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
Histopath lesions of tuberculosis
Granulomatous response
Macros and giant cells surrounding a center of necrosis
Mineralization
Acute bovine pulmonary edema and emphysema
Atypical interstitial pneumonia
Caused by pneumotoxins and hypersensitivity rx (environment and reinfected with D. viviparous)
Pneumotoxins causing edema and emphysema
Lush green pasutre
Moldy sweet potato
Perilla mint
Ovine Pneumonic manheimiosis
Similar to shipping fever
Most common and significant resp. disease of sheep
M. haemolytica present with Biberstenia trehalosi → septicemic pasteurellosis
What causes septicemic pasteurellosis
B. trehalosi in sheep >5 months
M. haemolytica in sheep <2 months
Effects of septicemic pasteurellosis
Necrotizing pharyngitis and tonsillitis
Pulmonary congestion and edema with petecchiation
Hepatic necrosis
Ovine progressive pneumonia (visna/ maedi virus)
Small ruminant lentivirus
Transmitted via ingestion of colostrum and inhalation of resp. secretion
Persistent life-long infection of sheep
Cs of ovine progressive pneumonia
Dyspnea and progressive emaciation with good appetite
Death inevitable once signs develop
Maedi (shortness of breath)
Lesions of OPP
Gross: severe interstitial pneumonia, lungs fail to collapse , rib imprints in lung tissue
Histo: infiltration of lymphos
Caprine arthritis- encephalitis (CAE)
Small ruminant lentivirus- retroviral disease of goats
Can cause lymphocytic interstitial pneumonia
Forms of CAE
CNS of kids: nonsuppurative leukoencephalomyelitis
Joints of adults: nonsuppurative arthritis and synovitis
Which bacteria causes Tuberculosis in small ruminants
M. bovis or M. avium
Equine influenza
Orthomyxovirus Type A influenza virus
Reportable
Mild self-limiting interstitial to bronchointerstitial pneumonia
Equine viral rhinopneumonitis
Weanlings between 4-8months
Equine herpesvirus 1 and 4
Bronchointerstitial pneumonia associated with secondary bacteria infections
Equine viral arteritis (EVA)
Arterivirus
Transmitted by vectors (mosquitos), resp. route and venearal
Lesions of EVA
Serous or mucopurulent rhinitis, conjunctivitis, palpebral edema, hemorrhage
Vasculitis, interstitial pneumonia with hyperplasia of type 2 pneumocytes
Rhodococcosis
Cause of morbidity and mortality in foals
Associated with immunosuppression
Causes fatal bronchopneumonia and ulcerative enterocolitis
Pathogenesis of Rhodococcosis
Enter lung → destruction of macros → release of bacterial cytotoxins → extensive necrosis
Pyogranulomatous pneumonia and lymphadentitis with abscesses
Chlamydophila psittaci
Lime green diarrhea, keratoconjunctivitis, etc.
Pneumocystis carinii and adenovirus
Combined immunodeficiency (CID) foals
Large basophilic intranuclear inclusions (adeno)
Eosinophilic granular exudate in alveolar spaces (pneumocystis)