Objective—To determine whether results of physical
or radiographic examination or biochemical analyses
in adult racehorses with primary lung abscesses were
associated with ability to race following treatment.
Design—Multiple-center retrospective study.
Animals—25 Standardbreds and 20 Thoroughbreds.
Procedure—Medical records of horses with a primary
lung abscess that were admitted to any of 4 veterinary
teaching hospitals were reviewed. Results of
physical examination, laboratory testing, and thoracic
radiography were reviewed. Racing performance after
treatment was compared with performance before illness
and with performance of the general population
of racehorses of similar age, sex, and breed.
Results—23 of 25 Standardbreds and 13 of 20
Thoroughbreds raced after diagnosis and treatment of
a lung abscess. Most horses had a solitary abscess in
the dorsal to caudodorsal lung fields. Results of initial
physical examination, biochemical analyses, and culture
and identification of the microbial isolate were
not associated with whether a horse returned to racing.
For horses that had raced prior to the illness, race
performance after treatment of the lung abscess was
not significantly different from performance before
Conclusions and Clinical Relevance—On the basis
of racing performance in those horses that resumed
racing after treatment, long-term residual lung damage
did not develop in horses with primary lung
abscesses that were treated appropriately. It is not
known whether horses that recovered would be more
likely to bleed from the site of a prior infection when
resuming strenuous exercise and whether lung
abscesses contributed to a failure to resume racing.
(J Am Vet Med Assoc 2000;216:1282–1287)