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Related to oocyst: cryptosporidium


A thick-walled structure that contains the zygote of an apicomplexan parasite and releases the infective sporozoites.


(Zoology) an encysted zygote of sporozoan protozoans that undergoes sporogony to produce infective sporozoites


(ˈoʊ əˌsɪst)

the encysted zygotic stage in the life cycle of some sporozoans.
References in periodicals archive ?
A possible cause of finding oocysts in calves of 1 day of age has been referred to by Romero et al (4) involving the teats of the mother as a major source of infection by being contaminated with oocyst of Cryptosporidium spp.
parasite is at a hardy stage of its life cycle called an oocyst, a tiny bundle of a few cells.
5] reported 22% fecal oocyst positive rate out of 230 out patients of private hospital and Chai et al.
This study was designed to determine the effects of a high fat, high protein, or high fiber diet on oocyst production of E.
The oocysts are oval, 26,3-29,4 x 15,1-17,6, enclosed in a conspicuous border (envelope, limiting wall), the undifferentiated oocyst contents are vacuolated (foamy) and show a denser central mass (Figs.
After ingestion by a calf, a single oocyst (coccidial egg) can multiply to up to 24 million oocysts, which are then shed into the environment, posing a risk to all in-contact calves and future generations.
The infective stages are four naked sporozoites enclosed in a spherical, thick wall oocyst (measuring 4-6 [micro]m and lacking the sporocyst), which enables the parasite to survive for months outside the host (Fayer et al.
There were no significant differences in oocyst rate among An.
It has a complex life cycle; its infectious stage is the spherical oocyst.
Next, Vernick's team scanned the mosquitoes' DNA for markers that might correlate with a heavy oocyst presence.
In other cases, boil water advisories have been issued when oocyst numbers from watersheds reached levels of concern.