Abstract:

Objective To understand the prevalence patterns and epidemiological characteristics of intestinal parasitic infections in dogs and cats in Chengdu area, and provide scientific evidence for targeted prevention and control of parasitic infections in local pets. Methods From July to September 2025, we selected two residential communities, two pet stores and one veterinary clinic as survey sites in Chengdu City by stratified sampling, and collected fresh fecal samples of dogs and cats aged ≥3 months from household, for-sale/boarding and outpatient. Intestinal parasites were detected by modified Kato-Katz thick smear, iodine staining and normal saline smears. The parasitic infection status in pets with different species and breeding scenarios was analyzed. Results A total of 750 fecal samples of dogs and cats were harvested. The total infection rate was 9.07% (68/750), among which the infection rate of dogs was 10.29% (36/350), and that of cats was 8.00% (32/400). There was no statistically significant difference (χ²=1.18, P>0.05). The overall infection rates of dogs and cats in outpatient, household, and for-sale/boarding were 11.14% (39/350), 12.00% (24/200) and 2.50% (5/200), respectively, with a statistically significant difference (χ²=14.38, P<0.001). A total of 4 intestinal protozoan species (Tritrichomonas foetus, Isospora, Blastocystis spp. and Giardia lamblia) and 8 helminth species (roundworm, Dipylidium caninum, Spirometra mansoni, hookworm, Trichuris trichura, Alaria spp., Paragonimus spp.and Capillaria spp.) were detected. The infection rates of Tritrichomonas foetus (1.73%) and roundworm (1.60%) were relatively high. Monospecific infection was predominant in all positive cases (91.18%, 62/68), among which 64.52% (40/62), 35.48% (22/62) of the infections were involved respectively in intestinal protozoa and intestinal helminths. Mixed infections accounted for 8.82% (6/68), dominated by co-infection with two parasite species (5 cases). In terms of the animals fed in different environments, four protozoan species were detected in household dogs and cats, three species in pets from veterinary clinics, yet no protozoa were detected in pets for sale or in boarding care. For intestinal helminths, three helminthic species were identified in clinic dogs, five in clinic cats, and five in household dogs, whereas only roundworms were detected in pet cats as well as in both dogs and cats for sale or at boarding conditions. Mixed infections only occurred in pets from veterinary clinics. Conclusion Intestinal parasite infections in dogs and cats in Chengdu City are diverse with evident zoonotic risks. The infection rate is strongly related to housing scenarios. Our findings suggest that it is necessary to develop scenario-targeted control strategies and strengthen pet owners' awareness of epidemic prevention and encourage regular deworming.

Key words: Dog, Cat, Intestinal parasites, Protozoon, Helminth, Infection status, Chengdu City