Peripartum heart disease in cows

Area of Science:

• Veterinary Medicine
• Animal Cardiology
• Dairy Science

Background:

• Periparturient dairy cows, especially high-producing Holsteins, are susceptible to metabolic and cardiovascular disorders.
• Previous studies have documented various peripartum complications, but specific cardiac pathologies linked to severe illness require further investigation.

Purpose of the Study:

• To investigate the clinical, electrocardiographic, clinicopathological, and necropsy findings in Holstein dairy cows experiencing severe periparturient illness.
• To identify potential causes and pathological changes associated with this condition, focusing on cardiac abnormalities.

Main Methods:

• Case series involving thirteen Holstein dairy cows with severe periparturient illness.
• Clinical examination, electrocardiography (ECG), serum biochemistry, and post-mortem examination (necropsy) were performed.
• Histopathological analysis of cardiac tissue was conducted.

Main Results:

• All cows exhibited clinical signs including lateral recumbency, moaning, tachycardia, and dyspnea, with a short clinical course (average 2.5 days).
• ECG revealed significant tachycardia, atrial fibrillation, or atrioventricular dissociation.
• Severe hypocalcemia (3.6 +/- 1.3 mg/dl) was a consistent finding.
• Necropsy invariably showed multifocal myocardial necrosis with inflammatory cellular infiltrates and interstitial fibrosis.

Conclusions:

• Severe periparturient illness in high-producing Holstein cows is associated with significant cardiac pathology, including myocardial necrosis and electrophysiological disturbances.
• Hypocalcemia is a prominent feature in affected animals.
• The underlying etiology for the observed myocardial necrosis could not be definitively established in this study, warranting further research.