Molecular detection of Cryptosporidium spp. and the occurrence of intestinal parasites in fecal samples of naturally infected dogs and cats

Cats and dogs are hosts of a large number of gastrointestinal parasites and can shed helminth eggs and protozoan oocysts in their feces. The close relationship between companion animals and humans intensifies human exposure to zoonosis caused by parasites. In this study, 177 fecal samples were collected: 128 from dogs and 49 from cats of both sexes and varied ages. One or more intestinal parasites were observed in 56.2% (72/128) of the dog fecal samples and in 53.0% (26/49) of the cat fecal samples. Parasitic monoinfection was present in 70.8% (51/72) of dog samples and in 46.1% (12/26) of cat samples, whereas multi-infection was observed in 29.2% (21/72) and 53.8% (14/26) of dog and cat samples, respectively. The detection frequency of Cryptosporidium spp. was 22.6% (40/177) using Ziehl-Neelsen staining. DNA was extracted from all samples and the Cryptosporidium small subunit ribosomal ribonucleic acid (SSU rRNA) gene was amplified from 5.6% (10/177) of the fecal samples using nested polymerase chain reaction (PCR). Amplification was achieved in 4.6% (6/128) of the dog samples and in 8.2% (4/49) of the cat samples. DNA sequencing of the nested PCR positive samples identified Cryptosporidium canis in 66.6% (4/6) and Cryptosporidium parvum in 33.3% (2/6) of the dog samples and Cryptosporidium felis in 75% (3/4) and Cryptosporidium parvum in 25% (1/4) in the cat samples. The present study thus demonstrated significant levels of gastrointestinal parasite infection in companion animals and highlighted the presence of zoonosis agents.