Seasonal Dynamics and Physiological Age of Ixodid Ticks Collected from Dogs

Simple Summary A large number of dog owners are informed about ticks and tick-borne diseases that could be dangerous for their pets. However, they are not familiar with tick biology, seasonal activity, and the possibility that some pathogens could be transmitted from dogs to humans. The aims of this study were to determine tick species and their seasonal occurrence on pet dogs and to compare the accuracy of three indices frequently used to calculate tick female physiological age in terms of feeding process duration. As a result of a one-year study, four tick species were identified and their seasonal patterns showed a continuous occurrence on dogs through the whole year, even during the winter months. The most accurate index was the physiological age index, the only tested index which included body mass as a variable measure. Seasonal activity of ticks depends on numerous factors: abiotic, biotic, and anthropogenic. Tick species diversity and abundance in specific geographical range varied in recent years, due to global climate changes and increase of human and animal migrations. These topics demand the One Health approach, where the integrated efforts of scientists, veterinarians, and physicians are essential in order to prevent and manage tick-borne pathogens and diseases.Abstract In order to reproduce and complete life cycles, ticks have to feed on different hosts, thus participating as vectors and reservoirs in the maintenance and circulation of different pathogens. Since dogs can serve as suitable hosts for numerous tick species, the aims of this study were to determine tick species and their seasonal occurrence on pet dogs and to compare the accuracy of three indices frequently used to calculate engorged female physiological age. Ticks were collected from dogs brought to veterinary clinics. Three indices were analyzed: scutal index, alloscutal/scutal index ratio, and physiological age index. Four tick species were identified: Ixodes ricinus, Dermacentor marginatus, D. reticulatus, and Rhipicephalus sanguineus group, and the last was the most abundant. The highest number of collected ticks was in April, but two species were continuously active throughout the year. The statistical analyses distinguished the physiological age index as more precise because of lower variability. Dog owners usually ignore regular dog anti-tick treatments throughout the year, as they are not aware that ticks could be active during the winter months. Tick surveillance is unquestionably important in order to monitor and prevent the distribution of these vectors and also the diseases they transmit.