Page 1391 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

1366 CHAPTER 14

VetBooks.ir 14.31 Fig. 14.31 Laterolateral radiograph
of a foal with severe abscessing
bronchopneumonia.

Fig. 14.32 Transthoracic ultrasonogram
of the thorax of a foal with aspiration
pneumonia, showing focal consolidated
parenchyma.

14.32 of the equine airway, coughing is a poor indicator
of the presence and severity of respiratory disease.
Similarly, although it is important to perform aus-
cultation of the chest, its findings often do not cor-
relate well with the severity of disease.

Diagnosis
Histories of the individual and group respiratory dis-
ease on the premises, plus clinical examination find-
ings, provide useful information. A thorough physical
examination should be performed. Foals, in particu-
lar young ones, have louder and harsher normal lung
sounds than adults. Clinical pathology, including hae-
matology, inflammatory markers and bacteriological
and cytological examination of a tracheal aspirate,
is required to confirm the diagnosis. Typically, foals
will have leucocytosis, neutrophilia, increased SAA,
increased fibrinogen concentrations and, in chronic
cases, some degree of anaemia. Tracheobronchial
Clinical presentation cytology will confirm an infectious bronchopneumo-
There is considerable variation in the range and nia. Culture and sensitivity are useful in the selection
severity of clinical signs, but they are likely to of appropriate antibiotic therapy. Some agents are dif-
include: tachypnoea (resting rate >25 breaths/ ficult to culture, and false-negative bacterial culture
minute); abnormal respiratory pattern and effort; results are quite common. Definitive diagnosis of
cough (often heard when the foal is being turned R. equi is best achieved by performing tracheal wash
out); pyrexia; nasal discharge; depression, lethargy, PCR for the VapA gene, but cytology and culture of
anorexia and poor growth rate; and progression to the same sample can also be useful. Thoracic radi-
respiratory distress. Nasal discharge is rarely a fea- ography and ultrasonography are useful in assessing
ture of R. equi bronchopneumonia. the degree of involvement and type of the particular
It is important to note that some foals may not disease, its severity and its progression (Fig. 14.31).
exhibit clinical signs of respiratory disease until it is Thoracic radiographs in foals are achievable with
quite advanced. Owing to the relative insensitivity mobile machines. Ultrasonography of the chest is