We received our FIRST tick submission for NETS last week!
It’s always great to see a study start gaining some traction!
Our first tick submitted was a Spinose Ear Tick (Otobius megnini), and true to it’s name, it was both spiny and found in the ear of a horse from Texas! In the picture above, you can see the mouthparts sticking out between the first pair of legs. When these ticks have not fully fed, they have a little waistline that makes their body look like a skeleton head covered in tiny spines! Perfect timing for those still trying to decide on a Halloween costume!
Spinose Ear Ticks are “soft” ticks that parasitize a variety of hosts including horses, cattle, dogs, and even humans. They are commonly found in the western half of the US, and most commonly infest the ear or ear canal. These ticks are unique in that the juvenile stages are parasitic, while the adults are non-parasitic and are free-living on pastures.
There are no known pathogens transmitted by O. megnini to horses, but there are a variety of clinical manifestations reported with Otobius infestations. Horses are often very irritated by tick attachment in the ear canal and may even require sedation prior to rick removal. Horses may express a wide variety of behaviors such as head tilt, head twitching, head throwing, pawing, backing up, or reluctance to move forward. None of these conditions are truly neurologic, but can be misconstrued as a neurologic signs. Muscle twitching and muscle tremors have also been reported with O. megnini infestations, although the physiologic mechanism for those signs is currently not known. https://www.ncbi.nlm.nih.gov/pubmed/7601699
Overall, this tick is mainly considered a nuisance that can create abnormal behavioral signs, which may be incorrectly interpreted as signs of colic or neurologic disease.