Equine Viral Diseases Overview

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Questions and Answers

What is the primary cause of Equine Viral Rhinopneumonitis?

Equine influenza virus

Equine herpes virus (EHV-1 and EHV-4) (correct)

Adenovirus

Bovine Respiratory Syncytial Virus

Equine Influenza is a disease with high mortality rates in horses.

False

What is the result of Rhodococcus equi infection in foals?

Granulomatous pneumonia

The primary bacterial cause of Shipping Fever in cattle is __________.

Mannheimia haemolytica Signup and view all the answers

Match the following equine diseases with their causes:

Equine Viral Rhinopneumonitis = Equine herpes virus (EHV-1 and EHV-4) Equine Influenza = Influenza A virus Rhodeococcus pneumonia = Rhodococcus equi Equine Viral Arteritis = Equine arteritis virus Signup and view all the answers

Which of the following diseases in cattle is also known as contagious bovine pleuropneumonia?

Contagious bovine pleuropneumonia Signup and view all the answers

Secondary bacterial infections are common in cases of Equine Influenza.

True Signup and view all the answers

Which of the following is a viral disease affecting sheep?

Peste Des Petits Ruminants Signup and view all the answers

Canine distemper is a highly contagious disease primarily affecting older dogs.

False Signup and view all the answers

What is characterized by the accumulation of chylous fluid in the thoracic cavity?

Chylothorax Signup and view all the answers

The bacteria responsible for caseous lymphadenitis in sheep are called _____________.

Corynebacterium pseudotuberculosis Signup and view all the answers

Match the disease with its corresponding characteristic:

Pleuritis = Inflammation of the pleura Pneumothorax = Accumulation of gas in the thoracic cavity Pyothorax = Accumulation of pus in the thoracic cavity Hemothorax = Hemorrhage within the thoracic cavity Signup and view all the answers

Which of the following is caused by Mycobacterium bovis?

Tuberculosis Signup and view all the answers

Enzootic Pneumonia is solely caused by viral infections.

False Signup and view all the answers

What are the common gross findings observed in tuberculosis?

Firm, yellow-white nodules in the lung and caseous nodules in lymph nodes. Signup and view all the answers

Mycoplasma bovis can cause infections in the lungs, joints, ears, and __________.

mammary glands Signup and view all the answers

Match the Mycobacterium species to their primary host:

Mycobacterium bovis = Cattle Mycobacterium tuberculosis = Humans Mycobacterium avium = Poultry Signup and view all the answers

What type of necrosis is primarily observed in Mycoplasma bovis infections?

Caseous necrosis Signup and view all the answers

Stressful conditions can predispose calves to enzootic pneumonia.

True Signup and view all the answers

What is the pathogenesis of tuberculosis starting with the inhalation of aerosol droplets?

Inhalation of droplets leads to phagocytosis by alveolar macrophages, followed by intracellular replication, macrophage death, and caseous necrosis. Signup and view all the answers

Granulomas in tuberculosis consist of caseous necrosis surrounded by __________ and giant cells.

macrophages Signup and view all the answers

Which of the following environmental factors does NOT predispose calves to enzootic pneumonia?

Excess sunlight Signup and view all the answers

Study Notes

Horse

Equine Viral Rhinopneumonitis is an acute respiratory disease in foals (4-8 months) caused by Equine herpes virus (EHV-1 and EHV-4).
- The virus manifests in three forms: Abortion (pregnant mare), Respiratory, and Nervous.
- Respiratory form causes bronchointerstitial pneumonia with non-collapsing lung lobes and rib impressions.
- Neurologic form causes vasculitis, ischemia, and myeloencephalopathy.
- Aborted fetuses show multifocal areas of necrosis in various organs (liver, lung).
Equine Influenza is a highly contagious respiratory disease caused by Influenza A virus (Orthomyxovirus).
- It has high morbidity and low mortality, often resulting in mild symptoms.
- Secondary bacterial infections (Streptococcus equi) can occur.
Equine viral arteritis is caused by equine arteritis virus (EAV).
- It affects mainly horses.
- It causes systemic vascular inflammation affecting numerous organs.
Rhodococcus equi causes granulomatous disease in foals, also known as Rhodococcal pneumonia.
- It forms multiple, firm nodules containing caseous necrosis and can cause pyogranulomatous lymphadenitis in the bronchial and mesenteric lymph nodes.
- Microscopically, Rhodococcal pneumonia presents with pyogranulomatous pneumonia (granuloma contains neutrophils).
- Burkholderia mallei is the causative agent of glanders in horses.

Cattle

Infectious Bovine Rhinotracheitis (IBR) is a respiratory infection in cattle.
- Caused by bovine herpes virus-1 (BHV-1).
- The virus causes inflammation of the nose, trachea, and lungs.
Bovine Respiratory Syncytial Virus (BRSV) is a common cause of respiratory disease in calves.
Parainfluenza-3 virus is another viral agent implicated in bovine respiratory disease.
Bovine viral diarrhea virus (BVDV) is known to cause respiratory symptoms as well as immunosuppression.
Bovine coronavirus also causes respiratory disease in cattle.
Mannheimia haemolytica (previously Pasteurella haemolytica) is a major bacterial agent responsible for shipping fever, an acute respiratory disease in cattle that occurs after shipment.
- Shipping fever is characterized by fibrinous bronchopneumonia, which presents as:
  - Cranioventral hepatization (red and firm lung tissue)
  - Covered with yellow fibrin sheets
  - Hydrothorax (fluid in chest cavity)
  - Marbling and mosaic appearance due to multifocal necrosis and interstitial edema.
Pasteurella multocida is another bacterial agent implicated in bovine respiratory disease.
Hemophilus somnus is a bacterial species associated with pneumonia and other diseases in cattle.
Actinobacillus pyogenes can also cause pneumonia in cattle.
Mycoplasma mycoides ssp. mycoides is a bacterium responsible for Contagious bovine pleuropneumonia, a severe respiratory disease in cattle.
- Causes fibrinous bronchopneumonia similar to shipping fever.
Mycoplasma bovis is a bacterial species associated with pneumonia, arthritis, otitis, and mastitis in cattle.
- It causes multifocal nodules containing caseous necrosis, visible grossly.
- Microscopically, it presents with multifocal areas of caseous necrosis surrounded by neutrophils.
Enzootic Pneumonia of calves is a multifactorial disease in young cattle, predisposed by environmental factors (temperature, humidity, poor air circulation, crowding) and additional stressors (immune status, viral infections).
- Bacterial agents such as Mycoplasma bovis, Mannheimia haemolytica, and Pasteurella multocida are implicated in its development.
Tuberculosis in cattle is a zoonotic granulomatous bacterial disease caused by:
- Mycobacterium bovis (cattle)
- Mycobacterium tuberculosis (human)
- Mycobacterium avium (poultry)
- It can be transmitted through inhalation of aerosol droplets or ingestion of contaminated material.
- Pathogenesis: Bacteria are phagocytized by alveolar macrophages, where they replicate intracellularly due to their resistance to lysosomal hydrolases.
- Gross Findings:
  - Lung: firm, yellow-white nodules (tubercles) with encapsulation, caseation (cheese-like appearance), and calcification.
  - Multifocal tubercles on the pleura (pearl disease).
  - Caseous nodules in tracheobronchial lymph nodes.
  - Multifocal nodules on various organs (liver, kidney, intestine, CNS, vertebrae) (Miliary TB).
- Microscopic Findings: Granulomas formation with central areas of caseous necrosis and calcification surrounded by macrophages, lymphocytes, plasma cells, and Langhans giant cells.
- Diagnostic tests: Tuberculin test, PCR, special stains (Ziehl-Nielson), and culture

Sheep and Goats

Ovine Adenovirus is a viral agent associated with respiratory disease in sheep.
Respiratory Syncytial Virus also affects sheep, causing respiratory infections.
Lymphoid Interstitial Pneumonia (Maedi) is a chronic, progressive respiratory disease in sheep caused by a lentivirus.
Caprine Arthritis Encephalitis (CAE) is a lentiviral disease affecting goats, resulting in arthritis, encephalitis, and respiratory disease.
Peste Des Petits Ruminants (PPR) is a viral disease affecting sheep and goats, characterized by respiratory symptoms, diarrhea, and skin lesions.
Sheep pox is a viral disease that affects sheep and causes skin lesions and respiratory symptoms.
Mannheimia haemolytica, Pasteurella multocida, and Hemophilus somnus are bacterial species responsible for respiratory diseases in sheep and goats.
Mycoplasma spp. are also implicated in respiratory infections in sheep and goats.
Caseous lymphadenitis is a bacterial disease caused by Corynebacterium pseudotuberculosis, affecting mainly sheep and goats.
Muellerius capillaris is a parasitic lungworm affecting sheep and goats, causing characteristic subpleural nodules in the dorsal region of the caudal lung lobes.
Hydatid cyst is the intermediate stage of Echinococcus granulosus (tapeworm) affecting sheep and goats.

Dog

Canine Influenza is a contagious respiratory disease in dogs.
Canine adenovirus is a group of viruses that can cause upper respiratory infections in dogs.
Canine distemper is a highly contagious viral disease in young dogs caused by Morbillivirus (paramyxoviridae).
- It causes multisystemic disease: Conjunctivitis, Rhinitis, Bronchointerstitial pneumonia, Enteritis, Parakeratosis (Paws), and Encephalitis.
Canine herpesvirus is a virus that can cause respiratory and other infections in dogs.

Cat

Feline Calicivirus causes upper respiratory infections in cats.
Feline Rhinotracheitis is a respiratory infection caused by Feline Herpes Virus-I (FHV-I), resulting in rhinitis and tracheitis in cats.
Feline Infectious Peritonitis (FIP) is a fatal viral disease caused by Feline Coronavirus (FCoV). It causes inflammation of the peritoneum, pleura, and other organs.

Pleura

Pleuritis (Pleurecy) is inflammation of the pleura, resulting in abnormal contents within the pleural cavity.
Pneumothorax is characterized by the accumulation of gases within the thoracic cavity.
Hemothorax refers to hemorrhage within the thoracic cavity.
Chylothorax is the accumulation of chylous fluid (lymph) in the thoracic cavity.
Hydrothorax is the accumulation of clear fluid within the thoracic cavity.
Pyothorax is the accumulation of pus within the thoracic cavity.

Lung and Pleural Tumors

Lung and pleural tumors are relatively rare in animals compared to humans but more common in dogs and cats. Metastatic sarcoma is a possibility.
According to cell line:
- Epithelial tumors include adenoma or carcinoma.
- Mesenchymal tumors include sarcoma and fibromas.

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Description

This quiz covers various equine viral diseases including Equine Viral Rhinopneumonitis, Equine Influenza, and Equine Viral Arteritis. It explores the causes, symptoms, and effects of these viral infections on horses, particularly in young foals. Participants will test their knowledge on the clinical manifestations and complications associated with these diseases.