Common Cardiovascular Diseases in Farm Animals

Common Cardiovascular Diseases of Production Animals

• This presentation covers common cardiovascular diseases in farm animals.

Learning Objectives

• Students will be able to create a differential diagnosis list for cardiac diseases in common farm animals, based on history & clinical signs.
• Students will identify appropriate medical and surgical interventions for treating cardiac diseases.
• Students will determine the prognosis for cardiac disease in individual animals and in a herd.
• Students will be able to identify suitable prevention and control measures for cardiac diseases in farm animals.

Thorough Case Work Up

• History: Includes animal age, management practices, duration of disease, recent treatments, current management (feeding, housing), stage of lifecycle (lactation, pregnancy), and any changes in management.
• Signalment: Not detailed in the notes but implicitly part of a complete case history.
• Clinical Signs: Includes both acute (e.g., sudden death) and chronic (e.g., reduced production, lethargy) signs. Specific signs listed include edema, pale mucous membranes, increased heart rate, muffled heart sounds, and non-specific signs like reduced milk yield.
• Physical Exam Findings: Covers overall demeanour, temperature, body condition score (BCS), assessment of other body systems (cardiovascular and respiratory), auscultation, jugular fill, and respiratory rate & effort.
• Diagnostics: This section suggests further investigations to arrive at a definitive diagnosis.

History

• Age
• Management details
• Duration of disease
• Progression of disease
• Recent treatments
• Current management practices
• Feeding regime
• Housing conditions
• Lifecycle stage (e.g., lactation, pregnancy)
• Changes in current management

Clinical Signs

• Acute vs. Chronic: Acute presentations have sudden onset, dramatic presentations like oedema and sudden death. Chronic presentations are more subtle with reduced production and lethargy.
• Acute signs: Edema (submandibular/brisket), pale mucous membranes (MM), increased heart rate(HR), muffled heart sounds. Sudden death can be a sign of acute disease
• Chronic signs: Reduced production (milk, growth), lethargy, inappetence.

Physical Examination

• Demeanour: Animal's overall behavior and attitude
• Temperature: Animal body temperature
• BCS: Body condition score (scoring of physical condition)
• Cardiovascular System: Heart rate, rhythm, presence of any murmurs, jugular vein fill, and pulsation.
• Respiratory System: Respiratory rate, effort during breathing, and sounds upon auscultation.

Right Sided Heart Failure

• Characterized by venous return issues leading to elevated venous pressure.
• Symptoms involve edema, ascites, and pleural effusion.

Left Sided Heart Failure

• Characterized by increased atrial pressure from issues with ventricle function and resultant inability to pump blood around the body.
• Symptoms include pulmonary edema, tachycardia, and weak pulses.

Main Causes of Cardiovascular Diseases

• Infectious: Traumatic reticuloperitonitis, endocarditis, erysipelas, and clostridial myositis.
• Congenital: Ventricular septal defect (VSD) and patent ductus arteriosus (PDA).
• Other: Degenerative disease (white muscle disease) and secondary issues like those arising from cor pulmonale.

Cardiac Auscultation

• Arrhythmias, often secondary to other issues like pain, infection. Heart failure/compensation for reduced contractility. Electrolyte disturbances (hypomagnesaemia/hypocalcaemia) are also implicated.
• Bradyarrhythmias: Electrolyte disturbances (hyperkalaemia), white muscle disease, intoxications (e.g., rhododendron).

Murmur Localization:

• Specific areas of the chest are associated with each heart sound, providing clues to the origin of the abnormal heart sounds.

Murmur Differentiating Symptoms

• Indicate whether the abnormal heart sounds are systolic, diastolic, or continuous to help determine the potential causes.
• Murmurs are linked to issues like mitral/tricuspid regurgitation, and ventricular septal defects.

Additional Diagnostics

• Withers Pinch: Identifying potential abdominal pain.
• Glutavac: Measure of fibrinogen/inflammation, and can assist with prognosis.
• Ultrasound: Can detect pericardial effusion useful in assessment.

Differential Diagnoses

• Categorizing potential causes (infectious, congenital, and other) for cardiac diseases.

Traumatic Reticuloperitonitis

• Causative factors include ingestion of foreign bodies penetrating the pericardium, septic peritonitis, fluid accumulation leading to cardiac tamponade and right heart failure.
• Signs include muffled heart sounds, splashing/tinkling heart sounds, and right-sided heart failure.

Traumatic Reticuloperitonitis Treatment, Prevention, and Prognosis

• Treatment strategies include antibiotics, NSAIDs, potentially use of magnets, surgery or culling.
• Prognosis varies widely, and the success of treatment often depends heavily on detection timing.

Vegetative Endocarditis

• Bacterial infection of heart valves which may originate from bacteraemia.
• Affects animals like cattle due to infections such as mastitis, and pigs from issues including erysipelas.

Vegetative Endocarditis (Clinical Signs, Treatment, Prognosis)

• Signs consist of pyrexia, recurrent, waxing/waning, non-specific weight loss/reduced production, and systolic murmurs.
• Treatment requires long-term broad-spectrum antibiotics.
• Prognosis is generally poor, with a short average lifespan after diagnosis.

Pulmonary Thromboembolism

• Spread of clots to the lungs.
• Causes include hepatic abscesses, rumen acidosis, or haematological issues originating from elsewhere in the body.
• Resultant effects often lead to pulmonary artery abscesses or other major respiratory symptoms.

Cor Pulmonale

• Right-sided heart hypertrophy, and heart failure related to issues with the lungs.
• Dairy cattle and holstein's are often involved.
• Secondary to chronic issues like chronic lungworm, or chronic respiratory diseases.

White Muscle Disease

• Results from Selenium and Vitamin E deficiencies.
• Often occurs in young animals with rapid growth, those on poor quality diets or feed sources with insufficient micronutrients, and in herds/flocks sharing similar underlying issues.
• Signs include skeletal weakness(stiffness) and recumbency, cardiac murmurs/irregular tachycardia, and symptoms associated with diaphragm function.