Frequency of Ticks and TBDs of Horses
Veterinarians were asked to rank concern regarding specific TBD
conditions on a Likert scale, with 1 being the most concerning and 6
being the least concerning. Veterinarians were primarily concerned with
Lyme disease and anaplasmosis (mean = 2.0 for each, respectively). There
were no differences among regions for either tick-borne disease. There
was less concern for piroplasmosis (mean = 4.0) and tick-associated skin
conditions (mean = 3.0). There was a trend towards a higher concern of
piroplasmosis in the northeastern states, but it was not statistically
significant. There was less concern for tick-borne skin conditions in
the Northeast than in other regions of the United States (P=0.016).
Overall, most equine veterinarians removed three or more ticks from
horses per year (81.7%, 49/60; Table 4) and only 5% (3/60) of
veterinarians never removed a tick, although the “0 tick” response was
exclusively from the Midwest region. Nearly 70% (15/22) of
veterinarians removed six or more ticks in the Northeast region. This
was significantly more than the combined responses of the remaining
regions (Mann-Whitney U; P=0.030), where most veterinarians reported
removing less than five ticks per year. However, the frequency of body
checks for ticks did not differ between the Northeast and the combined
responses from the remaining regions. Seventy-five percent (42/56) of
responding veterinarians removed ticks from horses, and 51.8% (29/56)
of veterinarians responded that clients had brought in ticks that had
been removed from a horse. Interestingly, neither response differed
among U.S. regions.
Equine veterinarians were asked to click on locations on an image
representing an equine body that best represented where ticks were most
frequently removed (Figure 6). Responses from the Northeast and Midwest
were grouped and responses from the Southeast and South-Central were
grouped; this was done to combine regions where tick species presence
and abundance would be similar. Veterinarians in the Northeast and
Midwest most frequently removed ticks from under the jaw, the hind legs,
and by the elbow/between the front legs (Figure 6A). In the Southeast
and South-Central regions (Figure 6B), ticks were commonly collected
from the ears, between and on the front legs, on the flank, between the
hind legs, and on the horse’s sides. In the West region, veterinarians
removed ticks scattered on the ears, crest, under the jaw, limbs, flank,
belly, and between the back legs (Figure 6C).
The frequency of diagnosis of any TBD (anaplasmosis and Lyme disease) in
horses was higher in the Northeast than in other regions of the country
(P=0.001). However, there were no differences in the confidence of
veterinarians to accurately diagnose TBDs based on disease signs, tick
identification, and knowing which tick transmits diseases in the
Northeast versus other regions of the United States. Over 28% (16/57)
of veterinarians responded that they had diagnosed a horse with
tick-borne paralysis, and over 25% (15/59) for piroplasmosis.
Cumulatively, most veterinarians have found a tick on a horse being
treated for a tick-borne disease (75%; 42/56). Finding a tick was more
frequent in the Northeast (90.5% of respondents) compared to other
regions (65.7% of respondents) (P=0.038). Fewer veterinarians reported
clients removed ticks and brought them to the provider (51.8%; 29/56)
and this did not differ among regions. However, most veterinarians
across all regions (73.7%; 42/57) responded that clients ask them for
tick information, and even more veterinarians recommend tick control
(79.7%; 47/59). Overall, veterinarians reported that clients were
willing to spend an average of $141.53 a year on tick control for their
horses, and this did not differ among regions.