Seasonal dynamic of ticks infesting cattle (Bos indicus) farms in two provinces in Cambodia.

Cattle tick infestations pose a significant threat to livestock health and productivity worldwide. These parasitic arthropods, feed on blood and may cause various diseases in cattle, such as anaplasmosis, babesiosis, ehrlichiosis, and theileriosis. The objective of this study is to understand the seasonal dynamic and distribution patterns of tick infesting cattle in Cambodia. A longitudinal tick survey was conducted from January to December 2023 in two cattle farms in the Takeo and Kampong Speu provinces. Ticks were collected directly from the animal hosts with fine-tip forceps or specialized tools such as tick twisters, and from the vegetation using a combination of dragging and flagging method. A total of 13,678 ticks were collected from 240 inspected cattle and 11,384 ticks were found from vegetation around the two farms. The most prevalent species was Rhipicephalus microplus complex (60.6%), while R. haemaphysaloides was recorded in small numbers (0.4%). Unidentified species represented 39% of the collected ticks, consisting of immature Rhipicephalus spp. In addition, one adult Rhipicephalus linnaei, 245 immatures of Haemaphysalis spp., and 11,138 larvae of Rhipicephalus spp. were collected using dragging and flagging methods. The results revealed significant seasonal differences in tick population dynamics across both provinces, with 60.24% in Kampong Speu and 57.09% in Takeo during the rainy season, compared to 39.76% and 42.91% during the dry season. Statistical analysis on questing activity showed no significant differences in tick density across different collection sites, times of the day and province. Our findings indicate a very high density of tick-borne pathogen vectors was observed on cattle in the two farms, which a poses potential risk to cattle productivity in Cambodia.