Nine dogs with pyothorax were treated with systemic antibiotics, and draina
ge and lavage of the pleural space. All nine dogs recovered completely. Eig
ht dogs were followed up for 6 months or longer and none showed signs of re
lapse. The results of this treatment are excellent compared with those for
treatment with systemic antibiotics and drainage of the pleural spaced but
without lavage. Apart from the addition of pleural lavage to the treatment
protocol, this difference in efficacy may be due to the fact that migrating
grass seed awns do not seem to play an important role in the pathogenesis
of pythorax in dogs in the Netherlands.