Lower resp. diseases of ruminants and equine Flashcards
Lower respiratory distribution
Cranial ventral fibrin, suppurative: bacteria
In lung parenchyma: viral
Multifocal and nodular: neoplasia
Bovine enzootic pneumonia (calf pneumonia)
Begins with an acute resp. viral infection or Mycoplasma sp.
What causes bovine enzootic pneumonia
From environment (poor ventilation, humidity, crowing) or genetic predispositions (BLAD)
Bovine respiratory syncytial virus
Pneumovirus, resp. disease in cattle
Interstitial pneumonia with necrosis of bronchioles, bronchi and alveolar epithelium
Multi-nucleated cells with intracytoplasmic IBS
Shipping fever
Acute resp. disease in cattle
M. haemolytica and P.multocida
Poor nutrition, fatigue, extreme conditions, shipping and viral infection
M. haemolytica
Biotype A causes severe lesions
Alone incapable of causing disease due to rapid clearance
Gross appearance of an animal with shipping fever
Fibrinous bronchopneumonia, fibrous pleuritis, pleural effusion, distension of interlobular septae by fibrin and edema, fibrous adhesions (chornic)
Histopathic lesions of shipping fever
Areas of necrosis rimmed by degenerate neutrophils (oat cells), macros, edema and fibrin
Histophilus Somni
Colonizes nasal cavity of normal cattle
Stress predisoposes to infection
Small, G- coccobacillus
H. Somni can survive in ____________
Bovine monocytes
Respiratory histophilosis
Produces suppurative and fibrinous bronchopneumonia
Predisposing conditions are stress or viral infection
Mycobacterium
G+ rod, acid fast stain
Prevents lysosomal activity → survives in macros
What do mycobacterium produce
Tubercle with aggregates of macros, lymphos, and multinucleated giant cells in LNs and @ primary site
Tuberculosis
Cattle with M. bovis
Humans infected by drinking unpasteurized milk
Inhalation of organism and spread through lymphatics
Gross lesions of tuberculosis
Nodules on lungs and pleura → emaciation
Central necrosis and suppuration