Chronic Edema Associated with Cor Pulmonale in Cattle

Area of Science:

• Veterinary Pathology
• Cardiovascular Disease in Animals
• Toxicology

Background:

• A chronic, debilitating cattle disease characterized by subcutaneous edema has persisted for 30 years in Bahia, Brazil.
• The etiology and pathogenesis of this disease have remained unknown, impacting cattle health and productivity.

Purpose of the Study:

• To investigate the etiopathogenesis, epidemiology, clinical signs, and pathology of a chronic cattle disease in Bahia.
• To identify the underlying cause of severe edema and right heart failure in affected cattle.

Main Methods:

• Field investigation of 15 disease outbreaks from October 2023 to April 2025.
• Clinical and pathological examination of affected cattle, including histopathology of arterial tissues.
• Analysis of epidemiological data and pasture inspections.

Main Results:

• The disease presents with chronic subcutaneous edema, hydropericardium, hydrothorax, ascites, and right ventricular dilation.
• Histopathology revealed significant arterial wall hypertrophy and hyperplasia, indicative of pulmonary arterial hypertension.
• Affected cattle exhibited significantly thicker pulmonary and heart arteries compared to controls.

Conclusions:

• The disease is characterized as chronic cor pulmonale (right heart failure) secondary to pulmonary arterial hypertension.
• Epidemiological findings and pasture assessments strongly suggest a toxic plant etiology.
• Further research is warranted to identify the specific toxic plant responsible for this cattle disease.