Detection of Dirofilaria repens microfilariae in dog’s blood samples and an oral milbemycin oxime/praziquantel formulation efficacy evaluation in the X small animal clinic

Dirofilaria repens is one of the most widespread mosquito borne filarioid which causes cutaneous dirofilariasis in dogs. Cats and other mammals, humans among them, can also be infected. The aim of this study was to detect microfilariae in blood samples of dogs and evaluate efficacy of therapy by using oral formulation containing milbemycin oxime/praziquantel. The study consisted of five parts. The first part was peripheral blood sampling from 1 216 randomized dogs. In the second part of the study all blood samples were examined by simple and modified Knott’s test and the information about dogs was collected. Positive samples were tested by a polymerase chain reaction (PCR). The third part consisted of treatment administration with oral formulation of milbemycin oxime/praziquantel for group A (n=32) and treatment with oral fenbendazole/pyrantel embonate/praziquantel for group B (n=10). In the fourth part of the study we re-examined blood samples using modified Knott’s test 2 weeks later. The last part of study was the treatment administration for group B and re-examination of blood samples by modified Knott’s test was applied 2 weeks later. In 49 out of 1 216 dog blood samples microfilaremia was detected. Due to the failure to fulfil the conditions of the study, 7 dogs were removed from the study. The further study was done with 42 dogs. All of 49 blood samples were tested using PCR and 100 % Dirofilaria repens was identified. It was found out that dirofilariasis is often found in dogs over 4 years of age (p<0,001). Sex and living type predisposition has not been confirmed. Most of the patients were long haired (77,6 %), large and giant breeds and in most cases microfilaremia was found in blood samples in warm season (p