Kd. Sargent et al., MORPHOLOGICAL AND GENETIC-CHARACTERIZATION OF CRYPTOSPORIDIUM OOCYSTSFROM DOMESTIC CATS, Veterinary parasitology, 77(4), 1998, pp. 221-227
Faecal samples were collected from domestic cats in the metropolitan a
rea of the city of Perth, Western Australia, and screened for the pres
ence of Cryptosporidium by both microscopy and PCR. Of 162 samples scr
eened, two were positive for Cryptosporidium (a prevalence of 1.2%). S
ample Ct33 was from an 18-month-old female and sample Ct131 from a 12-
month-old female. Morphological studies revealed oocysts with an avera
ge size of 4.6x4.0 mu m, smaller in size than isolates typically seen
in humans (5.0x4.5 mu m). Sequence analysis of PCR products showed seq
uences from cat isolates to be different to previously sequenced human
and calf isolates, with cat isolates exhibiting 8.1% sequence diverge
nce from these isolates. Phylogenetic analysis grouped the cat isolate
s into a distinct group, separate from other C. parvum isolates and Cr
yptosporidium species. These results lend support to the existence of
a cat-adapted Cryptosporidium strain or species. (C) 1998 Elsevier Sci
ence B.V.