Host feeding behaviour of Dermacentor reticulatus males in relation to the transmission of pathogens.

Abstract

The three-host Dermacentor reticulatus tick transmits many pathogens, which are introduced into the host with saliva during feeding. The aim of present study was to analyse the behaviour of males of this species on the host in homogeneous sex groups comprising 15 (group I) and 30 (group II) male specimens and in a mixed group composed of 15 males and 15 females (group III). Although the dynamics of attachment of the males to host skin slightly differed between these three groups, there was no statistically significant difference in the duration of the attachment process. The duration of host attachment of the males in groups I, II, and III at 18±2°C and 50 ± 2% RH was 2.43 ± 2.46, 7.75 ± 11.85, and 9.07 ± 10.97 days, respectively. After 7-9-day feeding, the male engorgement weight (MEW) was similar, regardless of the size of the group and the presence or absence of females on the host. Tick males ingest a small amount of host blood. The value of MEW in the three groups did not differ statistically from the weight of unengorged specimens. The host feeding behaviour of D. reticulatus males and their effective feeding suggest that they may play a role in transmission of pathogens and non-pathogenic microorganisms with tick saliva during blood meal ingestion. Clinical and laboratory diagnostics of human and animal tick-borne diseases as well as epidemiological studies should consider the possibility of pathogen transmission by males of metastriata ticks, which feed on the host for several days.