EN
The increasing number of dogs, including stray ones, was the reason for carrying out the pilot study on the extensiveness of verminous invasion in these animals in four central and 7 suburban quarters of Olsztyn. Fresh samples of faeces taken from 220 dogs, coming from 20 animals from each district, were examined for the presence of parasite eggs and segments of tapeworms and adults nematode forms. The studies revealed mainly the presence of nematodes and to a smaller degree the segments of Diphylidium caninum (1.3%). The extensiveness of parasite invasion commonly ranged from 10 to 45%. Toxocara canis occurred most frequently (11.8%). Moreover, eggs of Ancylostomatidae (2.7%), Toxascaris leonina (1.8%) and Trichocephalus vulpis (1.3%) were found. One can conclude that due to their carrier state of parasites, dogs in towns and cities may constitute a potential health hazard for the inhabitants. This fact is all the more significant since only a small number of animals show clinical signs of infestation.