A comparative study on Cryptosporidium infection in household and stray dogs in Urmia and Tabriz municipalities, Iran

Cryptosporidium is an important intestinal pathogenic protozoan of livestock and human worldwide. The present study was carried out to compare Cryptosporidium infection in dogs of Urmia and Tabriz municipalities, Iran. A total of 300 fecal samples were collected from stray dogs and domestic dogs of the regions. Cryptosporidium oocysts were removed using floatation method and purified with sucrose and Percoll gradients. Finally, the slides were stained using modified Ziehl-Neelsen technique. Microscopically, overall prevalence was 1% (3/300) with distributions of 0.67% (1/150) and 1.33% (2/150) in Tabriz and Urmia, respectively. There was no cryptosporidial infection in household dogs. The highest infection rate was found in stray dogs less than 1 year old (0.66%, 1/150). In the infected dogs, the consistency of feces was diarrheal and soft. There was no significant association between season and prevalence. The results indicated that Cryptosporidium infection existed in dogs of Tabriz and Urmia municipalities with low prevalence. It is necessary as a zoonotic agent to do further investigations on Cryptosporidium species diversity and genotypes in human and animal populations of northwestern Iran.