Ascariasis of domestic and wild carnivores in urban and natural populations

The purpose of the research is to assess the current prevalence of ascaridosis in carnivores in Moscow and the surrounding region.

Materials and methods. A total of 7 064 fecal samples from animals were analyzed: 4 044 – from a domestic dog, 322 – from shelter dogs, 2 399 – from a domestic cats, 171 – from shelter cats, 54 – from carnivores from hunting grounds, 74 – from animals kept in zoos in Moscow and the Moscow region. The samples were analyzed using a combined flotation method and formalin-acetate sedimentation. Complete helminthological necropsies were performed on 76 animals.

Results and discussion. Ascariasis was detected in both dogs and cats from urban populations, foxes, lynxes and large cats from zoos. Two species of roundworm were detected in canines: Toxocara canis and Toxascaris leonina; in felines, Toxocara cati and T. leonina. The overall prevalence of roundworm infection in shelter dogs was higher than in domestic dogs. Domestic dogs were more frequently infected with Toxocara (2.1%) than with Toxascaris (0.5%). In shelter dogs, T. leonina was detected (9.3%), while T. canis was less frequently detected (5.6 %). A particularly high infection rate (50.0 %) was found in shelter puppies. Among both domestic and shelter dogs, the prevalence of roundworm infection in puppies was higher than in adult animals. Foxes from hunting grounds were more frequently infected with T. leonina (44.7% in fecal samples and 55.4% in necropsy samples), while T. canis was less common (19.2% and 32.1%, respectively). The overall infection rate of cats in shelters was higher than that of pet cats. Shelter cats were infected with only one species of roundworm – T. cati (9.9%). T. leonina was more frequently detected in zoo cats (47.9%) than T. cati (12.5 ). Zoo cats were more likely to be infected with T. cati than pet cats, but were not statistically different from shelter cats. According to coprological studies, feline infections with Toxocara are higher than canine infections.

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