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Respiratory Disease of Adult Cattle
Phil Scott DVM&S, DipECBHM, CertCHP, DSHP, FRCVS
Introduction
Auscultation is considered as a critical component of
the veterinary clinical examination for the diagnosis of
bovine respiratory disease but studies have shown that
a stethoscope detects only around 5 per cent of cattle
with lung consolidation. In bovine respiratory diseases,
modern portable ultrasound machines provide the
veterinary
practitioner
with
an
inexpensive,
non-invasive tool with which to examine the pleural
surfaces and superficial lung parenchyma in less than
five minutes.
Clinical signs
Most cows with chronic suppurative pulmonary disease
have a normal rectal temperature on presentation but
this varies up to 39.2°C. Cattle have an increased
respiratory rate above 40 breaths per minute with an
obvious abdominal component. There is frequent and
productive coughing, halitosis, and a purulent nasal
discharge most noticeable when the head was
lowered.
-
Typically affects first calved heifers
-
Disappointing milk yield
-
Cattle are dull, in poorer condition than their peers
with a dry staring coat,
-
Variable rectal temperature - normal to 39.2°C.
-
Cough and purulent nasal discharge.
-
Respiratory rate is increased above 40 breaths per
minute with an abdominal component to respiration.
-
Cattle may stand with an arched back
Chronic suppurative pulmonary disease develops as a
result of unsuccessful treatment or incomplete recovery
from earlier pneumonia episodes as calves and growing
cattle.
Recrudescence of bacterial infection is most often
associated with calving.
The economic implications of chronic suppurative
pulmonary disease include:
-
Poor lactation yield
-
Weight loss
-
Poor fertility performance
-
Many cows are culled
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-
Endocarditis,
-
Pericarditis
-
Liver abscesses,
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Pyelonephritis
-
Hepatocaval thrombosis
Diagnosis
Cattle with chronic suppurative pulmonary disease
may stand with an arched back with the neck
extended and the head held lowered suggestive of
thoracic pain.
It proves difficult to differentiate increased audibility
of normal breath sounds from wheezes; no crackles
were detected over lung pathology identified
ultrasonographically
in
several
studies.
Ultrasonographic examination has been shown to
accurately define the distribution and nature of lung
pathology in those cows with advanced disease that
have not responded to antibiotic therapy.
Affected animals cough frequently and have a
purulent nasal discharge.
Differential diagnosis
Chronic suppurative pneumonia is a difficult
diagnosis in farm animal practice because the cow
has often been treated by the farmer with
antibiotics. Infectious bovine rhinotracheitis and
lungworm should be considered as well as chronic
bacterial infections that cause poor production and
weight loss such as peritonitis, endocarditis,
pericarditis, liver abscessation, pyelonephritis, and
hepatocaval thrombosis.
The 5 MHz linear probe head (PD scanner) is at the
top of the image; dorsal is to the left. The hypoechoic
area ventrally replacing the hyperechoic (white) linear
echo of the normal lung surface represents
consolidated lung lobule.
Common differential diagnoses include:
-
Infectious bovine rhinotracheitis
-
Lungworm
-
Chronic peritonitis.
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Extended course of procaine penicillin is
effective against this bacterium.
-
Penicillin is time-dependent so a long course of
treatment is necessary. The dose rate need not
be increased.
The probe head is at the top of the image; dorsal is to
the left. The hypoechoic area extending for 8 cm in
the ventral lung field represents consolidated lung. (5
MHz sector scanner).
The probe head is at the top of the image; dorsal is to
the left. The hypoechoic lung transmits sound waves
through the diaphragm to image the liver (ventrally;
to the lower right). The consolidated lung featured
has the sonographic appearance of liver referred to
as "hepatoid". (5 MHz sector scanner).
This antibiotic treatment regimen is consistent with
RUMA recommendations on the responsible use of
antibiotics whereby fluoroquinolones, third and
fourth generation cephalosporins and long acting
macrolides have an important place in the
therapeutic armoury for serious diseases of
humans.
Dairy heifer diagnosed with chronic suppurative
pulmonary disease and treated with daily penicillin
injections (see below). This heifer had shown no
improvement after five consecutive days of
marbofloxacin.
Treatment
Trueperella (formerly Arcanobacterium) pyogenes is
the most common isolate from lung tissue samples
of adult cattle with chronic suppurative pulmonary
disease at necrospy. Treatment with procaine
penicillin for 21-42 consecutive days has resulted in
marked improvement with return to normal appetite
and improvement in body condition in cows where
lesions did not extend more than a combined total
of 35-40 cm above the level of the olecranon when
lesions on both sides of the chest are added
together (see below).
-
Trueperella pyogenes is the most common
isolate from lung lesions.
The same heifer as featured above after 10 days '
treatment with penicillin.
Prevention/Control measures
Prevention of chronic respiratory disease involves
vaccination, and prompt veterinary treatment and
monitoring of pneumonia cases in growing cattle. Copyright ©NADIS 2017
Closely monitor all antibiotic treatments. Maintain
BVD/MD free herd status or vaccinate herd.
Chronic suppurative pulmonary disease caused by
persistent BVD infection.
References/further reading
Scott P.R. (2013) Ultrasonographic findings in adult
cattle with chronic suppurative pneumonia. In
Practice 35, 460-469
Scott P.R. (2013) Clinical presentation, auscultation
recordings, ultrasonographic findings and treatment
response of 12 adult cattle with chronic suppurative
pneumonia.
Irish
veterinary
Journal
10.1186/2046-0481-66-5
66,
5
doi:
Buczinski S, Forté G, Francoz D, Bélanger AM. (2014) Comparison of thoracic auscultation, clinical
score, and ultrasonography as indicators of bovine
respiratory disease in preweaned dairy calves. Vet
Intern Med. 28:234-42. doi: 10.1111/jvim.12251.
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