Epidemiological Investigation On Bluetongue And Analysis On It’s Transmission Media Distribution In Inner Mongolia

Bluetongue disease is an infectious disease caused by bluetongue virus, which spread its pathogen by biting ruminants by Culicoides. The bluetongue disease has been classified as A level animal epidemics by the Organisation Internationale des Epizooties (OIE), and ranked as the first standard in China. Culicoides has been recognized as the media of the bluetongue disease all over the world. Up to now, there are 125 genera and 5360 species in the world, only a small part of them have the ability to spread the bluetongue disease. There are 4 genera and 1671 species of sucking-blood midges discovried in the world, and 3 genera and 414 species of them were known in China. In recent years, due to the globe warming, the insect activity seasons and reproduction time are getting longer, which has being in larger medium quantity.In this epidemiological investigation,6199 sheep serums and anticoagulants and 796 cattle serums and anticoagulants were collected from 11 leagues and cities in Inner Mongolia (Alxa League, Wuhai City, Bayannur League, Erdos City, Baotou City, Hohhot City, Ulanqab City, Chifeng City, Xilin Gol League, Tongliao City, Hinggan League) from June,2013 to February,2015. The result shows that,2199 sheep were tested positive, which the infection rate was of 35.47%, and 93 cattle were tested positive, which the infection rate of 11.68%. And other factors including species, ages, genders and regions were compared analying the difference between serums and anticoagulants.The light trap method and swing net capture method were used to capture the Culicoides from 8 areas including Alxa League, Bayannur league, Erdos City, Hohhot City, Chifeng City, Xilin Gol League, Tongliao City, Hinggan League. The results shown that 7 species of Culicoides had been identified, which were Culicoides punctatus, Culicoides circumscriptus.Culicoides mongolensis, Culicoides peregrines, Culicoides oxystoma, Culicoides orientalis and Culicoides actoni. The quantities of Culicoides punctatus, Culicoides circwmscriptus and Culicoides mongolensis were 332,276 and 231 respectively, which ranked as the dominant population in this area.