Seasonal study of Blood Parasites: <i>DirofilariaImmitis</i> and <i>Dipetalonema Reconditum</i> in the Guard Dogs of Tabriz city, Iran.

Dirofilariasis, also known as canine heartworm disease, is one of the most dangerous invasive diseases in dogs. Invasion caused by <i>Dirofilaria immitis</i> is the most critical case. Filarial infection has been observed worldwide, involving different agents and species of nematodes.However, <i>D. immitis</i> is more important than other species in dogs. For this study, one hundred guard dog collars were examined from dogs that visited small animal clinics of Tabriz, Iran during the summer of 2023 (May, June, and July), because blood parasites are more prevalent in dogs in summer. A total of 100 blood samples from guard dogsof various ages, sexes, and breeds were examined for blood parasites. Of these, 70 were adult dogs, 30 were puppies, 35 were females, and 65 were males. The prevalence of blood parasites in the dogs was determined using wet blood smear, a centrifuge hematocrit, and modified Knott's technique. The blood parasites found in this study were <i>D. immitis</i>, Dipetalonema reconditum. Out of 100 guard dogs, 9 dogs (9%) were found to be infected with blood parasites. The prevalence of <i>D. immitis</i> and <i>D. Reconditum</i> in our study was 7% and 2%, respectively. Two out of thirty puppies (6.6%) were infected with blood parasites, and in the group of adult dogs, 7 collars out of 70 dog collars (10%) were infected with blood parasites. The highest infection percentage recorded was related to <i>D. immitis</i> with 7 collars (7%) out of 100 cases were positive. The findings showed the highest prevalence of blood parasites in May (10%), followed by June (9.37%) and July (8.33%). The results showed that male dogs more likely to be infected than females. The incidence of blood parasites in was higher than in female dogs. Males were infected at a rate of 9.23%, while females were infected at a rate of 8.57%.The results of this study showed that the prevalence of <i>D. immitis</i> and <i>D. Reconditum</i> in guard dogs in Tabriz, Iran was 7% and 2%, respectively. Guard dogs should be kept in a sanitary environment and regularly tested for blood parasites. To prevent the growth of blood parasites and their dangerous consequences, they should be regularly treated with anti-parasitic drugs.