Objective: In the present study, the aim is to demonstrate Cryptosporidium parvum 18S small-subunit rRNA gene, in lung and stool samples of immune suppressed rats. This gene region is specific for Cryptosporidium spp. and thus can be used in humans for routine diagnostic procedures.
Methods: Three groups (n=4) of Rattus norvegicus rats were used. The first and second groups were administered dexamethasone, subcutaneously and orally, respectively, for 12 weeks. Rats in the control group were not immune suppressed. Lung and stool specimens were obtained from rats at the end of 12 < sup > th < /sup > week and examined for the presence of C. parvum DNA using Nested PCR.
Results: C. parvum DNA was demonstrated in lung and stool samples of rats which were immune suppressed by oral dexamethasone. On the other hand, C. parvum DNA was demonstrated only in stool specimens of the rats which were immune suppressed by subcutaneous dexamethasone. No band pattern was observed in the specimens of the control group.
Conclusion: The results of the study showed that oral dexamethasone administration was more efficient in generating disseminated cryptosporidiosis in rats compared to subcutaneous dexamethasone administration. In addition, Nested PCR targeting 18S small-subunit rRNA gene can be used to detect Cryptosporidium spp. in respiratory and stool specimens of animals and humans.