title: Whole-flock, metaphylactic tilmicosin failed to eliminate contagious ovine digital dermatitis and footrot in sheep: a cluster randomised trial.
abstract: The aim of this study was to evaluate the clinical success of whole-flock systemic tilmicosin and enhanced biosecurity in eliminating active contagious ovine digital dermatitis (CODD) from sheep flocks. Thirty flocks in the UK were randomly allocated to receive either treatment as usual (as per the farmer's normal routine) or whole-flock treatment with tilmicosin, together with isolation and extended treatment of clinically affected individuals and isolation and treatment of purchased sheep during the study period. All flocks were visited once at onset of the trial to examine all sheep. One year later, all sheep were re-examined to determine the presence/absence of clinical lesions. The primary outcome was the clinical elimination of CODD from flocks. Secondary outcomes were reduction in prevalence of CODD, clinical elimination of footrot and reduction in prevalence of footrot. The analysis included 11 control flocks and 13 intervention flocks, with initially 3460 and 4686 sheep, respectively. For CODD: at follow-up, in the intervention group, 6/13 (46 per cent) flocks had a prevalence of zero compared with 1/11 (9 per cent) in the control group (P=0.12). For footrot: at follow-up, no flocks had a prevalence of zero. Therefore, the intervention is not recommended for the elimination of CODD or footrot in the UK.
authors.affiliation: Department of Epidemiology and Population Health, Institute of Infection and Global Health, The University of Liverpool, Leahurst Campus, Neston, Wirral CH64 7TE, UK.
authors.forename: J W
authors.initials: JW
authors.lastname: Angell
authors.affiliation: Department of Epidemiology and Population Health, Institute of Infection and Global Health, The University of Liverpool, Leahurst Campus, Neston, Wirral CH64 7TE, UK.
authors.forename: D H
authors.initials: DH
authors.lastname: Grove-White
authors.affiliation: Leahurst Farm Animal Practice, The University of Liverpool, Leahurst Campus, Neston, Wirral CH64 7TE, UK.
authors.forename: H J
authors.initials: HJ
authors.lastname: Williams
authors.affiliation: Department of Epidemiology and Population Health, Institute of Infection and Global Health, The University of Liverpool, Leahurst Campus, Neston, Wirral CH64 7TE, UK.
authors.forename: J S
authors.initials: JS
authors.lastname: Duncan
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016000:Cluster Analysis; D058066:Digital Dermatitis / Q000188:drug therapy* / Q000453:epidemiology; D005535:Foot Rot / Q000188:drug therapy* / Q000453:epidemiology; D012756:Sheep; D012757:Sheep Diseases / Q000188:drug therapy* / Q000453:epidemiology; D016896:Treatment Outcome; D015645:Tylosin / Q000031:analogs & derivatives* / Q000627:therapeutic use; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; C052319:tilmicosin; D015645:Tylosin
keywords: Footrot; Sheep; contagious ovine digital dermatitis; tilmicosin; whole-flock treatment