of vaccinators usually caused temporary, hard and painful inflammation. In one occasion, a progressive granuloma caused by vaccine germ was diagnosed histopathologically and treated with suitable antibiotics