title: Effect of bicozamycin on the eradication of Shiga toxin-producing Escherichia coli in calves.
abstract: Fifty-nine calves, aged 11 days to 9 months, from three farms breeding Japanese Black beef cattle in Miyazaki Prefecture, Japan, were examined for the presence of Shiga toxin-producing Escherichia coli (STEC). A high prevalence of STEC was detected among calves, with 45 (76.3%) animals carrying STEC including different serogroups (O26, O74, O111, O114, O119, O127, O153, O157, and ONT) and toxin types. The number of STEC in the feces was estimated by a combined method involving enumeration of colony-forming units by a plate-most-probable-number (plate-MPN) technique and polymerase chain reaction for the detection of Shiga toxin genes. Fecal shedding ranged from 10(1) to 10(10) MPN/g feces. To evaluate the safety and efficacy of bicozamycin (BCM: previously named as bicyclomycin) in eradicating STEC, 30 calves carrying STEC with or without diarrhea were examined. Fifteen calves were treated orally with BCM (10 mg/kg/day) once daily for 5 days, and the other 15 were untreated. Twenty-four hours after the last dose, fecal specimens were collected from both groups to compare the number of coliforms and STEC with those before treatment. BCM-treated animals had a significantly lower number of coliforms and STEC compared to the untreated calves. The STEC eradication rate was 86.6% (13/15) in the BCM-treated group, compared to 0% (0/15) in the control group. The corresponding cure rates for diarrhea were 87.5 (7/8) and 0% (0/3), respectively. No adverse reactions were observed in the calves during treatment. It is concluded that BCM is an effective agent for the eradication of STEC in calves with or without diarrhea.
authors.affiliation: Department of Veterinary Public Health, Faculty of Agriculture, Miyazaki University, Japan. a0d901u@cc.miyazaki-u.ac.jp
authors.forename: N
authors.initials: N
authors.lastname: Misawa
authors.forename: M
authors.initials: M
authors.lastname: Sueyoshi
authors.forename: R
authors.initials: R
authors.lastname: Uemura
authors.forename: Y
authors.initials: Y
authors.lastname: Kakemizu
authors.forename: K
authors.initials: K
authors.lastname: Kawashima
authors.forename: H
authors.initials: H
authors.lastname: Nagatomo
authors.forename: F
authors.initials: F
authors.lastname: Kondo
authors.forename: T
authors.initials: T
authors.lastname: Murakami
authors.forename: Y
authors.initials: Y
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000627:therapeutic use*; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification / Q000378:metabolism; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D015995:Prevalence; D022603:Shiga Toxins / Q000096:biosynthesis*
chemical_list: D000900:Anti-Bacterial Agents; D019086:Bridged Bicyclo Compounds, Heterocyclic; D022603:Shiga Toxins; C024504:bicozamycin