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Related to Oocyst: cryptosporidium


(invertebrate zoology)
The encysted zygote of some Sporozoa.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



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.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Greater intensity and frequency of Cryptosporidium and Giardia oocyst shedding beyond the neonatal period is associated with reductions in growth, carcase weight and dressing efficiency in sheep.
Among notable characteristics for Cyclospora is the oocyst's pronounced resistance to most chemical disinfectants, including chlorine.
The parasite can be transmitted to humans and animals mainly through: the fecal-oral route, through the ingestion of oocysts that may be present in contaminated water, soil and vegetables; consumption of raw or undercooked meat and animal products containing tissue cysts; and transplacental route (FRENKEL et al, 1970).
Toxoplasma gondii infection in cats from Sao Paulo state, Brazil: seroprevalence, oocyst shedding, isolation in mice, and biologic and molecular characterization.
Carpentieri et al., "Evidence for a structural role for acid-fast lipids in oocyst walls of cryptosporidium, Toxoplasma, and Eimeria," mBio, vol.
Table 6 summarizes the effects of respective treatments on oocyst shedding (as an indicator of efficacy) with time.
Morphologically, the oocysts are spherical to ovoid and do not present a micropyle.
Microscopy of the stool sample was done, by subjecting the stool sample for saline and iodine mount preparation, for identification of trophozoite forms, eggs and oocyst and other infective agents.
In other Asian countries, the parasite has been encountered in tap water as little as one oocyst from 115 samples [24].
The beta-glucans also had protective effects against Eimeria infection and significantly improved weight gains of chickens with few lesions and oocyst score.
(2005) who recorded 41 per cent reduction in oocyst output in Coxabic[R] vaccinated chickens, however, 23.5 per cent reduction in mean OPG of E.
Results showed the equipment efficacy of pure berberine to that of standard drug amprolium on the basis of oocyst count per gram of faeces (Fig.