What is ailing the reindeer?
A blood sample from a 3.5-year-old female reindeer slightly underweight was submitted for a CBC and a modified Knott’s tests.
Image 1-3: Modified Knott's test.
Image 4: Microfilariae are 140-169 µM in length with a blunt rounded tail and a sheath closely pressed against the body of the microfilariae extends only a short distance beyond the head and tail which makes it difficult to see
Rumenfilaria andersoni, is a filarid nematode (Family Onchocercidae, subfamily Splendidofilariinae). It was firs described from moose (Alces alces) in Ontario, Canada and mistakenly to occur in subserosal veins of the rumen. Adult worms are 55-144 µM in length. In addition to moose, infections have also been reported in reindeer (Rangifer tarandus), white tail deer (Odocoileus virginianus) and roe deer (Capreolus capreolus). Infection in cervids have been reported in Alaska, Ontario and Finland. It may have been introduced into Finland in imported white-tailed deer from Minnesota donated by Finnish immigrants.
Case and photos provided by Dr. Gary Conboy.
Winter is coming....
In November 2020, these ticks were removed from a horse in Oklahoma and submitted to the parasitology lab for identification.
Images 1-3: Key features for identification.
These ticks are a brown variant of Dermacentor albipictus, or the winter tick, a one-host tick commonly found on horses and white-tailed deer in the southern region of North America. Formerly referred to as D. nigrolineatus, inornate winter ticks can be distinguished from Rhipicephalus spp. by the presence of a rectangular scutum. The ornate variant of D. albipictus more common in northern regions is often found feeding on moose, elk, and deer. In large numbers, D. albipictus contribute to poor condition and death in moose and elk. Winter ticks, as the name suggests, are most active in the fall and winter months, and have been implicated as vectors of Anaplasma marginale and Babesia duncani.
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