Cardiovascular disease in farm animals

Question 1

You are presented with a non-pregnant beef cow with 1.5/5 BCS, submandibular oedema and ascites. What could be causing the ascites?

Answer 1

Ascites is a consequence of either:

• Right-sided heart failure e.g. caused by endocarditis, pericarditis, dilated cardiomyopathy, chronic respiratory disease, mediastinal mass.
• Hypoproteinaemia (hypoalbminaemia): e.g. caused by chronic fasciolosis, pyelonephritis, paratuberculosis.

Question 2

True/false: if a cow has endocarditis or dilated cardiomyopathy, it will have an audible murmur.

Answer 2

False.

There may be no audible murmur with these conditions.

Question 3

7 y.o. Holstein cow presents with 2 week history:

• Poor milk yield
• Reduced appetite
• Marked loss
• She is dull, stands with a roached back and abducted elbows. She has a painful expression.
• She has marked jugular distension
• HR: irregular, 96 bpm, no audible murmurs.
• RR: 36 breaths/min
• Temp 39.1⁰C

Differentials (most likely first)?

Answer 3

• Bacterial endocarditis
• Chronic suppurative pulmonary disease
• Pleural effusion/abscess
• Traumatic reticuloperitonitis
• Septic pericarditis
• Myocarditis

Question 4

This cow showed weight loss, jugular distention, elevated heart and respiratory rate and abnormal posture. What findings are present on her heart at necropsy?

Answer 4

This is a large vegetative lesion on the tricuspid valve.

Question 5

What changes to the heart might you detect on clinical exam of a cow suffering endocarditis?

Answer 5

• Increased and irregular heart rate (>100bpm)
• Normal heart sounds without an audible murmur

Question 6

This is an image of a cow’s heart at necropsy. What diagnosis will you make?

Answer 6

Septic pericarditis

Question 7

This cow is now dead. Based on these necropsy findings, could/should she have been saved? Why/why not?

Answer 7

• Septic peritonitis
• Correct course of action: euthanasia for welfare reasons
• Even if surgery to remove the pericardium was financially viable, it would not have been successful, due to the large amounts of fibrin deposited on the epicardium.

Question 8

Could this situation have been prevented?

Answer 8

Septic peritonitis may have occurred due to traumatic reticulitis → penetration of pericardium by sharp metal object.

Prompt detection of traumatic reticulitis cases sometimes (but not always) permits removal of the wire.

In herds with a history of hardware disease, routine bolus of magnets can be performed.