However, in a seroprevalence study in the south-east of Iran the results showed that seroprevalence rates were decreased with the increasing of age in sheep[15]

However, in a seroprevalence study in the south-east of Iran the results showed that seroprevalence rates were decreased with the increasing of age in sheep[15]. This study showed that the majority of animals in the north-east of Iran were infected with BTV. found to be 89.2%. The highest mCANP prevalence rate was seen in Taybad, Khalil-abad and Torbat-jam (100%) and the least prevalence rate was seen in Jovein (55%). Conclusions The results showed that the majority of animals in the north-east of Iran are infected with SKLB1002 bluetongue virus. High correlation between abortion history and seroposivity emphasize the economical importance of bluetongue virus in the sheep herds of the region. in the family Reoviridae. Twenty-four antigenically distinct serotypes of BTV have been identified worldwide[1]. The BTV are transmitted between ruminants by the bite of certain vector species of value for sheep and goats was 0.001 and 0.012, respectively. Sex didn’t affect the rate of seropositivity ( em P /em =0.75). Table 1 The result of ELISA for bluetongue antibodies in small ruminants of different areas of north-east of Iran. thead CitySheep hr / Goat hr / Seropositivity %PositiveNegativePositiveNegative /thead Kalat122–85.7Kashmar20115194.6Khaf30230195.2Mashad41918284.3Ghuchan10112481.5Mahvelat1127-90.0Jovein119–55.0Roshtkhar2825-94.3Kalat19515773.9Sarakhs561–98.2Taybad23-15-100.0Bajestan13-13196.3Khalil-abad15—100.0Torbat-heydarie28125294.6Bardaskan30512285.7Chenaran15515673.2Dargaz23510380.5Sabzevar44620585.3Gonabad10213479.3Nishaboor62740490.3Fariman50214392.8Torbat-jam52-40-100.0Total603693194589.2 Open in a separate window Table 2 The percentage of bluetongue antibody SKLB1002 positive sheep and goats with and without abortion. thead SpeciesAbortion hr / Totalyesno /thead SheepELIZAPosCount392211603% within abortion92.985.190.0NegCount303767% within abortion7.114.910.0TotalCount422248670% within abortion100.0100.0100.0GoatELIZAPosCount202117319% within abortion91.082.487.6NegCount202545% within abortion9.017.612.4TotalCount222142364% within abortion100.0100.0100.0 Open in a separate window 4.?Discussion In the present study, the seropositivity of sheep and goat for bluetongue was found to be 89.2% (922 out of 1 1?034) which is higher than the reported seroprevalence of 6.57% in south-east of Iran[15], 51.6% in Isfahan[16], 34.7% in west Azerbaijan[17] and 73.5% in Shiraz[18]. Other studies have shown that bluetongue disease occurs worldwide and lead to significant losses in the small ruminant population[10],[17]. In Thailand, a serological study was carried out and exhibited 39.4% and 73.0% seropositive rates in indigenous sheep and goats respectively[19]. Seroprevalence rates up to 90% were detected in some regions of European Turkey[20]. Bluetongue was confirmed in sheep herds located in Germany. The overall herd seroprevalences were estimated at SKLB1002 37.5% in 2006 and 41.5% in 2007[21]. Since vaccination against BT is not done in Iran, antibody indicated direct exposure to the em Orbivirus /em . The distribution of infected animals in Khorasan Razavi province showed the highest prevalence rate in cities near Afghanistan border. Unfortunately no information is usually available regarding bluetongue disease in Afghanistan. Movements of infected animals have been thought to be a source of contamination of blue tongue in new areas[22]. Despite the high seroprivalence of bluetongue in Khorasan Razavi there is no clinical report of the disease in this region. Clinical recognition of the disease depends largely on the presence of highly susceptible sheep breeds, which invariably act as indicator[1],[23]. It is reported that BTV can cause 25% abortion and 50% decrease in fertility in sheep[24]. In the present study there was a significant relation between seroprevalence SKLB1002 rate and abortion history. Hence it emphasizes the importance of the BTV in the herd. There are differences in age susceptibility to clinical disease which, inexplicably vary with different outbreaks. With Australian serotypes, disease occurs in sheep only at the age of 3 years or older[25]. Seroprevalence increases with age, probably a reflection of increased duration of exposure[10]. In the present study the seroprivalence rates were increased with increase of age in sheep and goats. It could be a reason for the disease to be endemic, because newborn lambs could be guarded by maternal immunity. Also, Taylor and Mellor (1994) reported that after bluetongue epidemic in Turkey, the disease became endemic and probability of contamination was much less in sheep up to 2 years old[20]. However, in a seroprevalence study in the south-east of Iran the results showed that seroprevalence rates were decreased with the increasing of age in sheep[15]. This study showed that the majority of animals in the north-east of Iran were infected with BTV. High correlation between abortion history and seroposivity, emphasized the economical importance of BTV in the sheep herds of the region. Acknowledgments This study was supported by a grant (No: 05/09/38671) from the Veterinary Council of Khorasan Razavi. The authors gratefully acknowledge.