Distribution of Intestinal Worms among Stray Dogs in Isfahan, Iran

Zoonotic diseases have always threatened humans. They are common between human and many animals. Large numbers of dogs, especially stray dogs, are born every year. In addition, they inhabit around the cities and people's residences. Therefore, they have always been considered as threats for human health and environment. Identification of parasites in stray dogs around Isfahan, Iran would have economic, medical, veterinary, and particularly zoonosis benefits. In this study, 96 killed stray dogs were collected from several regions of Isfahan. After autopsy in place, the two ends of animal's bowel were closed and the intestines were moved to the laboratory. The intestines were opened longitudinally, washed with water, and examined for the presence of worms. The worms isolated from water were then transferred to a 10% formaldehyde solution. After temporary and permanent staining and transparency of isolates, the appropriate isolates were mounted and prepared for taxonomic study. The shapes of all samples were drawn by a drawing tube. They were then identified by diagnostic keys such as length of large hook, shape of proglottid, and characteristics of mature worms like cirrus sucks and the positions of testis. Nematode body length, the cuticle, cephalic and caudal fins, number of lips, morphology of esophagus, and position of rectum and vagina were also evaluated as crucial properties in taxonomic study. All isolates were identified at genus and species levels. In this study, 96 dogs were examined. Overall, 60.4% intestinal samples of stray dogs were infected with at least one isolated worm. The isolates included a total of seven species of cestodes and three species of nematodes. The identified cestodes consisted of 24% Taenia ovis, 13.54% T. hydatigena, 5.21% T. pisiformis, 5.21% T. multiceps, 27.1% Echinococcus granulosus, 22.92% Dipylidium caninum, 5.21% Mesocestoides lineatus. The nematodes were categorized as 21.9% Toxascaris leonina, 6.25% Toxocara canis, 3.13% Rictularia affini Taenia pisiformis was reported for the first time in the province of Isfahan. Our findings reveal the role of parasites in medical and veterinary aspects. Pet dogs and sheepdogs are thus required to be treated properly. On the other hand, stray dogs should be killed and the infected bodies need to be destroyed.