Discussion
The present study has provided information about the
prevalence of colic in a population of UK horses that
display crib-biting / windsucking behaviour. In addition,
we have identified a number of horse- and management-
level risk factors that are associated with increased
likelihood of a history of colic in horses that display
these forms of stereotypic behaviour.
The prevalence of colic within a UK population horses
that display crib-biting/windsucking behaviour appeared
to be high (38 colic episodes per 100 HYAR for all colic
episodes and 20 veterinary attended episodes of colic per
100 HYAR), and a proportion of these horses were
reported to have had multiple recurrences of colic.
Within the general (managed) equine population, the
prevalence of colic in published studies varies from 3.5-
10.6 colic episodes per 100 horses per year (i.e. per 100 HYAR) [23-26] which is lower than the present study. It
is important to note that, because these populations may
differ from those investigated in the present study (e.g.
geography and population demographics), and because
this study did not measure prevalence of colic in a similar
population of horses that did not display crib-biting/
windsucking behaviour, direct comparisons between
these studies cannot be reliably made. In a study investigating
risk factors for epiploic foramen entrapment colic
in the UK [16] in a similar, predominantly pleasure horse
population, of 522 randomly selected control horses (i.e.
non-EFE horses randomly selected from the same population),
41 horses (7.8%) were reported to have had one
or more episodes of colic (veterinary and non-veterinary
attended) in the 12 months prior to the questionnaire
being administered. A total of 80 colic episodes were
reported, equating to 15.3 episodes of colic per 100
HYAR (previously unpublished data), which is again less
than the prevalence found in the present study. The
apparent high prevalence of colic in the present study is
in agreement with a study conducted by Malamed et al.
[11] who reported that horses that had a history of cribbiting
or windsucking behaviour were twice as likely to
have a history of previous colic compared to those that
did not display these stereotypies. However, the latter
study was undertaken in a population of horses referred
to an equine clinic which may reflect a biased population.
Recurrence of colic was also common in a sub-group of
these horses in the present study. This is in agreement
with the findings of Scantlebury et al. [13] who found
that horses that displayed crib-biting/windsucking behaviour
were 12 times more likely to have a history of
recurrent colic compared to horses that did not display
these behaviours. Most colic episodes reported in the
present study were medical in nature and very few of
these episodes necessitated surgical intervention (1.9%).
We do not suggest that crib-biting/windsucking behaviour
causes colic, and the majority of horses in the present
study had no prior history of colic. However, it is
possible that a sub-population of horses that display cribbiting/
windsucking behaviour exists that may have some
inherent difference in intestinal function that is associated
(potentially causally with respect to colic) with
both CBWS and colic.