title: Mechanical transmission of Trypanosoma vivax in cattle by the African tabanid Atylotus fuscipes.
abstract: An experiment was carried out in Burkina Faso to evaluate the potential for mechanical transmission of Trypanosoma vivax by the African tabanid Atylotus fuscipes. The experiment was carried out in a corral (10 m x 10 m) completely covered by a mosquito net (12 m x 12 m and 2.5m high). Eight heifers (cross-bred Zebu X Baoulé), free of trypanosome infection, were kept together with two heifers experimentally infected with a local stock of T. vivax. An average of 539 A. fuscipes per day, freshly captured with two Nzi traps, were introduced into the mosquito net from Day 1 to 20, to allow mechanical transmission of the parasites among cattle. Daily parasitological examinations (BCM) of cattle blood samples indicated that six of the eight receiver heifers were positive from days 9, 10, 15, 16, 19 and 29. Mechanical transmission of T. vivax by A. fuscipes was demonstrated unequivocally in close to natural conditions, at a high rate (75% incidence over a 20-day period) under a mean challenge of 54 insects per heifer per day. These results, in addition to previous demonstration of mechanical transmission of T. vivax by Atylotus agrestis, confirm that mechanical transmission can be a significant route of infection.
authors.affiliation: CIRAD-EMVT, Centre de coopération Internationale en Recherche Agronomique pour le Développement--département Elevage et Médecine Vétérinaire Tropicale, Montpellier, France. m.desquesnes@fasonet.bf
authors.forename: Marc
authors.initials: M
authors.lastname: Desquesnes
authors.forename: Mamadou Lamine
authors.initials: ML
authors.lastname: Dia
mesh_terms: D000818:Animals; D002050:Burkina Faso; D002417:Cattle; D002418:Cattle Diseases / Q000469:parasitology* / Q000635:transmission*; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D004175:Diptera / Q000469:parasitology*; D005260:Female; D006400:Hematocrit / Q000662:veterinary; D007299:Insect Bites and Stings / Q000469:parasitology; D007303:Insect Vectors / Q000469:parasitology*; D018512:Parasitemia / Q000469:parasitology / Q000662:veterinary; D016133:Polymerase Chain Reaction / Q000662:veterinary; D016689:Trypanosoma vivax / Q000235:genetics / Q000254:growth & development*; D014353:Trypanosomiasis, African / Q000469:parasitology / Q000635:transmission* / Q000662:veterinary*
chemical_list: D016054:DNA, Protozoan