Equine Respiratory Diseases Quiz

### Equine Viral Rhinopneumonitis (Equine Herpesvirus)

• Acute respiratory disease in foals (4 - 8 months old)
• Caused by Equine herpes virus (EHV-1 and EHV-4)
• Three forms: Abortion (pregnant mare), Respiratory, and Nervous
• Respiratory form: Bronchointerstitial pneumonia (non-collapsing lung lobes, rib impressions)
• Neurologic form: Vasculitis, Ischemia, Myeloencephalopathy
• Aborted fetuses: Multifocal area of necrosis in various organs (liver, lung)

Equine Influenza (Influenza A Virus)

• Highly contagious respiratory disease in horses
• Caused by Influenza A virus (Orthomyxovirus)
• High morbidity, low mortality (usually mild)
• Secondary bacterial infections (Streptococcus equi) are a concern

Rhodococcal Pneumonia (Rhodococcus equi)

• Granulomatous disease of foals
• Caused by Rhodococcus equi (previously known as Corynebacterium equi)
• Grossly: Multiple, firm, nodules containing caseous necrosis. Pyogranulomatous lymphadenitis (bronchial and mesenteric lymph nodes).
• Microscopically: Pyogranulomatous pneumonia (granuloma contains neutrophils)

Infectious Bovine Rhinotracheitis (IBR)

• Viral Disease in Cattle
• Caused by Bovine Herpesvirus-1
• Causes respiratory disease, abortion, and ocular infections
• Can cause a severe pneumonia in young calves

Bovine Respiratory Syncytial Virus (BRSV)

• Viral disease in Cattle
• Causes respiratory disease, particularly in calves
• Often occurs in conjunction with other respiratory pathogens

Shipping Fever

• Acute respiratory diseases of cattle that occur after shipment (stress)
• Often caused by Mannheimia haemolytica (formerly known as Pasteurella haemolytica)
• Grossly: Fibrinous bronchopneumonia, Cranioventral hepatization (red and firm), Covered with yellow fibrin sheets, Hydrothorax, Marbling and mosaic appearance due to multifocal necrosis and interstitial edema

Contagious Bovine Pleuropneumonia (Mycoplasma mycoides)

• Grossly similar to Shipping fever

Mycoplasma bovis

• Causes bronchopneumonia, arthritis, otitis, and mastitis
• Grossly: Multifocal nodules with caseous necrosis
• Histologically: Multifocal areas of caseous necrosis surrounded by neutrophils

Enzootic Pneumonia of Calves (Multifactorial Disease)

• Predisposed by environmental factors (temperature, humidity, poor air circulation, crowding)
• Stress (immune status, viral infections)
• Bacterial involvement

Tuberculosis (Zoonotic Granulomatous disease)

• Caused by acid-fast bacteria (bacilli): Mycobacterium bovis (cattle), Mycobacterium tuberculosis (human), Mycobacterium avium (poultry)
• Pathogenesis: Inhalation of aerosol droplet or ingestion of infected materials (milk). Bacteria phagocytized by alveolar macrophages. Intracellular replication (bacteria resistant to lysosomal hydrolases). Macrophage death and release of enzymes (caseous necrosis). Localize lymph node. Hematogenous dissemination (bacteremia). Seeding of multiple sites (generalized infection).
• Gross findings：Firm, yellow-white nodules (tubercles) in lung. Cut surface shows encapsulation, caseation, and calcification. Multifocal tubercles on the pleura (pearl disease). Caseous nodules in tracheobronchial lymph nodes. Multifocal nodules on all 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 (large multinucleated cells with horseshoe-shaped nuclei). Fibrous connective tissue
• Diagnostic tests: Tuberculin test (antemortem), PCR, Special stains: Acid-fast (Ziehl-Nielson), Culture

Ovine Adenovirus

• Viral disease in Sheep and Goats
• Causes respiratory disease

Respiratory Syncytial Virus (RSV)

• Viral disease in Sheep and Goats
• Causes respiratory disease

Lymphoid Interstitial Pneumonia (Maedi)

• Viral disease in Sheep and Goats
• Slow-growing, progressive disease affecting the lungs
• Caused by a lentivirus

Caprine Arthritis Encephalitis (CAE)

• Persistent viral disease in goats
• Caused by a lentivirus
• Can cause arthritis, encephalitis, and mastitis

Peste Des Petits Ruminants (PPR)

• Highly contagious viral disease of sheep and goats
• Caused by a morbillivirus

Sheep Pox

• Viral disease in Sheep and Goats
• Causes skin lesions and can affect the respiratory system

Caseous Lymphadenitis (CLA)

• Bacterial disease in Sheep and Goats
• Caused by Corynebacterium pseudotuberculosis
• Characterized by abscesses in lymph nodes

Muellerius capillaris

• Parasitic disease in Sheep and Goats
• Lungworm that causes subpleural nodules in the dorsal region of the caudal lung lobes

Hydatid Cyst

• Intermediate stage of Echinococcus granulosus (tapeworm)
• Can be found in the lungs of sheep and goats

Canine Influenza (CIV)

• Viral disease in Dogs
• Often a mild disease but can cause severe pneumonia in young dogs
• Caused by influenzas A and B

Canine Adenovirus

• Viral disease in Dogs
• Causes respiratory disease and hepatitis

Canine Distemper

• Highly contagious disease of young dogs
• Morbillivirus (paramyxoviridae)
• Multisystemic disease: Conjunctivitis, Rhinitis, Bronchointerstitial Pneumonia, Enteritis, Skin: Parakeratosis (Paws), Encephalitis

Canine Herpesvirus

• Viral disease in Dogs
• Causes respiratory disease and abortion

Feline Calicivirus 

• Viral disease in Cats
• Causes respiratory disease

Feline Rhinotracheitis

• Viral disease in Cats
• Causes upper respiratory tract infections

Feline Infectious Peritonitis (FIP)

• Viral disease in Cats
• Caused by feline coronavirus
• Can cause a fatal, multisystemic disease

Pleuritis (Pleurecy)

• Inflammation of the pleura
• Can be caused by a variety of factors (infections, trauma, tumors)
• Abnormal contents in the pleura: Pneumothorax (accumulation of gas), Hemothorax (hemorrhage), Chylothorax (accumulation of chylous fluid), Hydrothorax (accumulation of clear fluid), Pyothorax (accumulation of pus)

Lung and Pleural Tumors

• Relatively rare in animals compared to humans
• More common in dogs and cats
• Metastatic sarcoma is a concern
• Types: Epithelial (adenoma or carcinoma)

Test your knowledge on equine respiratory diseases including Equine Viral Rhinopneumonitis, Equine Influenza, and Rhodococcal Pneumonia. This quiz covers causes, symptoms, and complications associated with these conditions affecting horses. Perfect for veterinary students or horse enthusiasts looking to expand their understanding.