Oocyst


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Related to Oocyst: cryptosporidium

oocyst

[′ō·ə‚sist]
(invertebrate zoology)
The encysted zygote of some Sporozoa.

Oocyst

 

one of the stages in the development of protozoans of the class Sporozoa. The oocyst forms as a result of the encyst-ment of a fertilized egg cell. It is covered with a strong protective membrane. The contents of the oocyst generally divide into several nonmotile spores (in Coccidia) or motile sporozoites (in Gregarinidia). In Hemosporidia the oocyst produces thousands of sporozoites, which subsequently leave the oocyst.

References in periodicals archive ?
oocysts are required to infect a child, for obvious reasons, a study that was conducted with pigs found that a single oocyst was sufi[logical not]cient to cause infection in 13 of 14 experimentally infected pigs," the authors wrote.
parvum is probably present in every domestic horse herd in the world with asymptomatic infections and prolonged oocyst excretion by adult horses recognized as a major and continuous source of environmental contamination [15].
A small amount of water was added to the bottom of the cage to keep the feces moist and the oocyst viable.
We were unable to obtain the number of sporozoites formed in the oocyst.
The oocyst and sporozoite rates (95% CI) of members of An.
While chlorine can kill oocysts, it takes higher levels and more time than is possible for pool sanitizing systems.
Most mosquitoes had few or no oocysts in their guts.
The approach considered in this report is to quantify and type oocyst sources in watersheds and compare those with isolates from human patients.
oocyst per 1,600 litres of drinking-water to achieve a health-outcome target of 10-6 DALYs per person per year (23).