First report of predation of Giardia sp. cysts by ciliated protozoa and confirmation of predation of Cryptosporidium spp. oocysts by ciliate species.
Ciliated protozoa are important components of the microbial food web in various habitats, especially aquatic environments. These organisms are useful bioindicators for both environmental quality assessment and the wastewater purification process. The pathogenic parasitic protozoan species Giardia and Cryptosporidium represent a significant concern for human health, being responsible for numerous disease outbreaks worldwide. The predation of cysts and oocysts in 15 ciliate species from water and sewage samples collected in Campinas, São Paulo, Brazil were verified under laboratory conditions. The ciliated protozoan species were selected based on their mode of nutrition, and only bacterivorous and suspension-feeders were considered for the experiments. The species Blepharisma sinuosum, Euplotes aediculatus, Sterkiella cavicola, Oxytricha granulifera, Vorticella infusionum, Spirostomum minus, and Stentor coeruleus ingested cysts and oocysts, the resistance forms of Giardia spp. and Cryptosporidium spp., respectively. This is the first time that the ingestion of Giardia cysts by ciliated protozoa has been reported. These findings may contribute to a better understanding of the biological removal of these pathogens from aquatic environments.
Protozoology Laboratory, Biology Institute, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil. siqueiraicv@gmail.com.|Cidade Universitária Zeferino Vaz, Rua Monteiro Lobato 255, CEP 13.083-862, Campinas, SP, Brazil. siqueiraicv@gmail.com.
Isabel Cristina Vidal
ICV
Siqueira-Castro
Protozoology Laboratory, Biology Institute, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.|Parasitology Laboratory, Regional University of Blumenau (FURB), Blumenau, SC, Brazil.
Juliane Araújo
JA
Greinert-Goulart
Protozoology Laboratory, Biology Institute, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
Tais Rondello
TR
Bonatti
Protozoology Laboratory, Biology Institute, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
Sandra
S
Yamashiro
Protozoology Laboratory, Biology Institute, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
Regina Maura Bueno
RMB
Franco
D000818:Animals; D001938:Brazil; D016798:Ciliophora / Q000254:growth & development* / Q000502:physiology; D003458:Cryptosporidium / Q000302:isolation & purification*; D017753:Ecosystem; D005247:Feeding Behavior; D005872:Giardia / Q000302:isolation & purification*; D006801:Humans; D008856:Microscopy, Fluorescence; D033661:Oocysts; D045483:Rivers / Q000469:parasitology*; D012722:Sewage / Q000469:parasitology*; D062065:Wastewater / Q000469:parasitology
D012722:Sewage; D062065:Wastewater
Ciliated protozoa; Cryptosporidium oocysts; Giardia cysts; Predation