Respiratory 2 Flashcards
What commensals are often isolated in cases of shipping feverr?
Mannheimia haemolytica Pasturella multocida Histophilus somni Mycoplasma bovis Trueperella pyogenes
What is another name for shipping fever?
Bovine pneumonic pasturellosis.
Clinical signs of shipping fever?
Depression, anorexia
Fever
Nasal discharge
Soft, moist cough
Following stressful episode
Why is there a high mortality assoicated with shipping fever?
Bronchial obstruction with fibrinous exudates
Survivors will have irreversible lung damage —> chronic poor doers
Main lesions caused by mannheimia haemolytica ?
Dark reddish-black to grayish brown cranioventral lung lobes with marked distention fo interlobular septae by gelatinous yellow fluid
“Hepatization” — appears like liver
What is the second most common pathogen assoicated iwth shipping fever?
Pasturella multocida
T/F: pasturella is zoonotic
True
What type of bronchopneumonia does pasteurella multocida cause?
Fibrinopurulent
More chronic than M. Haemolytica
More of a pus former
Common presentation of a PM exam of a cow with pasturella multocidia infection?
Multiple coalescing abscesses
Fibrinopurulent
What can you use to treat pasturella multocidia?
Any antibiotic that has gram neg spectrum and is labelled for used in the species and production class
Adjunct—NSAIDS, corticosteroids, and vit C
Histophilus somi causes mutlisystemic diseases, what are conditions associated with this bacteria?
Bronchopneumonia Thromboembolic menigioencephalitis (TEME) Necrotic laryngitis Myocarditis Arthritis Otitis and conjunctivitis Myelitis Mastitis Myositis Abortion and other repro disorders
What is the most common manifestation of histophilus somi in lightweight calves?
Bronchopneumonia
Known to produce excess fibrin on pleural surface
What is the most important virulence factor for histophilus somni?
Intracellular survival and replication
T/F: there is no vaccine for histophilus somni
False
They are available in combination with other BRD antigens
What two species of mycoplasma have been reported as significant agents in bovine respiratory disease?
Mycoplasma dispar — pneumonia is often seen shortly after grouping dairy calves that have been raised individually
Mycoplasma bovis —more severe presentations
What type of pneumonia does mycoplasma cause?
Lobar bronchopneumonia
With severe peribronchial cuffing, primarily in highly stressed young calves
What is a characteristic presentation with M bovis ?
Pneumonia - arthritis syndrome
Calves present with upper resp signs at 2-4 weeks and some with polyarthritis and tenosynoviitis
Can have otitis media
Lesions on necropsy of a cow..
Suppurative bronchopneumonia
Edematous septa and pleuritis
Coagulative necrosis present as a purulent center arising from an affected bronchiole, surrounded by histiocytic and mononuclear infiltrate with minimal encapsulation
Top DDX?
Mycoplasma bovis
How can you confirm diagnosis of mycoplasma bovis?
Immunohistochemistry gold standard
PCR — use with caution because a low level of M bovis can be insignificant
Treatment of mycoplasma bovis?
Resflor
Nuflor
Draxxin
Baytril
What is the pathophysiology of acute bovine pulmonary emphysema (ABPE)
Some inciting cause leads to local generation of free radicals in the lung —> injury and necrosis of type I pneumocytes —> acute exudative phase (edema and hyaline membrane) —> acute proliferation phase (hyperplasia of type II pneumocytes) —> chronic interstitial pneumonia (interstitial cell infiltrates, fibrosis, emphysema)
Acute bovine pulmonary emphysema is AKA __________________?
Atypical interstitial pneumonia
Fog fever
What is the EDx of fog fever?
I-tryptophan present in pasture —> metabolized in the rumen to 3-methylindole —> absorbed in bloodstream and carried to lungs
Causes extensive and selective necrosis of bronchiole cells
—> increase alveolar permeability, leading to edema, thickening of the alveolar interstitium, and alveolar interstitial emphysema
Purple mint, moldy sweet potatoes, stinkwood, rapeseed, and kale
Clinical signs of fog fever?
Severe respiratory distress develops within 10days of the abrupt pasture change, and cattle develop expiratory dyspnea, oral breathing, and evidence of emphysema within the lungs and even SQ along the back.
How can you help manage fog fever?
Allow younger animals to graze the pastures first
Feeding ionophores changes volatile fatty acid production —> reduce 3 methylindole production
What lungworm is found in cattle?
Dictylocaulus viviparous
What lesions does dictylocaulus viviparous cause?
Usually in the caudal lobes causing severe bronchial irritation, bronchitis, and pulmonary edema
Which is turn is responsible for lobular atelectasis and interstitial emphysema
