Clinical Cases of Tick-Borne Diseases in Dogs During the Autumn-Winter Season in Poland

Tick-borne diseases (TBDs) pose a growing threat to companion animals, especially dogs, due to the increasing abundance of tick populations in Europe, driven by climate change, urbanization, and the mobility of humans and animals. This study aimed to assess the prevalence of tick-borne pathogens in clinically ill dogs suspected of having developed TBDs during the autumn-winter season, as well as to detect pathogens in ticks collected during the same period in the Warmian-Masurian Voivodeship in Poland. A total of 30 dogs with clinical symptoms of babesiosis and 45 ticks from dogs were acquired for this study. Clinical symptoms in dogs included elevated body temperature > 39.0 °C (73.3%), anemia (56.7%), thrombocytopenia (80%), and dark urine (53.3%). Co-infections with <i>Babesia</i> spp. were identified in two combinations (<i>Babesia</i> spp. and <i>Mycoplasma</i> spp. (<i>n</i> = 5), <i>Babesia</i> spp. and <i>Borrelia</i> spp. (<i>n</i> = 2)) and one co-infection with <i>Anaplasma</i> spp. and <i>Borrelia</i> spp., highlighting the complexity of TBD diagnosis and treatment. The analyzed tick species were <i>Ixodes ricinus</i> (86.7%; <i>n</i> = 39; 18 females and 21 males) and <i>Dermacentor reticulatus</i> (13.3%; <i>n</i> = 6; 4 females and 2 males). In <i>I. ricinus</i>, <i>Babesia</i> spp. were identified in 7.7% (3/39), <i>Mycoplasma</i> spp. in 7.7% (3/39), <i>Borrelia</i> in 25.6% (10/39), and <i>Anaplasma</i> spp. in 10.3% (4/39). In <i>D</i><b>.</b><i>reticulatus</i>, only two pathogens-<i>Borrelia</i> spp. and <i>Anaplasma</i> spp.-were detected, both only once (16.7%; 1/6). No significant differences were observed between the prevalence of the studied pathogens and tick species, sex, or developmental stage. This study emphasizes the year-round risk of TBDs in dogs, particularly during the autumn-winter months, and underscores the need for continuous vigilance in tick prevention, broad-spectrum diagnostics, and treatment strategies.