title: [Public drinking water supply and egg laying by Aedes aegypti].
abstract: OBJECTIVE
  To evaluate the effect of the quality of publicly supplied water in domestic water tanks on egg laying by female Aedes aegypti.
  
  
  METHODS
  Laboratory study on immature Ae. aegypti, collected from water-tanks in the municipality of Potim, SP, Southeastern Brazil. Each cage contained three types of water in which eggs could be laid: Three choice per test were simultaneously used to deposit the eggs, ovipositor (A) with water collected from a water tank in Taubaté, ovipositor (B) with distilled water (control) and ovipositor (C) water collected from a water tank in the municipality of Potim. Physiochemical parameters were analyzed. The Kruskall-Wallis test was used to analyze the mean number of eggs in each water sample and the Dwass-Steel-Critchlow-Fligner test was used in making comparisons. To evaluate egg laying, an ovipositional activity index was adopted.
  
  
  RESULTS
  A significant difference in the number of eggs was found between the liquid solutions tested (H = 45; p < 0.0001). The number of eggs found in water tank samples originating from deep wells (C), was statistically superior to water samples from water tanks originating from superficial wells (A) (p < 0.0001) and from the Control (C) p < 0.0001. There was no significant difference between the number of eggs in Control (B) and the surface water (A). In all three tests, the first position was the most productive in all tested solutions. Only water sample (C) produced a positive index (0.54), i.e., attractive to egg laying.
  
  
  CONCLUSIONS
  Water quality influences egg laying by Aedes aegypti. The high concentrations of ammonium nitrate in public water supplies suggest that this chemical component was responsible for attracting pregnant female Aedes aegypti to lay eggs in these environments.
authors.forename: Gisela R A Monteiro
authors.initials: GR
authors.lastname: Marques
authors.forename: Leonardo Suveges Moreira
authors.initials: LS
authors.lastname: Chaves
authors.forename: Lígia Leandro Nunes
authors.initials: LL
authors.lastname: Serpa
authors.forename: Marylene de Brito
authors.initials: Mde B
authors.lastname: Arduíno
authors.forename: Francisco José Moreira
authors.initials: FJ
authors.lastname: Chaves
mesh_terms: D000330:Aedes / Q000033:anatomy & histology*; D000818:Animals; D060766:Drinking Water / Q000032:analysis* / Q000469:parasitology; D005260:Female; D006794:Household Articles; D007303:Insect Vectors / Q000254:growth & development; D007814:Larva / Q000254:growth & development; D009032:Mosquito Control / Q000379:methods*; D010058:Oviposition / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D060753:Water Quality; D014881:Water Supply / Q000032:analysis*
chemical_list: D060766:Drinking Water; D014874:Water Pollutants, Chemical