Bovine Respiratory Disease-Dr. French Flashcards
Where is most respiratory pathology going to be auscultated?
On the right side due to increased lung lobes
Major branching of bronchi occurs to middle/accessory lung lobe on R side
What is the first lung lobe to be affected?
The R accessory lung lobe
When are we most concerned about respiratory pathology?
When there is an absence of air flow
If we suspect a bacterial infection, where will majority of the problem lie in the lungs?
Ventral due to the high cell count (heavy)
What is the characteristic stance of respiratory disease?
Stand motionless, elbows abducted, head lowered w/ neck extended, open mouth breathing
Where would you auscultate respiratory pathology if the cause was interstitial infection?
All over the lung fields
What is the most important thing to listen for when determining if there is respiratory pathology?
Air flow- when there is absence we should be concerned
What would we suspect if a patient presents with a non-productive cough?
Tracheal irritation
What would we suspect if a patient presents with a productive cough?
Removal of excess mucous, inflammatory products or foreign material
What would we suspect if a patient presents with sneezing?
Allergic rhinitis
What would we suspect if a patient presents with expiratory grunting?
Thoracic pain (pleuritic and severe pneumonia)
What would we suspect if a patient presents with inspiratory and expiratory grunting?
Cranial abdominal pain
What are some differentials if stridor is heard on inspiration?
Decrease in cross-sectional area of larynx
Laryngeal calf diphtheria
What are some differentials if snoring is heard on PE?
Retropharyngeal abscess
External pressure on larynx or upper airway
Balling gun induced in older animals
What clinical presentation will be observed in a cow with sinusitis?
Obvious discharges from head, squinting eyes, head pressing, reluctant for a head exam
What might you notice when doing a sinus percussion on a patient with sinusitis?
Dull resonance (normal will sound hollow)
How do nasal obstructions present?
Unilateral airflow deficit and respiratory stridor
OR
Severe dyspnea w/ open mouth breathing from bilateral obstruction
If both nostrils have reduced airflow, where is the mass located?
Caudal to nasal septum
What can a patient be put on if the nasal obstruction is caused by a fungal mass from Actinobacillosis or Nocardiosis?
Na Iodide IV solution
What are some common causes of pharyngeal/retropharyngeal abscesses?
Inappropriate use of oral dosing equipment
Stomach tubes
Coarse feedstuffs
What are some CS of a patient with a pharyngeal/retropharyngeal abscess?
Head/neck extension, pharyngeal swelling, increased water/decreased feed, malodorous breath, severe pain on palpation
What occurs secondary to condritis of laryngeal cartilages?
Laryngeal/Pharyngeal dysfunction
What is a common name for Bovine Herpes Virus 1?
Red nose
What are the differences in the three subtypes of Bovine Herpes Virus 1?
- 1: respiratory disease and abortion
- 2a: genital tract infections
- 2b: respiratory disease, no abortions
T/F: all three subtypes of BHV1 share Ag properties so the vaccination offers cross protection?
TRUE
What age is BHV1 most commonly seen?
In calves >6 months of age
What is a common way to dx BHV1?
Nasal swabs for viral isolation
What two respiratory diseases lead to mucosal sloughing?
BHV1 and Bovine Viral Diarrhea Virus
What are some CS of BHV1?
Fever, rhinitis, conjunctivitis, labored breathing, hyperemia of muzzle, pustules and diphtheretic plaques
Primary lung lesions NOT seen
Parainfluenza-3 most commonly affects what type of cells and in what location?
Epithelial cells of upper respiratory tract
Damage to mucociliary transport leading to mild bronchitis
What is a characteristic sound produced in PI-3?
Tracheal rales
What will be found on PM exam from a calf with PI-3?
Mild interstitial pneumonia
Intracytoplasmic inclusion in mucosa
When is bovine coronavirus most commonly seen?
Post stressful event
Can commonly contribute to development of calf scours
In patients with bovine respiratory syncytial virus, the lungs cannot fully expand with air, what is a result of this?
Pulmonary emphysema and SQ emphysema
What group of cattle does BRSV most commonly occur in?
YOUNG CATTLE- 3-12 months old (unvaccinated)
What is a potential reproductive effect associated with BRSV and what causes it?
Abortions caused by pyrexia
What is a common diagnostic test done for BRSV?
IHC of lung tissue
What is the most common subtype of BVD seen in the US?
1b
Who is the most important reservoir for BVD?
PI calves
These calves are infected in-utero, born infected, and immunotolerant to BVD that causes infection in other calves/cows
What is the gold standard dx test for BVD and what is our source of collection?
Virus isolation through nasal swabs
What is the most common pathogen associated with shipping fever?
mannheimia haemolytica
When is a soft cough seen with mannheimia haemolytica infection?
6-10 days post stressful event
Why is there high mortality seen w/ mannheimia haemolytica?
Bronchial obstruction w/ fibrinous exudates
What does mannheimia haemolytica cause?
Severe fibrinous pleuropneumonia
What pathology is seen with the lung lobes on necropsy of a patient with mannheimia haemolytica?
Cranioventral lung lobe pathology
Dark reddish-black to grayish-brown and firm with marked distention of interlobular septae by gelatinous yellow fluid
What is the second most common pathogen associated with shipping fever?
Pasteurella mulocida
What does pasteurella multocida cause?
Fibrinopurulent bronchopneumonia
“Pus former”-multiple coalescing abscesses are common
This bacteria causes excess fibrin on pleural surface of lungs within 2 weeks of arrival in feedlot leading to bronchopneumonia
Histophilus somni
What are the two species of mycoplasma that are common?
Mycoplasma dispar- seen shortly after grouping dairy calves that have been raised individually in hutches
Mycoplasma bovis- more severe presentations
What does Mycoplasma cause?
Lobar bronchopneumonia w/ severe peribronchial cuffing
What is a characteristic presentation of mycoplasma?
Pneumonia-arthritis syndrome
Can have otitis media
What lesions are seen with mycoplasma?
Coagulative necrosis lesions present as a purulent center
What type of immune response is stimulated by Mycoplasma?
TH2 immune response
What is the dx method of choice for mycoplasma?
Immunohistochemistry of lung sections
Also known as “Fog Fever”
Acute bovine pulmonary emphysema
What is the pathophysiology of Fog Fever?
3-methylindole causes extensive and selective necrosis of bronchiolar cells and type I pneumocytes and increases alveolar permeability leading to edema, thickening of alveolar interstitium and interstitial emphysema
When is Fog Fever commonly seen?
Cattle that abruptly start grazing lush pastures after being on poor quality pasture or drylot
Where is fog fever most noticable in the lungs?
Caudal lung lobes
What are some CS of Fog Fever?
Severe respiratory distress 10 days post pasture change
expiratory dypnea
Oral breathing
Evidence of emphysema in lungs (+/- SQ emphysema)
What is a tx option for fog fever?
Feeding ionophores- will alter rumen metabolic profile reducing 3-methylindole
What causes “eosinophilic syndrome”?
Verminous pneumonia
Where do adult parasites live in the lungs?
Caudal lobes leading to severe bronchial irritation, bronchitis and pulmonary edema
Responsible for lobular atelectasis and interstitial emphysema
When is verminous pneumonia most commonly seen?
In calves during their first summer grazing
