Transmission of Moraxella bovis from Blood Agar Cultures to Hereford Cattle by Face Flies (Diptera: Muscidae)

Abstract

The ability of Musca autumnalis DeGeer to transmit the bacterium Moraxella bovis (Hauduroy) from laboratory cultures to cattle was investigated. Face flies were exposed to M. bovis on blood agar plates for 3 h and were then released in screened pens containing Hereford heifers. Sixteen animals were exposed in four replicated tests. Moraxella bovis was isolated from all animals and 75% of the eyes exposed to infected face flies. The organism was not isolated from 16 animals exposed to noninfected face flies. Eye lesions characteristic of clinical infectious bovine kera to conjunctivitis developed in 7 of the 24 (29%) infected eyes.