The predilection sites of Rhipicephalus (Boophilus) microplus tick larvae and nymphs on cattle

Rhipicephalus (Boophilus) microplus is a one host tick that spreads a pathogen that causes Bovine Babesiosis, which results in high mortality and morbidity in cattle. The United States Department of Agriculture has eradicated the pest throughout most of the United States but currently maintains a permanent quarantine zone near the US-Mexico border. However, infestations occasionally occur in southern Texas counties. Trained inspectors palpate the skin of cattle but are limited by the small size (< 1 mm) of the larvae. Six Bos Taurus cattle were artificially infested with R. microplus larvae and visually inspected for larvae 4-5 days post infestation or nymphs 9-10 days post infestation by a trained Cattle Fever Tick Research Laboratory inspector. The location and life stage of ticks found on each animal were recorded. Following inspection, each animal was euthanized, and its hide was sectioned and frozen for hide examination. The larvae and nymphs were mapped to animal hide sections by visual inspection. A modified KOH dissolution technique was used to dissolve hair follicles and the solution was vacuum filtered to recover all ticks from each hide section. The density and distribution of tick larvae and nymphs were mapped for each hide. A comparison was made between the ticks mapped from live animals by the trained inspector and those recovered by the hair dissolution technique. Results and implications will be discussed.