title: Palatability and efficacy of bromadiolone rodenticide block bait previously exposed to environmental conditions.
abstract: BACKGROUND
  In São Paulo city, rodent infestation is considered to be a serious public health problem and is the object of a municipal rodent control programme. One of the most important routine methods involves baiting in sewers, using bromadiolone block bait in a pulsed baiting strategy. It has been observed that, after each pulse, bait is not always consumed, and its appearance is altered, which has led to concerns about efficacy. We assessed whether exposure to sewer conditions influences the palatability and efficacy of rodenticide baits to Norway rats (Rattus norvegicus). Baits containing bromadiolone as active ingredient were placed in sewers, removed after 30 days and offered to rats in a two-choice food trial and a no-choice food trial.
  
  
  RESULTS
  The appearance of the rodenticide baits changed after 30 days exposure to sewer conditions, but they continued to be palatable and effective against rats. The level of mortality was considered to be satisfactory, 75% in the two-choice food trial and 100% in the no-choice food trial.
  
  
  CONCLUSIONS
  Results support the reuse of rodenticide block bait in rodent control. It seems to be justified to continue using/reuse baits even when their appearance has changed after 30 days exposure in sewer systems.
authors.affiliation: Biological Institute, Environmental Protection Centre, São Paulo, SP, Brazil.
authors.forename: Lia
authors.initials: L
authors.lastname: Nakagawa
authors.affiliation: Municipality of São Paulo, Municipal Health Secretary, São Paulo, SP, Brazil.
authors.forename: Eduardo
authors.initials: E
authors.lastname: de Masi
authors.affiliation: Biological Institute, Environmental Protection Centre, São Paulo, SP, Brazil.
authors.forename: Emerson
authors.initials: E
authors.lastname: Narciso
authors.affiliation: Municipality of São Paulo, Municipal Health Secretary, São Paulo, SP, Brazil.
authors.forename: Hildebrando Montenegro
authors.initials: HM
authors.lastname: Neto
authors.affiliation: Municipality of São Paulo, Municipal Health Secretary, São Paulo, SP, Brazil.
authors.forename: Solange
authors.initials: S
authors.lastname: Papini
mesh_terms: D015110:4-Hydroxycoumarins / Q000633:toxicity*; D000818:Animals; D005247:Feeding Behavior / Q000187:drug effects; D005260:Female; D008297:Male; D051381:Rats / Q000502:physiology*; D012375:Rodent Control / Q000295:instrumentation / Q000379:methods*; D012378:Rodenticides / Q000633:toxicity*
chemical_list: D015110:4-Hydroxycoumarins; D012378:Rodenticides; C021636:bromadiolone
keywords: bromadiolone; environmental protection; hydroxycoumarin; integrated pest management; rodent control; rodenticide