Apparent fatal winter tick () infestation in captive reindeer ().

The winter tick, (Ixodidae), commonly infests a wide variety of wild and domestic ungulates throughout North America. This one-host-tick infests animals from October to April, with moose () particularly affected. Animals highly infested may present with anemia, tick-induced alopecia, and alterations in thermoregulation, often resulting in death Mortality from winter tick infestation has been reported in free-ranging woodland caribou () and captive reindeer in Alberta, Canada. This historic report raises concern about mortality due to in a wider host range, specifically on translocated caribou. The aim of this report was to describe three cases of winter tick infestation in captive reindeer resulting in severe anemia and mortality likely due to the infestation in New Hampshire, northeastern United States (US). Additionally, ticks were screened molecularly for the detection of tick-borne pathogens. At time of necropsy, all three reindeer showed decreased nutritional status, marked submandibular edema, and had heavy infestation. None of the reindeer exhibited alopecia, which is a common clinical manifestation in moose that die from winter tick infestation. No pathogens were detected via qPCR screening. This report highlights the risk that captive cervids face in areas where winter tick is endemic; therefore, the adoption of preventive control measures should be encouraged to reduce the risk of tick infestation and potential death of these animals.