Identification, seasonal prevalence, and preferred attachment sites of ixodid tick species infesting cattle in four municipalities of the province of Tiaret, northwest Algeria

Abstract

Ixodid ticks are important disease vectors that significantly impact animal health and cause considerable economic losses, particularly in tropical and subtropical countries. The aim of the present study was to determine the identity, seasonal distribution, and preferred attachment sites of adult ixodid tick species of cattle in four municipalities (Aïn El Hadid, Sidi Bakhti, Mechraa Safa, and Sidi Hosni) of the Province of Tiaret (north-west Algeria) between May 2022 and May 2023. A total of 317 cattle were randomly selected and examined for tick infestation; 108 (34.07%; 95% CI 28-39) were found to be infested by one or more species of ticks. The mean intensity of tick infestation was 16.22 ± 18.45 ticks per individual, while the mean abundance was 5.53 ± 13.21 ticks per examined cattle. Overall, 1,752 adult ixodid ticks were collected and identified, including 1,353 males and 399 females. Three genus and nine tick species were identified, including, H. excavatum (43.78%), H. marginatum (20.15%), H. lusitanicum (18.32%), H. scupense (8.73%), R. bursa (7.53%), H. impeltatum (0.74%), R. (Boophilus) annulatus (0.46%), R. sanguineus sensu lato (0.23%), and D. marginatus (0.06%). The highest discrepancy indices (D) were recorded for H. impeltatum (0.98), while the lowest was observed for H. excavatum (0.88). The overall discrepancy (D) values range from 0.88 to 0.98, indicating significant seasonal variability in the aggregation of ixodid ticks. The highest infestation rate recorded was in Ain El Hadid at 100%, followed by Sidi Bakhti at 79.76%, Mechraa Safa at 10.53%, and Sidi Hosni at 9.79%. H. excavatum, H. marginatum, H. lusitanicum, H. scupense, H. impeltatum, R. bursa, and R. (Boophilus) annulatus displayed significant variation across municipalities (p < 0.001). Seasonally, the highest abundance of adult ixodid tick infestations occurred in summer (38.01%), while the lowest was observed in autumn (17.29%). Significant seasonal variations were observed in the abundance of H. excavatum, H. marginatum, H. lusitanicum, and R. bursa (p < 0.001). Tick distribution was highest in zone 5 (95.43%), which includes the sternum, abdomen, udder, scrotum, and inner sides of the hind legs, while the lowest occurrence was in zone 1 (0.06%), which includes the head and ears. H. excavatum and H. lusitanicum showed a significant preference for Zone 5 (p < 0.001). The findings from the current study serve as a foundation for creating effective strategies to control tick populations on cattle in the Tiaret province.

Keywords: Aggregation; Cattle; Ixodid ticks; Preferred attachment sites; Province of tiaret.