Canine Upper Respiratory Disease: Differential Diagnosis and Management

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-11

Key Takeaways

• Distinguishing upper respiratory disease requires precise anatomic localization (nasal, pharyngeal, laryngeal, tracheal) and consideration of signalment; young dogs are prone to infectious or congenital causes, while older dogs may present with neoplasia or dental disease.
• Nasal discharge lateralization is critical: unilateral suggests foreign body, neoplasia, or dental disease, whereas bilateral points towards viral, bacterial, or fungal etiologies.
• Computed tomography (CT) is the preferred imaging modality for nasal and sinus assessment due to its superior bony and soft tissue detail, surpassing the low sensitivity of skull radiographs for detecting masses and foreign bodies.
• PCR panels for infectious agents offer high specificity but variable sensitivity; a negative result does not definitively exclude infection, and interpretation must be integrated with clinical signs, cytology, and response to therapy.
• Biopsy and histopathology remain the diagnostic standard for definitive diagnosis of neoplasia, as CT findings alone are rarely conclusive, and targeted sampling is crucial due to potential necrosis within lesions.
• Urgent stabilization is paramount for patients exhibiting signs of upper airway obstruction such as stertor at rest, inspiratory effort with abdominal component, or cyanosis, necessitating oxygen support and potentially sedation or intubation.

Upper respiratory disease in dogs encompasses disorders of the nasal passages, pharynx, larynx, trachea, and associated sinuses. This article provides a diagnostic framework for the practicing veterinarian, distinguishing infectious, inflammatory, structural, and neoplastic causes. It addresses the clinical reasoning pathway from signalment and history through physical examination, imaging, and targeted laboratory testing, with emphasis on conditions that mimic one another and on management strategies tailored to specific diagnoses. Lower respiratory conditions, including bronchial and parenchymal disease, are excluded from this discussion.

The reader is assumed to be a qualified veterinary clinician comfortable with advanced diagnostic techniques and therapeutic decision-making. The article answers the practical question of how to approach a dog presenting with nasal discharge, sneezing, stertor, coughing, or inspiratory dyspnea when the anatomic origin is clearly above the thoracic inlet. Where the evidence base is limited or contested, this is stated explicitly, and the reader is directed to consult current formulary and label references before prescribing.

At a Glance

Anatomic and Physiologic Basis of Upper Respiratory Signs

The upper respiratory tract in dogs serves warming, humidification, filtration, and olfaction. The nasal cavity is divided by the septum and contains complex turbinate structures lined by respiratory epithelium with abundant goblet cells and seromucous glands. The nasolacrimal duct drains into the ventral meatus, which explains epiphora in some nasal diseases. The pharynx is a shared conduit for air and ingesta, and its muscular coordination is essential for normal swallowing and breathing. The larynx guards the lower airway during deglutition and modulates airflow during exercise and phonation.

Brachycephalic breeds present a particular challenge because their conformational anatomy alters normal airflow dynamics. Stenotic nares, elongated soft palate, and hypoplastic trachea create turbulent flow and increased negative pressure during inspiration, which can exacerbate or mimic primary upper respiratory disease. The clinician must distinguish conformational obstruction from acquired pathology in these patients, and both may coexist.

Mucociliary clearance is the primary defense mechanism of the nasal and tracheal epithelium. Ciliated cells propel a mucus layer toward the pharynx, where it is swallowed. Conditions that impair ciliary function, such as chronic infection or primary ciliary dyskinesia, result in mucus accumulation and secondary bacterial colonization. The nasal cavity also harbors a commensal microbial population that can complicate interpretation of culture results, particularly when samples are obtained from the nasal vestibule instead of deep within the cavity.

Infectious Causes and Diagnostic Reasoning

Viral pathogens are the most common infectious causes of acute upper respiratory disease in dogs. Canine distemper virus, canine adenovirus type 2, canine parainfluenza virus, and canine respiratory coronavirus all target respiratory epithelium and produce similar early clinical signs. Bordetella bronchiseptica and Mycoplasma species frequently act as secondary invaders following viral damage. The clinical overlap among these agents is substantial, and empirical treatment is often initiated before a specific etiologic diagnosis is pursued.

The diagnostic value of PCR panels depends on sampling technique and timing. Deep nasal or oropharyngeal swabs collected during the acute phase yield the highest sensitivity, but a negative result does not exclude infection. As noted in the feline literature on calicivirus, a related RNA virus with high genetic variability, negative PCR results can occur in infected animals and healthy carriers can test positive, a principle that applies equally to canine respiratory pathogens. Serology is rarely useful in the acute setting because it reflects prior exposure instead of active infection.

Bacterial culture from nasal swabs is frequently misleading because the nasal cavity is not sterile. Quantitative culture from protected brush samples or tissue biopsy provides more meaningful results. Streptococcus equi subspecies zooepidemicus has emerged as a significant canine respiratory pathogen, particularly in crowded environments. In a study of cats seized from large-scale hoarding investigations, this organizm was identified in 55% of cats with upper respiratory signs, demonstrating its importance in high-density housing. Similar principles apply to canine shelters and boarding facilities, where multiple pathogens circulate simultaneously and coinfection is common.

Fungal rhinitis, most commonly caused by Aspergillus fumigatus, typically presents as a chronic, progressive disease in middle-aged, immunocompetent dogs. The classic findings of depigmentation of the nasal planum, pain on nasal percussion, and destructive turbinate changes on imaging help distinguish fungal disease from neoplasia, though both can produce similar clinical signs. Serology for Aspergillus antibodies has moderate sensitivity, and definitive diagnosis requires visualization of fungal plaques on rhinoscopy or positive culture from tissue biopsy.

Noninfectious Differential Diagnoses

Foreign bodies are a common cause of acute, unilateral nasal discharge and sneezing in dogs. Grass awns, seeds, and plant material are the usual offenders, and the clinical history often includes sudden onset of signs during or after outdoor activity. Radiographs rarely identify organic foreign bodies, and CT or rhinoscopy is required for diagnosis and retrieval. The discharge is typically mucopurulent and may become hemorrhagic if the foreign body has been present for days or weeks.

Dental disease, particularly oronasal fistulation from maxillary premolar or molar disease, produces unilateral nasal discharge that worsens with eating. The discharge often contains food material and has a fetid odor. Oral examination under general anesthesia with periodontal probing is essential, and skull CT with dental reconstruction can identify subtle fistulae. Extraction of the affected tooth and surgical closure of the fistula is curative.

Nasal neoplasia accounts for approximately 1% of all canine cancers and is most common in older, large-breed dogs. Adenocarcinoma, squamous cell carcinoma, and undifferentiated carcinoma are the most frequent histotypes, with chondrosarcoma and lymphoma occurring less commonly. Clinical signs progress over weeks to months and include unilateral or bilateral epistaxis, nasal discharge, facial deformity, and epiphora. CT reveals a soft tissue mass with variable turbinate destruction, but imaging findings cannot reliably distinguish neoplasia from severe fungal rhinitis. Histopathology from biopsy is required for definitive diagnosis and prognostic counseling.

Diagnostic Approach and Decision Framework

The diagnostic plan should be guided by chronicity, lateralization, and response to initial therapy. Acute signs of less than 7 days duration in a vaccinated dog with normal appetite and energy are often managed symptomatically with a 7 to 10 day observation period. Persistent signs, unilateral discharge, epistaxis, or facial pain warrant advanced imaging. The American College of Veterinary Internal Medicine publishes consensus statements on diagnostic and management approaches for companion animal internal medicine conditions, and these documents provide structured guidance for conditions where evidence is evolving.

Computed tomography is the imaging modality of choice for nasal and sinus disease. It provides superior bony detail, identifies foreign bodies, and allows assessment of the cribriform plate, which is critical for surgical planning and prognostic assessment. Magnetic resonance imaging offers better soft tissue contrast and is preferred when intracranial extension is suspected. Skull radiographs are of limited value and should not be used as a screening test when CT is available.

Rhinoscopy allows direct visualization of the nasal mucosa, identification of foreign bodies and fungal plaques, and targeted biopsy. Anterior rhinoscopy with a rigid scope visualizes the rostral nasal cavity, while retroflexed rhinoscopy through the choanae assesses the caudal aspect. Biopsy samples should be large enough for histopathology and should be obtained from multiple sites because neoplastic lesions may have areas of necrosis or inflammation. The ACVIM consensus statements provide guidance on the appropriate use of these advanced diagnostic techniques.

Initial Stabilization and Triage

The first decision in managing canine upper respiratory disease is whether the patient requires immediate intervention. Upper airway obstruction can progress rapidly, and the physical examination findings that mandate urgent action are specific: stertor at rest, inspiratory effort with visible abdominal component, cyanosis, or collapse. Patients with these findings need oxygen support and sedation before further diagnostic testing.

Partial upper airway obstruction responds to flow-by oxygen and a short-acting sedative that reduces anxiety without suppressing respiratory drive. Patients with complete obstruction, or those that do not improve with medical management, require intubation or tracheostomy. The decision to place a temporary tracheostomy should be made early, not after repeated failed attempts at medical stabilization. Equipment for emergency tracheostomy should be available in every practice that sees brachycephalic dogs.

Thermal stress is a second immediate concern. Dogs with upper respiratory disease often have impaired heat dissipation through panting. Rectal temperature above 40.5°C with respiratory distress warrants active cooling. This is particularly relevant in brachycephalic breeds during warm weather, where heatstroke and upper airway obstruction frequently coexist.

Targeted Diagnostic Testing

When to Test and What to Test For

Not every dog with upper respiratory signs requires advanced diagnostics. Acute onset of mild nasal discharge and sneezing in a vaccinated, otherwise healthy dog can be managed symptomatically with a recheck in 5 to 7 days. Diagnostic testing is indicated when any of the following are present: persistent signs beyond 10 days, unilateral discharge, facial pain or swelling, systemic illness, suspected foreign body, or disease in an immunocompromised or geriatric patient.

The diagnostic sequence follows a logical progression from least to most invasive. Rhinoscopy with biopsy and imaging are reserved for cases where initial testing is unrevealing or where structural disease is suspected. The table below summarizes the available tests and the clinical scenarios that favour each.

Interpreting PCR Results

PCR panels for canine respiratory pathogens are commercially available and typically include canine distemper virus, canine adenovirus type 2, canine parainfluenza virus, canine respiratory coronavirus, Bordetella bronchiseptica, Mycoplasma cynos, and Streptococcus equi subspecies zooepidemicus. The major interpretive challenge is that healthy dogs can carry several of these organizms without clinical disease. A positive PCR result therefore supports, but does not confirm, an infectious aetiology. The result must be interpreted alongside clinical signs, cytology, and response to therapy.

Quantitative PCR with cycle threshold values can help distinguish active infection from low-level carriage, but published cut-offs are not standardized across laboratories. When in doubt, paired acute and convalescent serology or demonstration of the organizm in a sterile site provides stronger evidence. In outbreak situations, sampling multiple affected dogs and comparing strain sequences can identify a common source.

Management by Aetiology

Infectious Disease

Supportive care is the foundation for viral upper respiratory infections. Humidification, gentle nasal cleansing, and appetite support are the mainstays. Antibiotics are not indicated for primary viral disease. They are reserved for dogs with confirmed or strongly suspected bacterial infection, or those with mucopurulent discharge lasting more than 10 days where secondary bacterial rhinitis is likely.

Bordetella bronchiseptica infection is treated with antibiotics selected on the basis of culture and susceptibility where possible. The organizm is intrinsically resistant to some commonly used agents, and susceptibility patterns vary geographically. Mycoplasma cynos is a frequent co-pathogen and is not detected by routine bacterial culture unless specific media are requested. PCR is the most reliable method for detecting this organizm.

Fungal rhinitis, most commonly caused by Aspergillus fumigatus, requires topical or systemic antifungal therapy. The diagnosis is confirmed by rhinoscopic visualization of fungal plaques, positive fungal culture, or serology. CT findings of turbinate destruction and a soft tissue mass within the nasal cavity are supportive. Treatment protocols vary, and current formulary references should be consulted for drug selection and monitoring requirements.

Structural and Inflammatory Disease

Brachycephalic obstructive airway syndrome requires a multimodal approach. Medical management with weight reduction, exercise restriction, and anti-inflammatory therapy addresses clinical signs but does not correct the underlying anatomic abnormalities. Surgical intervention, including staphylectomy, alaplasty, and laryngeal sacculectomy, is indicated when medical management fails or when the patient presents with severe obstruction. The timing of surgery depends on the severity of clinical signs and the owner's ability to comply with long-term management.

Lymphoplasmacytic rhinitis is a diagnosis of exclusion. It is characterized by chronic nasal discharge with histologic evidence of lymphocytic and plasmacytic infiltration in the absence of an identifiable infectious or neoplastic cause. Response to immunosuppressive therapy is variable, and many dogs require long-term management. The prognosis is guarded, and owners should understand that treatment aims to control signs instead of cure the disease.

Neoplasia

Nasal neoplasia is most common in older, large-breed dogs. Adenocarcinoma and chondrosarcoma are the most frequently diagnosed tumors. CT is essential for staging and surgical planning. Treatment options include radiotherapy, surgery, or a combination of both. The choice depends on tumor type, extent of disease, and availability of referral services. Dogs with nasal lymphoma may respond to systemic chemotherapy, and a biopsy is required to make this distinction.

Monitoring and Follow-Up

Patients hospitalized with upper respiratory disease should be monitored for respiratory rate and effort, oxygen saturation, appetite, and hydration status. Worsening inspiratory effort, increased stertor, or development of cyanosis indicates progressive obstruction and warrants reassessment of the treatment plan.

Dogs discharged on medical therapy should be rechecked within 7 to 14 days. Lack of improvement, or deterioration, is an indication for advanced imaging and rhinoscopy. Persistent unilateral discharge, facial deformity, or epistaxis at any point should prompt investigation for neoplasia or fungal disease instead of repeated courses of antibiotics.

Documentation and Communication

The medical record should document the duration and character of nasal discharge, the presence or absence of systemic signs, and the results of each diagnostic test. Photographs of rhinoscopic findings and CT images are valuable for monitoring disease progression and for communication with referral services.

Owner communication should address the expected timeline for improvement, the signs that warrant an earlier recheck, and the financial implications of advanced diagnostics. For chronic conditions, a written management plan that includes medication schedules, recheck intervals, and criteria for escalation of care reduces the risk of treatment failure due to owner confusion.

The decision framework below summarizes the management pathway from initial presentation through definitive diagnosis and treatment.

flowchart TD
    A[Canine upper respiratory signs] --> B{Stable?}
    B -->|No| C[Stabilize: oxygen, sedation, cooling]
    C --> B
    B -->|Yes| D{Acute, mild, vaccinated?}
    D -->|Yes| E[Symptomatic care, recheck 5-7 days]
    E --> F{Improved?}
    F -->|Yes| G[Continue care]
    F -->|No| H[Diagnostic workup]
    D -->|No| H
    H --> I[PCR, radiography, bloodwork]
    I --> J{Diagnosis confirmed?}
    J -->|Yes| K[Targeted treatment]
    J -->|No| L[CT, rhinoscopy, biopsy]
    L --> M[Definitive diagnosis]
    M --> K

Where referral services are unavailable, the general practitioner must decide whether to continue empirical management or to limit diagnostic testing to what is locally possible. In these settings, a trial of therapy with careful documentation of response is acceptable, provided the owner understands the limitations of this approach. The MSD Veterinary Manual provides guidance on the clinical features and management of the specific conditions discussed here, and the ACVIM consensus statements offer evidence-based recommendations for conditions where expert consensus exists.

Complications and Failure Modes

Upper respiratory disease in dogs generally follows a self-limiting course, but specific complications warrant active surveillance. Aspiration pneumonia is the most consequential, occurring when nasal discharge, laryngeal dysfunction, or heavy sedation compromises airway protection. Detect it early through serial thoracic auscultation, monitoring for crackles or increased bronchial sounds, and by tracking respiratory effort and oxygenation. A dog that develops a wet cough, fever, or tachypnoea after initial presentation should have thoracic radiographs performed without delay.

Chronic rhinitis is a second failure mode. It develops when an acute infectious or inflammatory insult damages the nasal mucosa and turbinates, permitting persistent bacterial colonisation. The discriminating feature is duration: signs that fail to resolve after three to four weeks of appropriate therapy warrant re-evaluation instead of repeated antibiotic courses. Imaging findings of turbinate destruction or frontal sinus opacification support the diagnosis.

Sinusitis and mucocele formation occur when ostial obstruction traps secretions. These present with facial asymmetry, epiphora, or pain on palpation over the frontal sinuses. Computed tomography is the most reliable means of confirming the diagnosis and planning surgical intervention.

Systemic spread of infection is uncommon but recognized. Streptococcus equi subspecies zooepidemicus, for example, can produce severe pneumonia and septicemia in addition to upper respiratory signs. The organizm has been identified as a common respiratory pathogen in crowded cat populations, and similar virulence is recognized in dogs. Suspect systemic involvement when a dog with upper respiratory signs develops lethargy, pyrexia, or a rising leukocyte count out of proportion to the local disease.

Common Errors in Diagnostic Reasoning

The most frequent error is treating all nasal discharge as infectious. Serous or clear discharge with sneezing in a vaccinated adult dog often reflects allergic or irritant disease, and empirical antibiotics are neither indicated nor effective. The corrective action is to characterize the discharge, assess chronicity, and reserve antimicrobials for dogs with mucopurulent discharge, fever, or systemic signs.

A second error is overinterpreting PCR results. A positive result for a respiratory pathogen confirms exposure or carriage, not causation. Healthy dogs can harbour organizms without clinical disease, and a negative result does not exclude infection. Interpret PCR in the context of clinical signs, cytology, and response to therapy. The same principle applies to serology, which has limited utility in acute upper respiratory disease.

A third error is failing to examine the oral cavity and oropharynx. Foreign bodies lodged in the nasopharynx or oropharynx can mimic infectious rhinitis, and missing them leads to weeks of ineffective treatment. A thorough sedated oral examination with a laryngoscope should be part of the workup for any dog with acute onset, unilateral discharge, or signs that fail to respond.

A fourth error is delaying imaging in dogs with suspected neoplasia. A middle-aged or older dog with unilateral epistaxis, facial deformity, or progressive signs should not receive repeated courses of antibiotics while a nasal tumor expands. Early computed tomography and biopsy change both prognosis and treatment options.

Limitations of the Evidence and Areas of Expert Disagreement

The evidence base for canine upper respiratory disease is thinner than for feline disease. Much of the infectious disease literature derives from cats, including work on calicivirus and retroviral cofactors, and extrapolation to dogs must be cautious. The role of specific bacterial pathogens in canine infectious tracheobronchitis remains contested, and expert opinion differs on whether Bordetella bronchiseptica is a primary pathogen or an opportunist that follows viral damage.

The value of empirical antimicrobial therapy is similarly debated. Some experts advocate a short course of doxycycline for suspected bacterial involvement, while others argue that antimicrobial stewardship demands cytologic or culture confirmation before treatment. Both positions have merit, and the decision should reflect signalment, severity, and the presence of comorbidities.

There is also disagreement about the utility of intranasal vaccines. They reduce clinical signs but do not prevent infection or shedding, and their use in outbreak settings is supported by some authorities and questioned by others. The ACVIM consensus statements provide a useful synthesis of current opinion, but they do not resolve every point of contention.

Referral, Consultation, and Reporting

Referral to a specialist is warranted when imaging is needed, when endoscopic evaluation is planned, or when a dog fails to respond to appropriate first-line therapy. Dogs with suspected nasal neoplasia, chronic rhinitis requiring biopsy, or structural abnormalities such as choanal stenosis should be referred for computed tomography and rhinoscopy. Specialist consultation is also appropriate for dogs with recurrent aspiration pneumonia or suspected immune-mediated respiratory disease.

Laboratory involvement is indicated for culture and sensitivity testing when empirical therapy has failed, for histopathology of biopsy specimens, and for PCR panels when a specific infectious aetiology is suspected. The MSD Veterinary Manual offers guidance on the indications for each test and the interpretation of results.

Regulatory reporting is rarely required for canine upper respiratory disease. Canine influenza is a reportable disease in some jurisdictions, and veterinarians should be aware of local requirements. The WOAH terrestrial animal health standards describe international reporting obligations for diseases with trade implications, and the AVMA practice resources provide guidance on state and federal reporting requirements. When in doubt, contact the relevant veterinary authority before releasing a dog from isolation.

Frequently Asked Questions

How Should I Prioritize Testing When the Owner Has a Limited Diagnostic Budget?

Start with thoracic radiographs and a complete blood count if the dog has fever, lethargy, or abnormal lung sounds, since these findings most change immediate management. If the presentation is classic acute infectious tracheobronchitis in an otherwise stable dog, a therapeutic trial with strict rest and recheck in 7 to 10 days is reasonable before advanced testing. When PCR panels are affordable, prioritize them before serology because they detect active shedding. Reserve advanced imaging for cases with neurologic signs, suspected foreign body, or mass lesions. Document the financial discussion in the record and state clearly which differentials remain untested. The MSD Veterinary Manual provides guidance on cost-conscious diagnostic planning for common respiratory presentations.

What Do I Do When Reverse Transcriptase PCR Testing Is Unavailable?

Viral isolation and paired serology remain acceptable alternatives for confirming canine respiratory virus infections, though results take longer and may not influence acute management. In practice, treat empirically based on signalment, exposure history, and clinical pattern. A dog with acute cough, serous ocular discharge, and recent boarding exposure most likely has infectious tracheobronchitis regardless of confirmatory testing. If clinical signs progress despite supportive care, pursue bacterial culture from transtracheal wash or bronchoalveolar lavage. Remember that negative PCR does not exclude infection, so clinical judgment governs treatment decisions. The ACVIM consensus statements offer frameworks for diagnostic reasoning when advanced testing is limited.

How Does My Approach Change for Brachycephalic Breeds?

Brachycephalic dogs present a special diagnostic challenge because conformational disease can mimic or coexist with infectious and inflammatory conditions. Always assess for stertor, exercise intolerance, and heat sensitivity before attributing signs to infection. Sedated oral and nasal examination is essential to evaluate stenotic nares, elongated soft palate, and everted laryngeal saccules. If a brachycephalic dog presents with acute severe respiratory distress, prioritize stabilization over extensive diagnostics. Manage these patients with the expectation that upper airway obstruction may require surgical correction even after medical issues resolve. Owners should understand that recurrent infections in these breeds often reflect underlying anatomic compromise instead of repeated exposure.

What Records Should I Keep for a Dog with Recurrent Upper Respiratory Disease?

Maintain a problem list that tracks each episode with date, clinical signs, treatments used, and response. Record vaccination status, travel history, and boarding exposure at each visit. Document imaging findings with serial comparison when possible, and archive bronchoscopy images or video when performed. Note any breed-specific conformational issues and their progression over time. If you suspect a congenital or hereditary component, record pedigree information and discuss this with the owner. For cases involving potential zoonotic or reportable pathogens, follow WOAH terrestrial animal health standards for notifiable disease reporting. Clear documentation supports future clinical decisions and protects against liability if complications arise.

How Should I Explain Chronic Upper Respiratory Disease to a Frustrated Owner?

Use plain language that separates the diagnosis from the prognosis. Explain that the nose and throat have limited ways to respond to many different insults, so similar signs can have different causes. Show the owner the diagnostic plan as a stepwise process instead of a single test. Emphasize that some conditions are managed instead of cured, and set realistic expectations about the timeline. Provide written instructions for home care, including environmental changes such as humidification and reducing smoke exposure. The AVMA practice resources include client communication tools that can support these conversations. Offer a recheck schedule and invite the owner to call with concerns between visits.

When Should I Suspect a Noninfectious Cause Despite Positive PCR Results?

Positive PCR results confirm the presence of a pathogen but do not prove causation. Suspect a primary structural or inflammatory process when clinical signs persist beyond the expected course of infection, when response to appropriate antimicrobial therapy is incomplete, or when signs recur shortly after treatment ends. Consider foreign bodies, nasal neoplasia, and chronic rhinitis in dogs with unilateral discharge, facial deformity, or bleeding. Perform imaging and rhinoscopy when signs are asymmetric or progressive. Coinfection is common, so a positive result for one organizm does not exclude concurrent disease. The MSD Veterinary Manual emphasizes that diagnostic test results must always be interpreted within the full clinical context.

Related Clinical & Scientific Guides

• Feline Hepatic Lipidosis: Nutritional and Medical Management
• Canine Respiratory Infection: Diagnostic Approach and Treatment
• Canine Respiratory Virus: Diagnostic and Management Considerations

References and Further Reading

• Calicivirus Infection in Cats.. 2022.
• Stachybotrys chartarum: cause of human disease or media darling?. 2003.
• Development of clinical disease in cats experimentally infected with feline immunodeficiency virus.. 1994.
• Infectious diseases in large-scale cat hoarding investigations.. 2014.
• Equine Influenza.. 2022.
• ACVIM Consensus Statements. Journal of Veterinary Internal Medicine.
• MSD Veterinary Manual, Professional Edition. MSD Veterinary Manual.
• American Veterinary Medical Association Practice Resources. American Veterinary Medical Association.
• WOAH Terrestrial Animal Health Code. WOAH.

Related Articles

• Canine Vestibular Syndrome: Differential Diagnosis and Management
• Canine Lower Respiratory Disease: Diagnostic and Management Strategy
• Canine Lung Disease: Differential Diagnosis and Diagnostic Approach
• Canine Exocrine Pancreatic Insufficiency: Diagnosis and Management
• Canine Respiratory Virus: Diagnostic and Management Considerations

This article is educational professional reference material for veterinary audiences. It is not a substitute for veterinary diagnosis, individual clinical judgment, current product labeling, or applicable regulatory requirements.