Ticks (Acari: Ixodidae) infesting cattle and some other domestic and wild hosts on the French Mediterranean island of Corsica

Abstract

Background: Corsica is a mountainous French island in the north-western Mediterranean presenting a large diversity of natural environments where many interactions between domestic animals and wild fauna occur. Despite a favourable context for ticks and tick-borne diseases (TBDs), the tick fauna of Corsica has not systematically been investigated. Methods: For one year (May 2014-May 2015), a survey of ticks infesting cattle was performed in the three Corsican cattle slaughterhouses. Two of these were visited monthly and one quarterly; the ticks were manually collected, just after flaying. Ticks were identified on their morphology; when necessary, some specimens were also molecularly identified by sequencing mitochondrial cox1 (cytochrome c oxidase subunit 1) and 16S ribosomal RNA genes and ITS2 (internal transcribed spacer 2). During the same period, ticks from other domestic animals (small ruminants, horses, domestic carnivores) and wild animals (wild boars, mouflons, deer) were occasionally collected. Results: A total of 1,938 ticks was collected from 264 of 418 cattle examined, reared in 86 different localities. Eight tick species were found infesting cattle: Rhipicephalus bursa (56.1 %), Hyalomma marginatum (21.5 %), Hy. scupense (8.7 %), Ixodes ricinus (5.7 %), Haemaphysalis punctata (4.8 %), Rh. sanguineus (sensu lato) (2.3 %), Rh. (Boophilus) annulatus (0.7 %) and Dermacentor marginatus (0.2 %). The cattle infestation rate remained high all year (more than 50 %). Several tick species showed seasonal variation of their activity. From other Corsican animals 1,196 ticks were collected. Comparing ticks collected from cattle with those found on other animals, several host preferences were shown. A noteworthy record is that of a few Ha. sulcata on mouflons which were mainly infested by Rh. bursa. Conclusion: The Corsican tick fauna is characterized by typical Mediterranean species (Rh. bursa and Hy. marginatum), but the mild climate and diversified environment provide satisfactory habitats both for species usually found in dry areas (Hy. scupense) and species usually collected in humid areas (I. ricinus).