title: Topically applied benzathine cloxacillin for treatment of experimentally induced infectious bovine keratoconjunctivitis.
abstract: The efficacy of an ophthalmic ointment containing benzathine cloxacillin for treatment of infectious bovine keratoconjunctivitis was determined in 2 experiments. In the first experiment, Holstein calves (n = 6/group) were inoculated with Moraxella bovis and treated on postinoculation days 3 and 6 with either topically applied benzathine cloxacillin (250 mg/eye) or long-acting oxytetracycline formulation (20 mg/kg of body weight, IM). A third group of inoculated calves remained untreated as controls. For the second experiment, 4 groups of calves (n = 6/group) were inoculated and treated on postinoculation days 3 and 6 with 50, 125, 250, or 375 mg of benzathine cloxacillin; a fifth untreated group served as controls. Ocular specimens were obtained for microbiologic culture, and eyes were observed and assigned a clinical score daily. Eyes were photographed on alternate days. Ulcer surface area was measured, using a planimeter. In experiment 1, the week-2 ulcer surface area measurements for both groups of treated calves were smaller than those for controls. There was a greater frequency of M bovis isolation from the ocular secretions of controls than from those of benzathine cloxacillin-treated calves during postinoculation weeks 2 and 3. The number of M bovis isolations from the benzathine cloxacillin- and oxytetracycline-treated calves was not significantly different at any sample collection interval. On week 3, the scores of the benzathine cloxacillin-treated calves were smaller than those of controls. In experiment 2, calves of the 250- and 375-mg groups had smaller ulcer surface area measurements than did controls on week 2. By week 3, calves of the 375-mg group had smaller scores than did controls.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Medicine, College of Veterinary Medicine, University of California, Davis 95616.
authors.forename: J
authors.initials: J
authors.lastname: Daigneault
authors.forename: L W
authors.initials: LW
authors.lastname: George
mesh_terms: D000287:Administration, Topical; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy* / Q000209:etiology; D003023:Cloxacillin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D007639:Keratoconjunctivitis, Infectious / Q000188:drug therapy* / Q000209:etiology; D008297:Male; D009016:Moraxella / Q000302:isolation & purification
chemical_list: C006692:benzathine cloxacillin; D003023:Cloxacillin