Infectivity of preserved Cryptosporidium parvum oocysts for immunosuppressed adult mice.
The present study was undertaken to determine the infectivity of Cryptosporidium parvum oocysts for immunosuppressed adult C57BL/6N mice after the oocysts had been stored from 1-48 months at 4 degrees C in 2.5% potassium dichromate. All mice inoculated with oocysts 1-18 months old developed patent infections, while mice inoculated with older oocysts remained uninfected. The prepatent period was extended from 2 to 6 or 7 days as the storage time for oocysts increased. The finding that C. parvum oocysts remain infective for mice for at least 18 months offers important economic and time-saving advantages for investigators who frequently require large numbers of oocysts that must be painstakingly purified from calf manure.
Yang
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Department of Animal, Dairy and Veterinary Sciences, Utah State University, Logan 84322-5600, USA.
Healey
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MC
Du
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C
D000818:Animals; D003457:Cryptosporidiosis / Q000469:parasitology* / Q000473:pathology; D016785:Cryptosporidium parvum / Q000254:growth & development* / Q000472:pathogenicity*; D003907:Dexamethasone / Q000494:pharmacology; D005243:Feces / Q000469:parasitology; D005260:Female; D007082:Ileum / Q000469:parasitology; D016867:Immunocompromised Host; D051379:Mice; D008810:Mice, Inbred C57BL; D011309:Preservation, Biological
D003907:Dexamethasone