Causative Agents-Respi-Patho2

Porcine Cytomegalovirus (Herpesvirus)

Mild rhinitis, sneezing, nasal discharge, and inclusion bodies in nasal epithelium in pigs.

Streptococcus equi (Strangles)

Fever, mucopurulent nasal discharge, and swollen mandibular lymph nodes in horses.

Mannheimia haemolytica or Pasteurella multocida (Lobar Pneumonia)

Cranioventral lung consolidation, hepatization, fibrinous exudate, and necrosis in cows.

Tracheal Collapse (weakness in tracheal cartilage)

Chronic honking cough, dorsoventral tracheal flattening, and widened dorsal tracheal membrane in dogs.

Equine Laryngeal Hemiplegia (left recurrent laryngeal nerve damage)

Difficulty breathing, roaring sound, and atrophy of the left cricoarytenoids dorsalis muscle in horses.

Congestive Heart Failure (left-sided heart failure)

Pulmonary congestion, dark red lungs, and "heart failure cells" in cows.

Cryptococcus neoformans

Chronic sneezing, nasal discharge, conjunctivitis, and yeast cells with thick capsules in cats.

Equine Herpesvirus-4 (EHV-4)

Nasal discharge, mild fever, cough, and Equine Herpesvirus (EHV-4) infection in foals.

Metastrongylus spp. (lungworm)

Small gray nodules in caudal lung lobes and peribronchial lymphoid hyperplasia in cows.

Guttural Pouch Mycosis (fungal infection)

Dysphagia, epistaxis, and fungal plaques in the guttural pouch in horses.

Toxigenic Pasteurella multocida and Bordetella bronchiseptica \

Causes Atrophic Rhinitis, Nasal deformity, mucopurulent nasal discharge, and severe atrophy of nasal conchae in pigs

Interstitial Pneumonia (alveolar wall injury)

Alveolar septal damage, hyaline membrane formation, and type II pneumocyte hyperplasia in dogs.

Honker Syndrome (tracheal edema syndrome)

Dyspnea, "honking" cough, tracheal edema, and hemorrhage in cows.

Mannheimia haemolytica (fibrinous pleuropneumonia)

Severe fibrinous pleuropneumonia, distended interlobular septa, and fibrin deposition in cows.

Ethmoid Hematoma (vascular expansion and hemorrhage)

Swollen nasal passage, epistaxis, and mass in the ethmoid region in horses.

Feline Infectious Peritonitis (FIP)

Dyspnea, pleural effusion, and thick yellow fluid with high protein content in cats.

Histoplasma capsulatum (fungal infection)

Granulomatous nodules with necrotic centers, giant cells, and macrophages in dog lungs.

Equine Laryngeal Hemiplegia (left recurrent laryngeal nerve damage)

Exercise intolerance, inspiratory noise, and incomplete arytenoid cartilage abduction in horses.

Chronic Obstructive Pulmonary Disease (COPD)

Progressive dyspnea, expiratory wheezing, bronchiolar hyperplasia, and mucus accumulation in cows.

Pulmonary Adenocarcinoma (malignant epithelial tumor)

Coughing, difficulty breathing, and nodular masses with pleomorphic epithelial cells in dog lungs.

Mycobacterium bovis or Mycobacterium tuberculosis (Tuberculosis)

Multiple small lung nodules with caseous necrosis, macrophages, and giant cells in dogs.

Nocardiosis

Is a chronic suppurative granulomatous process caused by Nocardia asteroides, often affecting the pleural cavity in dogs and cats.

Is a rare neoplasm of the pleura, often associated with prolonged exposure to asbestos.

Mesothelioma

Pleuritis

or inflammation of the pleura, is often secondary to pneumonia and can be caused by Haemophilus parasuis infection in pigs.

Primary Lung Tumor

Is a common primary lung tumor in dogs, characterized by malignant transformation of alveolar epithelial cells

Embolic Pneumonia

Caused by the entrapment of septic emboli in the pulmonary vasculature, leading to multifocal lesions in the lungs.

Uremic Pneumopathy

Characterized by degeneration and calcification of smooth muscle in the respiratory bronchioles, often seen in animals with terminal kidney disease.

Focal Abscessation

Is often caused by Corynebacterium pseudotuberculosis, leading to abscess formation in the lung parenchyma and pleural adhesions.

Parasitic pneumonia

Caused by Dictyocaulus filaria results in obstruction of small bronchi by adult worms and exudates, commonly seen in lambs and kids.

Aspiration Pneumonia

Results from the inhalation of foreign material, such as medication, leading to severe necrotizing and suppurative reactions.

Lipid Pneumonia

Occurs due to the aspiration of oil droplets, often seen in cats after forceful administration of mineral oil.

Hypersensitivity-Induced Interstitial Pneumonia

Characterized by lymphocytic infiltration and fibrosis of alveolar walls, often leading to a "meaty" appearance of the lungs

Bacterial Granulomatous Pneumonia

Caused by Mycobacterium bovis, is characterized by caseous granulomas with epithelioid cells and giant cells

Fungal Granulomatous Pneumonia

Caused by Cryptococcus neoformans, is characterized by non-caseous granulomas with epithelioid cells and giant cells.

Proliferative Phase of Interstitial Pneumonia

Characterized by hyperplasia of type II pneumocytes and fibrosis, leading to a rubbery consistency of the lungs.

Exudative Phase of Interstitial Pneumonia

pneumonia is characterized by hyaline membrane formation, sloughing of type I pneumocytes, and alveolar damage.

Contagious Bovine Pleuropneumonia

Is characterized by fibrinous pleuropneumonia and distention of interlobular septae, caused by Mycoplasma mycoides subsp. mycoides.

Granulomatous Pneumonia

characterized by caseous granulomas with epithelioid cells and giant cells, often caused by fungal agents like Blastomyces dermatitidis.

Interstitial Pneumonia

Characterized by alveolar wall thickening, hyperplasia of type II pneumocytes, and fibrosis, giving the lungs a "meaty" appearance

Suppurative Bronchopneumonia

Characterized by cranioventral consolidation, mucopurulent exudates, and neutrophilic infiltration, often caused by Pasteurella multocida.

Lobar or Fibrinous Bronchopneumonia

Characterized by consolidation of an entire lobe, fibrinous exudates, and is commonly caused by Pasteurella hemolytica in cattle.

Mycoplasma Pneumonia

Is characterized by chronic lymphocytic infiltration in the bronchioles and alveoli, commonly seen in pigs.

Viral Pneumonia

Characterized by lymphocytic infiltration in the alveoli and interstitium, often causing interstitial pneumonia.

Gray Hepatization Stage of Pneumonia

Characterized by macrophage infiltration and absence of hyperemia, indicating a chronic process.

Red Hepatization Stage of Pneumonia

Characterized by hyperemia, fibrin exudation, and a liver-like consistency of the lungs.

Bronchopneumonia

Characterized by cranioventral consolidation of the lungs due to suppurative exudates in the alveoli and bronchioles.

Pulmonary Embolism

In heartworm disease is caused by Dirofilaria immitis, leading to pulmonary hypertension and right ventricular hypertrophy.

Pulmonary hemorrhage

Result from trauma, leading to rupture of blood vessels and severe epistaxis

Permeability Pulmonary Edema

Caused by endothelial damage, leading to high-protein fluid leakage into the alveoli, which appears deeply eosinophilic on histopathology.

Hemodynamic Pulmonary Edema

Due to decreased osmotic pressure (e.g., hypoalbuminemia) or increased hydrostatic pressure, leading to fluid accumulation in perivascular spaces and alveoli.

Pulmonary congestion, due to congestive heart failure

Leads to accumulation of blood in pulmonary vessels, hemosiderin-laden macrophages (heart failure cells), and brownish discoloration of the lungs.

Interstitial emphysema

When air accumulates in the interlobular septa, often forming large air pockets (bullae), commonly seen in cattle.

Alveolar Emphysema

Characterized by distention and rupture of alveolar walls, leading to air bubbles in the pulmonary parenchyma.

Obstructive Atelectasis

Airway obstruction leads to lung collapse, often accompanied by emphysema in surrounding lung tissue.

Compression Atelectasis

When space-occupying lesions, such as tumors or fluid, compress the lung tissue, leading to collapse.

Hypostatic Atelectasis

Occurs when postural forces prevent adequate ventilation, leading to lung collapse, often seen in large animals kept in abnormal postures.

Neonatal Atelectasis

Is a hyaline membrane disease caused by a lack of surfactant, leading to alveolar collapse and hyaline membrane formation

Pulmonary Calcification

Occur as a sequela to uremia in dogs, leading to non-collapsing lungs and a gritty texture due to calcification.

Congenital Melanosis

Characterized by dark spots in the lungs, meninges, and other organs, commonly seen in pigs and ruminants.

Ciliary Dyskinesia

Is characterized by defective ciliary movement due to microtubule abnormalities, leading to chronic respiratory infections and infertility.

Accessory Lungs

Are congenital anomalies consisting of lobulated masses of partially differentiated pulmonary tissue that can cause dystocia if large.

Equine adenovirus infection

Infection in Arab foals with combined immunodeficiency (CID) can lead to severe pneumonia and fatal outcomes

Parasitic Rhinitis

Caused by Oestrus ovis larvae, is characterized by nasal irritation, obstruction, and mucopurulent discharge.

Mycotic Rhinitis

Caused by fungi like Cryptococcus neoformans, is characterized by granulomatous nodules in the nasal mucosa.

Feline Calicivirus Disease (FCV)

Characterized by ulcerative stomatitis, oculonasal discharge, and, in severe cases, multifocal interstitial pneumonia.

Feline Viral Rhinotracheitis (FVR)

Characterized by serous rhinitis that progresses to mucopurulent discharge, often complicated by secondary bacterial infections, caused by feline herpesvirus-1.

Infectious Bovine Rhinotracheitis (IBR)

Is characterized by serous nasal discharge, hyperemia, and ulceration of the nasal mucosa, often complicated by necrotizing bronchitis, caused by bovine herpesvirus-1.

Equine Viral Rhinopneumonitis

Can cause mild respiratory disease in young horses and abortion in mares, often due to equine herpesvirus (EHV-4).

Glanders

Caused by Burkholderia mallei characterized by nodular, suppurative lesions in the respiratory tract and skin, with granulomatous nodules containing necrotic centers.

Strangles

Characterized by suppurative rhinitis and (swollen mandibular lymph nodes) lymphadenitis, with potential dissemination leading to abscesses in organs like the lungs and liver. Causative agent Streptococcus equi subspecies equi

Atrophic rhinitis

Is characterized by mucopurulent nasal discharge, erosion of mucous membranes, and atrophy of nasal conchae, often caused by Bordetella bronchiseptica and toxigenic strains of Pasteurella multocida.

Exercise-induced pulmonary hemorrhage (EIPH)

A common cause of epistaxis in racehorses, resulting from bronchiolar damage and bleeding from the lungs during strenuous exercise.

Choanal atresia

is a congenital condition characterized by a membranous or bony obstruction of the nasal passage, leading to respiratory distress.