EQUINE | CPD Article
Duration of disease directly affects prognosis and
the development of complications 5 . Horses with an
anaerobic infection also tend to have poorer survival
rates 3 .
Possible complications directly related to the
pleuropneumonia include: pleural adhesions,
pulmonary necrosis, cranial mediastinal abcessation,
bronchopleural fistula, constrictive pericarditis,
endotoxamia and laminitis 10, 11 . Other sequela that
may arise secondary to treatment and nursing
efforts, include 3 : intra venous catheter associated
thrombophlebitis, cellulitis, pneumothorax and
antimicrobial associated colitis 3 .
Image of extensive lung adhesions in a horse euthanized with
pleuropneumonia
Prevention
Pre-travel prophylactic “cocktails’ are often
administered to horses before long distance travel.
This is questionable practice as pre-travel “once- off”
antibiotic prophylaxis has no effect on LRT secretion
accumulations or bacterial population 4 . However
repeated antibiotic administration, taking drug half-life
40
into account, may assist in reducing pleuropneumonia
incidence 2 . This could be considered for "high risk"
horses travelling long distances. The identification of
a sick animal prior to travel and head position during
long distance travel seem to be more protective 2 . It
is also recommended that an overnight stable rest for
every 12 -16 hours of travel 1 and a mandatory stop
after every 4-6 hours of travel 18 be provided during
long tips. Trucking companies should be further
encouraged to only loosely tie the horse’s heads to
enable a greater freedom of movement 1 and to feed
hay from the floor 1 .
Administration of NSAIDs or corticosteroids prior to
travel should be strictly avoided 18 as this could delay
the onset and detection of pyrexia and therefore the
identification of a sick horse. Naso gastric tube (NGT)
administration of 6-8 liters of water has been strongly
advised prior to travel 1 as this may assist in preventing
dehydration and reduced mucocilliary clearance 1
associated with poor water intake during a long
journey. Early post travel clinical examinations are
advisable 1 to allow identification of affected horses as
soon as possible. As far as possible horses travelling
should be adequately vaccinated against respiratory
viral conditions such as EHV and EI 3 and should be
healthy prior to travel.
Conclusion
History and clinical signs may indicate a diagnosis
of pleuropneumonia. Thoracic ultrasound,
thoracocentesis and TTA sampling are important
diagnostic tests that will allow appropriate broad
spectrum antimicrobial therapy to be selected. Pleural
drainage, analgesics and good nursing are required to
help the horse recover. Timeous and correct treatment
may enable the affected horse to recuperate fully and
return to its intended use successfully.
• Equine Health Update •