| Abstrakt: |
AbstractDue to concern over an outbreak of bluetongue disease in cattle near Osoyoos, B.C., a survey of Culicoidesspp. was made and the seasonal and immediate geographical distribution of the known large-mammal biting species studied. Species found included C. cockerelli(Coquillett),C. crepuscularisMalloch, C. near haematopotus, C. jamesiFox, C. montanusWirth and Blanton, C. obsoletus(Meigen), C. occidentalisWirth and Jones, C. palmeraeJames, C. piliferusgroup, C. travisigroup, C. variipennis(Coquillett), C. yukonensisHoffman, and Leptoconops kertesziKeiffer. The active period for adults of C. occidentalis, a proved vector of bluetongue disease, is from mid-April through early October. Breeding sites of this species were common from 275 to 600 m above sea level throughout the area of bluetongue disease incidence. Breeding sites extended up to 1350 m and adults were trapped at 1820 m. A large number of adult C. occidentalisand other Culicoidesspp. were collected for isolation of bluetongue virus. No virus was recovered. This was possibly due to large-scale testing of susceptible domestic animals for bluetongue virus antigens and removal of those giving positive reactions prior to collection of the insects tested. |
