title: Comparison of animal infectivity and nucleic acid staining for assessment of Cryptosporidium parvum viability in water.
abstract: Cryptosporidium parvum oocysts were stained with the fluorogenic dyes SYTO-9 and SYTO-59 and sorted by flow cytometry in order to determine whether the fluorescent staining intensity correlated with the ability of oocysts to infect neonatal CD-1 mice. Oocysts that did not fluoresce or that displayed weak fluorescent intensity when stained with SYTO-9 or SYTO-59 readily established infections in mice, whereas those oocysts that fluoresced brightly did not. Although fluorescent staining profiles varied among different batches of oocysts, a relative cutoff in fluorescent staining intensity that correlated with animal infectivity was observed for all batches.
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Canada.
authors.forename: N F
authors.initials: NF
authors.lastname: Neumann
authors.forename: L L
authors.initials: LL
authors.lastname: Gyürek
authors.forename: L
authors.initials: L
authors.lastname: Gammie
authors.forename: G R
authors.initials: GR
authors.lastname: Finch
authors.forename: M
authors.initials: M
authors.lastname: Belosevic
mesh_terms: D000818:Animals; D004396:Coloring Agents / Q000378:metabolism; D003457:Cryptosporidiosis / Q000469:parasitology*; D016785:Cryptosporidium parvum / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity*; D051379:Mice; D018613:Microscopy, Confocal; D009696:Nucleic Acids / Q000032:analysis*; D009930:Organic Chemicals; D013194:Staining and Labeling; D014881:Water Supply
chemical_list: D004396:Coloring Agents; D009696:Nucleic Acids; D009930:Organic Chemicals; C103389:SYTO 9