Mulberry Heart Disease

Introduction

This is a nutritional disease affecting the myocardium of pigs, causing sudden death in young pigs in good body condition. The cause is unknown but is thought to be due to a Vitamin E/Selenium deficiancy in these animals. This would cause a lack of free radical scavenging, which would therefore allow haemorrhage into the myocardium. Death is due to an acute congestive heart failure.

Signalment

Young pigs around 3 -4 months of age are most at risk. They are normally in good body condition. There is no sex or breed predilection.

Clinical Signs

The only clinical sign is sudden death.

Pathology

Grossly, one will see excess pleural fluid in the thorax, which will clot on exposure to air. The pericardium will be oedematous and contain some fibrous clots. There will be haemorrhage on the epicardial surface which my extend into the myocardium, particularly in the right atrium and ventricle. There will also be excess fluid in the peritoneal cavity and the intestinal serosa and liver will appear congested. The will be oedema in the gall bladder and skeletal musculature.
Mircoscopically, there will be haemorrhage in the heart followed by foci of myocardial necrosis. Characteristic linear and ecchymotic haemorrages are seen under the visceral pericarium and haermorrhage extends between the fibres.

Diagnosis

Diagnosis is based on history and sudden death, plus necropsy findings.

Treatment and Control

There is no treatment for this condition, but control measures include ensuring there is enough vitamin E in the the diet of pigs.

References

Jackson, G.G. and Cockcroft, P.D. (2007) Handbook of Pig Medicine, Saunders Elsevier.
Smyth, B (2008) Cardiovascular System Study Guide, Royal Veterinary College.
Straw, B.E. and Taylor, D.J. (2006) Disease of Swine, Wiley-Blackwell.
Taylor, D.J. (2006) Pig Diseases (Eighth edition), St Edmunsdbury Press ltd.