Respiratory disease Flashcards
What is a normal RR in a ruminant?
12-24bpm
What are wheezes associated with? What are crackles associated with?
Wheezes- airway narrowing, often at the end of expiration
Crackles- airway collapse or small airway disease, often at the end of inspiration
What causes pleural friction rubs?
Underlying pleuritis
What is decreased bronchovesicular sounds associated with?
Consolidating pulmonary parenchyma, mass, or pleural effusion
What are hyper-resonant lung sounds associated with?
Pneumothorax
Describe stridor
Type of wheeze focused over extrathoracic airways, primarily heard during inspiration, often associated with laryngeal or tracheal disease
Describe what causes an alveolar pattern
Air in alveoli has been replaced with higher density material (exudate, hemorrhage, edema); seen with cranioventral pneumonia
Describe what causes a bronchial pattern
Bronchial wall is infiltrated by cells or fluid or peribronchial space is replaced by cells or fluid, causes enhanced radiographic visualization of the bronchial tree, typically seen with chronic inflammation and allergies
What causes a structural and non-structural interstitial pattern?
Structural- aggregation of cells that displace normal lung tissue (tumor, abscess, granuloma)
Non-structural- diffuse, fluid, cells, or fibrin coalescing together (cancer or edema)
What disease is usually seen cranioventral on radiographs? Caudo-dorsal?
Cranioventral- bronchopneumonia, some infectious pneumonias
Caudo-dorsal- allergies, environmental irritation, parasitic and viral diseases
What is the indication for nasopharyngeal swabs?
Detection of viral and bacterial diseases in the upper respiratory tract
What tests are used in conjunction with a nasopharyngeal swab?
PCR, antigen detection ELISA, virus identification and isolation
What is the indication for a transtracheal wash?
Identifies infectious agents of the lower respiratory tract or pleura, good for bacterial culture
Which airway sampling technique should be performed first?
Transtracheal wash- need to avoid contamination
What is the indication for bronchoalveolar lavage?
To obtain samples that aren’t appropriate for bacterial culture or identification of an infectious organism, more useful for cytology
What is the normal neutrophil percentage on BAL of a calf?
5-20%
What is dominant presence of neutrophils on BAL indicate? What about eosinophils?
Neutrophils- bacterial infection
Eosinophils- parasitic infection
How much of the fluid introduced on a BAL will be retrieved?
About 1/3 of it
Should you sedate an animal for BAL? Why or why not?
No; it will suppress their cough response making performance difficult
Describe normal fluid from thoracocentesis
Odorless, pale yellow transparent, pH ~7.2, 2.5g/dL protein, 10,000cells/uL, predominately macrophages
Describe abnormal fluid from thoracocentesis
Variable color and odor, pH <7.2, protein >2.5g/dL, nucleated cells >10,000cell/uL, variable cellular composition, high lactate and low blood glucose
Where do you perform thoracocentesis on a ruminant?
6th or 7th intercostal space at the level of the costochondral junction along the cranial aspect of the rib
What symptoms are consistent with upper respiratory disease?
Nasal discharge, sneezing, coughing, foul smelling breath
What symptoms are consistent with lower respiratory disease?
Fever, cough, abnormal auscultation, anorexia, malaise
Which species get Oestrus ovis?
Sheep > goats, rarely cattle
Describe the pathogenesis of O. ovis
Larval stage travels to ethmoid turbinates and molts, travels to sinuses and molts again, returns to nasal passage and is sneezed out
What clinical signs are consistent with O. ovis infection?
Mucoid to mucopurulent nasal discharge, sneezing, nasal rubbing, inspiratory stridor
What are reasonable differential diagnoses for O. ovis infection?
Nasal foreign body, rhinitis, nasal adenocarcinoma, trauma, sinusitis
How is O. ovis infection diagnosed?
Radiography, clinical signs, endoscopy
How is O. ovis treated? What treatment is approved in the US?
Oral ivermectin, pour on eprinomectin or injectable doramectin
No treatments approved in the US, not typically seen here
What are causes of sinusitis?
Dehorning (frontal), infected tooth (maxillary), neoplasia, trauma, actinomyces, respiratory virus
What are common isolates from sinusitis infected tissue?
Trueperella, Pasteurella
What clinical signs are associated with acute sinusitis?
Weeks to months post event (ex. dehorning), unilateral, febrile, mucopurulent discharge from horn tip, anorexic, lethargic
What are clinical signs associated with chronic sinusitis?
Unilateral or bilateral nasal discharge, foul breath, blepharospasm, holding head at an odd angle, neuro signs, fever uncommon
How is sinusitis diagnosed?
History and clinical signs + percussion (dull and painful), radiographs, and sterile collection of fluid for culture
How is sinusitis treated?
Lavage, drainage with trephination, antimicrobials (procaine penicillin G, oxytetracycline), NSAIDs, good prognosis with resolution ~10-14d
What are potential sequelae of pharyngeal trauma?
Hematoma, granuloma, cellulitis, abscess
What are causes of pharyngeal trauma?
Balling gun, dose syringe, speculum, stomach tube
Which bacteria are commonly involved in pharyngeal trauma and abscess?
Trueperella pyogenes, Actinobacillus, Pasteurella, Bordetella, Fusobacterium necrophorum
What clinical signs are associated with pharyngeal trauma/abscess?
Inspiratory dyspnea, extended head and neck, ptyalism, pain on swallowing, nasal discharge, subsequent aspiration pneumonia
What are reasonable differential diagnoses for pharyngeal trauma?
Neoplasia, LSA, rabies, botulism, necrotic laryngitis, trauma, edema
How is pharyngeal trauma/abscess diagnosed?
Examination with a mouth gag and/or endoscopy, radiographs
How is pharyngeal trauma or abscess treated?
Drain abscess, antimicrobial therapy (procaine penicillin G, oxytetracycline), NSAIDs, tracheostomy if necessary, supportive care
What are the causative agents of necrotic laryngitis (AKA calf diphtheria or laryngeal necrobacillosis)
Fusobacterium necrophorum and Trueperella pyogenes
What is needed for bacterial invasion (necrotic laryngitis)?
Laryngeal contact ulcers
What are sequelae of necrotic laryngitis?
Decreased growth rate, secondary bacterial pneumonia
Which animals are predisposed to necrotic laryngitis?
Young (3-18m) calves, crowded feedlot animals, higher incidence in fall and winter
What are clinical signs of necrotic laryngitis?
Painful, moist cough, inspiratory dyspnea, open-mouth breathing, head and neck extended, increased salivation, painful swallowing, visibly swollen larynx, cough upon stimulation, fever, anorexia, hyperemic mm, bilateral nasal discharge, foul breath
Describe the progression of necrotic laryngitis
Acute onset, most calves die within 2-7 days if untreated, recovered cases may have chronic changes
What are differential diagnoses for necrotic laryngitis?
Pharyngeal trauma, viral laryngitis, Actinobacillosis, neoplasia
How is necrotic laryngitis diagnosed?
Clinical signs, endoscopic exam, CBC with acute sepsis
How is necrotic laryngitis treated?
Antimicrobial therapy (oxytet, PPG, sulfonamides, florfenicol), NSAIDs, tracheostomy, supportive care, steroids if not immunosuppressed/septic yet
What is the prognosis of necrotic laryngitis?
Fair with early detection and aggressive therapy
Describe tracheal edema syndrome
AKA tracheal stenosis or honker syndrome; cause unknown, signs include coughing, dyspnea, and stertor, extensive edema and hemorrhage of teh dorsal wall fo the trachea
What are differentials for acute dyspnea?
Pharyngeal trauma, necrotic laryngitis, IBR, laryngeal abscess
Which animals are predisposed to acute dyspnea?
Heavy feedlot cattle, in the summer
Which animals are predisposed to chronic cough?
Smaller frame cows
What are differentials for chronic cough?
Necrotic laryngitis, pneumonia
How is chronic cough treated?
Steroids, antibiotics (especially if you can’t differentiate from pneumonia)
Do animals with bronchopneumonia appear sick? Do animals with interstitial pneumonia appear sick?
Bronchopneumonia- yes, depressed, febrile, signs of sepsis
Interstitial pneumonia- no, usually not systemically sick
What is the final outcome of bovine respiratory disease complex?
Bronchopneumonia
What are causative agents of bronchopneumonia?
Many viruses and bacteria
BRV, BHV/IBR, BRSV, BVDV, PIV-3, etc.