Differential Diagnosis of Acute Bovine Respiratory Disease in Feedlot Cattle

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

Key Takeaways

• Acute Bovine Respiratory Disease (BRD) is primarily caused by bacterial and viral pathogens of the bovine respiratory complex, including Mannheimia hemolytica, Pasteurella multocida, Histophilus somni, BHV-1, PI3V, BRSV, and BVDV, leading to infectious bronchopneumonia characterized by fever, depression, reduced intake, and tachypnea.
• Differential diagnoses extend beyond infectious causes to include metabolic derangements (e.g., ruminal acidosis with endotoxemia), cardiac conditions (e.g., myocardial disease, pericarditis), and environmental factors (e.g., heat stress, dust inhalation), which can mimic BRD through overlapping clinical signs like tachypnea and depression.
• A structured diagnostic framework is essential, beginning with inexpensive, non-invasive tools such as rectal temperature, thoracic auscultation, and ultrasound, progressing to more complex diagnostics like complete blood counts, acute phase proteins, and nasopharyngeal swabs for pathogen detection via PCR.
• Thoracic ultrasonography is a critical point-of-care tool for detecting pulmonary consolidation, pleural effusion, and abscessation, aiding in treatment decisions and distinguishing BRD from conditions like interstitial pneumonia or congestive heart failure.
• BVDV, particularly noncytopathic BVDV 1b, is a significant consideration as it can present with respiratory signs and persistently infected (PI) animals act as continuous viral reservoirs, necessitating investigation for PI status in affected calves.
• Response to therapy and progression over 24-48 hours are critical differentiators; failure to improve with initial treatment warrants reassessment for non-BRD causes or complications such as pulmonary abscessation or fibrinous pleuritis.

Acute bovine respiratory disease (BRD) remains the most common cause of morbidity and mortality in feedlot cattle during the first weeks after arrival. The clinical syndrome of fever, depression, reduced feed intake, and abnormal respiratory effort is familiar to every feedlot practitioner, yet the differential diagnosis extends well beyond the classic bacterial and viral pathogens of the bovine respiratory complex. This article provides a structured diagnostic framework for the practicing veterinarian evaluating acute respiratory signs in feedlot cattle. It distinguishes BRD from metabolic, cardiac, toxic, and environmental conditions that can mimic or complicate the presentation, and it outlines the diagnostic workup needed to reach a defensible clinical diagnosis.

The reader is assumed to be a qualified veterinarian working in feedlot or stocker practice. The content emphasizes decision criteria, diagnostic reasoning, and interpretation of clinical and laboratory findings. Treatment protocols are excluded by design. Where the evidence base is limited or contested, that uncertainty is stated directly. Regional differences in disease prevalence, regulatory requirements, and production systems are noted where relevant, and the reader should consult USDA APHIS animal health information and WOAH terrestrial animal health standards for jurisdiction-specific surveillance and reporting obligations.

At a Glance

The Pathophysiologic Basis of Differential Diagnosis

Acute respiratory signs in feedlot cattle arise from a limited set of pathophysiologic mechanisms. The most common is infectious bronchopneumonia, in which viral or bacterial pathogens colonize the lower airways, incite neutrophilic inflammation, and produce fibrinous exudation and consolidation. The host response, particularly the release of proinflammatory cytokines and reactive oxygen species, contributes substantially to tissue damage. The oxidative burden in pulmonary inflammation is well documented in experimental models of acute lung injury, and the balance between oxidant production and antioxidant capacity influences the severity of epithelial and endothelial injury.

A second mechanism is noninfectious pulmonary inflammation. Inhalation of dust, ammonia, or other noxious gases can trigger airway irritation and bronchoconstriction. Heat stress produces tachypnea through thermoregulatory panting instead of pulmonary pathology. Cardiac disease causes respiratory signs through impaired oxygen delivery and pulmonary venous congestion. Metabolic derangements, particularly acidosis, produce tachypnea and depression through systemic acid-base disturbance instead of primary pulmonary pathology.

The diagnostic challenge is that these mechanisms overlap clinically. A calf with ruminal acidosis may present with fever, depression, and tachypnea that is indistinguishable from early BRD on physical examination alone. A calf with myocardial disease may have crackles on thoracic auscultation that mimic pneumonia. The differential diagnosis therefore rests on a systematic evaluation that integrates history, physical examination, targeted diagnostics, and response to therapy.

Viral Pathogens and the BRD Complex

The viral component of BRD is dominated by bovine herpesvirus 1, parainfluenza 3 virus, bovine respiratory syncytial virus, and bovine viral diarrhea virus (BVDV). These viruses damage the respiratory epithelium, impair mucociliary clearance, and predispose to secondary bacterial pneumonia. BVDV deserves particular attention in the differential diagnosis because it can present with respiratory signs as a primary complaint, and because persistently infected (PI) animals serve as a continuous source of viral shedding within a pen.

Diagnostic laboratory data from the United States demonstrate that BVDV subgenotypes are not evenly distributed. In a survey of 131 BVDV-positive diagnostic accessions, the noncytopathic biotype predominated, and subgenotype 1b was more common than 1a or 2a. All three subgenotypes were identified in both persistently infected cattle and in respiratory disease submissions. A separate study of stocker calves with acute respiratory disease confirmed that noncytopathic BVDV 1b was the predominant subtype isolated from sick calves, including one persistently infected calf that shed virus repeatedly over time without seroconversion to BVDV 1a or 2. These findings have practical implications for vaccine selection and diagnostic testing. The genetic distance between field strains and vaccine strains is relevant when interpreting vaccine failure, and the practitioner should consider BVDV subgenotype when choosing diagnostic assays and interpreting results.

The presence of BVDV in a respiratory disease outbreak does not prove causation. BVDV is immunosuppressive, and coinfection with bacterial pathogens is common. The diagnostic workup should therefore include testing for the full panel of respiratory pathogens, not BVDV alone. Detection of BVDV in a sick calf warrants investigation for PI status, because a single PI animal can perpetuate viral transmission within a pen for the entire feeding period.

The Role of Host Immunity and Individual Variation

The clinical expression of respiratory disease varies widely among calves exposed to the same pathogens. Host factors including age, nutritional status, prior vaccination, and genetic background influence susceptibility and severity. The immune response to respiratory pathogens is coordinated by antigen-presenting cells, particularly dendritic cells, which capture antigen in the respiratory tract and present it to T cells in regional lymph nodes. Studies in cattle have identified phenotypically distinct populations of dendritic cells in afferent lymph that differ in their ability to stimulate T cell responses. These differences may contribute to variation in vaccine responsiveness and disease susceptibility among individuals.

For the practitioner, this means that a single diagnostic test result must be interpreted in the context of the individual animal and the group. A calf with a high fever and severe depression may have minimal lung pathology on ultrasound, while a calf with mild clinical signs may have extensive consolidation. The differential diagnosis is not a checklist to be applied mechanically. It is a reasoning process that weighs the probability of each condition based on the available evidence.

Diagnostic Reasoning and the Workup

The diagnostic workup for acute respiratory disease in feedlot cattle proceeds from the inexpensive and noninvasive to the more complex. Rectal temperature, respiratory rate and effort, thoracic auscultation, and ultrasound examination of the lung fields provide the initial data. Thoracic ultrasound is particularly useful for detecting consolidation, pleural effusion, and abscessation, and it can guide the decision to treat or to cull. Complete blood count and serum biochemistry can identify leukocytosis, left shift, and markers of inflammation or metabolic derangement. Nasopharyngeal swabs or bronchoalveolar lavage samples submitted for pathogen detection by PCR or culture can identify the specific infectious agents involved.

The interpretation of diagnostic tests requires attention to timing. Viral detection by PCR does not distinguish between live virus, dead virus, or vaccine virus. Bacterial culture results may reflect commensal flora instead of the causative pathogen. Serology requires paired samples to demonstrate a rising titer, which is impractical in an acute outbreak. The practitioner should therefore combine diagnostic testing with clinical response to therapy and, where mortality occurs, necropsy with histopathology and culture of lung lesions.

The MSD Veterinary Manual provides a peer-reviewed reference for the clinical features and diagnostic approach to respiratory disease in cattle, and the AVMA practice resources offer guidance on professional standards and diagnostic decision-making. These sources are useful starting points for the practitioner seeking to confirm or refine a diagnostic plan.

Structured Differential Prioritization for Acute Respiratory Signs

The diagnostic workup of an acutely dyspneic feedlot animal proceeds from a small set of questions. Is the problem primarily respiratory, cardiovascular, metabolic, or physical? Within the respiratory category, is the lesion upper airway, lower airway, or pleural? Does the animal have a contagious process that threatens penmates, or an individual medical problem? The order in which these questions are answered determines how quickly a working diagnosis emerges and how safely the case is managed.

Step 1: Triage and Immediate Assessment

The first decision is whether the animal requires immediate intervention before a complete examination. A calf with severe respiratory distress, open-mouth breathing, cyanosis, or recumbency needs stabilization in parallel with diagnostic assessment. In this situation, the physical examination is abbreviated to the parameters that distinguish immediate threats: respiratory rate and effort, heart rate and rhythm, mucous membrane color, and the presence or absence of a pulse deficit.

Auscultation of the trachea and both lung fields is performed before any handling that could exacerbate distress. The presence of referred upper airway sounds, which are loudest over the trachea and diminish over the peripheral lung fields, suggests an upper airway obstruction. Harsh bronchial tones with crackles or wheezes over the cranioventral lung fields support a bronchopneumonia. Absent or markedly reduced lung sounds dorsally, with normal sounds ventrally, raise suspicion for pneumothorax or a space-occupying pleural lesion.

Step 2: Physical Examination Findings That Separate the Major Categories

The physical examination is the primary tool for prioritizing differentials. Table 1 summarizes the findings that separate the major diagnostic categories in an acutely dyspneic feedlot animal.

The combination of fever, mucopurulent nasal discharge, and cranioventral lung sounds is strongly supportive of BRD. The absence of fever does not exclude BRD, particularly in animals that have been treated previously or are in the later stages of disease. Cardiac failure is distinguished by the presence of jugular distension, dependent edema, and auscultable murmurs or arrhythmias. Upper airway obstruction produces stridor that is audible without a stethoscope and is often positional. Metabolic disease typically produces neurologic signs in addition to tachypnea, and the lung fields auscult normally.

Step 3: Ancillary Testing and the Point-of-Care Toolbox

Point-of-care testing is selected based on the differentials that remain after physical examination. The most useful tools in feedlot practice are thoracic ultrasonography, pulse oximetry, and blood gas analysis where available. Thoracic ultrasonography is particularly valuable because it detects pleural effusion, pulmonary consolidation, and abscessation with greater sensitivity than auscultation alone. A normal pleural surface appears as a thin echogenic line with reverberation artifact. Consolidation appears as hypoechoic tissue with air bronchograms. Pleural effusion appears as an anechoic collection dorsal to the lung.

Pulse oximetry provides a rapid estimate of oxygenation but is unreliable in animals with poor peripheral perfusion, which includes many severely affected calves. Blood gas analysis, when available, distinguishes hypoxemic respiratory failure from ventilation-perfusion mismatch and identifies metabolic acid-base disturbances that may be the primary problem.

Step 4: The Differential Prioritization Framework

Table 2 presents a structured framework for prioritizing differentials based on the dominant clinical presentation. The framework assumes that physical examination has been completed and that the animal is stable enough for further assessment.

The framework is applied iteratively. An animal that fails to respond to initial treatment for the first-tier differential is re-examined with the second-tier differentials in mind. For example, a calf treated for BRD that remains febrile and dyspneic after 48 hours should be re-evaluated for complications such as pulmonary abscessation, fibrinous pleuritis, or extension to the pericardium.

Step 5: Documenting the Workup

Documentation of the respiratory disease workup serves two purposes: it supports treatment decisions for the individual animal, and it provides the data needed to evaluate pen-level and cohort-level disease patterns. Each record should include the animal identification, date and time of examination, rectal temperature, heart rate, respiratory rate, body condition score, and a standardized description of lung auscultation findings. The use of a numeric lung score, such as a 0 to 4 scale where 0 is normal and 4 is severe bilateral involvement, improves consistency between examiners.

Photographs of nasal discharge, ocular discharge, and thoracic ultrasound images are valuable additions to the record. They allow a second opinion from a colleague or a specialist without transporting the animal. The record should also note the differentials considered, the tests performed, and the rationale for the final working diagnosis. This documentation becomes particularly important when a case is unusual, fails to respond to treatment, or involves a suspected foreign animal disease.

Step 6: When to Escalate the Workup

Most feedlot respiratory cases are managed on the basis of physical examination and response to treatment. Escalation to advanced diagnostics is indicated when an animal fails to respond to appropriate first-line therapy, when the physical examination findings are atypical for BRD, when multiple animals in a cohort present with unusual signs, or when a foreign animal disease is suspected. In these situations, consultation with a veterinary diagnostic laboratory is appropriate. The laboratory can advise on sample selection, transport media, and testing strategies. The USDA APHIS animal health information portal provides guidance on reportable disease suspicion and submission pathways.

The decision to escalate also depends on the production system. A commercial feedlot with high throughput may elect to treat empirically and monitor response at the pen level. A purebred operation or a research herd may justify more intensive individual diagnostics. The MSD Veterinary Manual, Professional Edition provides species-specific guidance on diagnostic techniques and interpretation that can support these decisions. The correct choice is the one that matches the clinical risk, the economic context, and the capacity of the local diagnostic infrastructure.

Recognized Complications and Early Detection

The most consequential failure mode in managing acute respiratory disease in feedlot cattle is delayed recognition of a non-BRD primary process. Interstitial pneumonia, congestive heart failure, and metabolic disease can all present with tachypnoea, depression, and reduced intake, and each worsens when treated empirically as bacterial bronchopneumonia.

Interstitial pneumonia. Acute interstitial pneumonia (AIP) typically appears 10 to 45 days after arrival, often in cattle consuming high-concentration diets. The hallmark is severe expiratory dyspnoea with a normal or minimally elevated temperature, and auscultation reveals diffuse crackles instead of the cranioventral consolidation of bronchopneumonia. Hypoxemia is often profound. The discriminating finding is the absence of a favourable response to antimicrobial therapy within 48 hours combined with progressive respiratory effort. Thoracic ultrasonography shows diffuse B-lines without the focal consolidation typical of bacterial pneumonia.

Congestive heart failure. Pulmonary hypertension and right heart failure, including brisket disease and high-altitude disease, produce tachypnoea, jugular distension, and ventral edema. The key error is attributing the respiratory effort to pneumonia when the primary pathology is cardiac. Auscultation may reveal a murmur or accentuated second heart sound, and the respiratory rate fails to respond to bronchodilators or antimicrobials. Ultrasonography can identify pleural effusion, ascites, and hepatic venous distension.

Metabolic disease. Severe ketosis and pregnancy toxemia can produce tachypnoea through acidosis, but the respiratory pattern is typically deep and regular instead of labored. Hypocalcemia in older cattle may cause recumbency with apparent respiratory distress that is actually positional. A rapid response to calcium therapy in the appropriate clinical context confirms the diagnosis.

Early detection depends on systematic recheck of all treated animals at 24 and 48 hours, with explicit criteria for treatment failure: persistent fever, worsening respiratory effort, or new onset of edema or dyspnoea at rest.

Common Diagnostic Errors and Corrective Action

The most common error made by less experienced clinicians is anchoring on the arrival history. A calf that is treated for BRD on day 3 and fails to improve is often retreated for BRD on day 5 instead of reassessed for AIP or cardiac disease. The corrective action is a structured recheck that includes temperature, respiratory rate and effort, auscultation, and ultrasound before any second treatment is given.

A second error is over-reliance on a single diagnostic test. A negative nasopharyngeal swab PCR does not exclude bacterial pneumonia, and a positive result for a viral pathogen does not confirm that the virus is the cause of the current disease. The diagnostic workup must integrate clinical findings, imaging, and laboratory results.

Limitations of the Evidence and Divergent Expert Opinion

The evidence base for BRD differential diagnosis is constrained by several factors. Diagnostic laboratory data are biased toward severe or fatal cases, and the distribution of pathogens in such submissions may not reflect the causes of mild disease in the live pen. For example, laboratory accessions show that bovine viral diarrhea virus subgenotypes, particularly BVDV1b, are commonly identified in calves with respiratory disease, but the causal role of BVDV in acute respiratory outbreaks remains debated because many infections are subclinical and concurrent bacterial pathogens are often present Fulton et al., 2002. The same laboratory data show that noncytopathic BVDV biotypes predominate and that most isolates are not genetically similar to vaccine strains, which complicates interpretation of vaccine failure Fulton et al., 2005.

Expert opinion diverges on several practical points. The value of thoracic ultrasonography as a routine screening tool is accepted by many feedlot practitioners but not universally implemented, and the threshold for classifying a calf as a treatment failure varies between operations. The role of viral diagnostics in guiding therapy is similarly contested. Some clinicians argue that identifying a specific viral pathogen changes management, while others maintain that the treatment decision is driven by clinical severity and bacterial risk regardless of viral status.

The evidence for the pathophysiology of interstitial pneumonia is incomplete. The condition is likely multifactorial, and the relative contributions of dietary factors, toxins, and viral infection remain unclear. The MSD Veterinary Manual provides a general reference for the clinical features of these conditions, but specific incidence data and controlled trials are lacking MSD Veterinary Manual.

Escalation, Referral, and Regulatory Reporting

Escalation is warranted when a case fails to respond to appropriate therapy within 48 hours, when the clinical picture is inconsistent with BRD, or when a condition poses a risk to the rest of the group. Referral to a veterinary teaching hospital or a specialist in internal medicine is appropriate for cases requiring advanced imaging, bronchoscopy, or intensive monitoring that cannot be provided on farm.

Laboratory involvement is indicated for outbreak investigation, for cases with unusual clinical features, and for confirmation of a suspected pathogen when the result will change management. Necropsy with histopathology, bacterial culture, and viral PCR is the most informative approach for fatal cases and should be performed promptly to avoid autolysis.

Regulatory reporting obligations vary by jurisdiction. Foreign animal diseases that cause respiratory signs, including malignant catarrhal fever and contagious bovine pleuropneumonia, must be reported to the relevant animal health authority. The World Organization for Animal Health maintains international standards for disease notification and surveillance, and veterinarians should be familiar with the reporting requirements in their region WOAH terrestrial animal health standards. National programs and reporting pathways are described by the relevant government agency, such as the USDA Animal and Plant Health Inspection Service in the United States USDA APHIS animal health information.

When a case is escalated, the referring veterinarian should provide a complete record including arrival date, treatment history, temperature curve, ultrasound findings, and laboratory results. This documentation allows the receiving clinician to distinguish treatment failure from misdiagnosis and to plan the next diagnostic step without repeating the workup.

Frequently Asked Questions

How Do I Prioritize Differentials When Point-of-Care Testing Is Unavailable?

When thoracic ultrasonography, blood gas analysis, or acute-phase protein assays are not available, return to the physical examination and response to initial therapy. Serial temperature assessment, thoracic auscultation, and nasal discharge character provide the most accessible separation. A calf with a temperature above 40.0°C, mucopurulent nasal discharge, and auscultable cranioventral lung sounds is far more likely to have bacterial bronchopneumonia than cardiac or metabolic disease. Response to a labeled antimicrobial within 48 to 72 hours supports a bacterial component. If fever persists without localizing signs, broaden the differential to include viral pathogens such as bovine viral diarrhea virus, which appears in both respiratory and multisystemic presentations in diagnostic laboratory accessions. Document the examination findings and the treatment response explicitly so a subsequent clinician can reconstruct the reasoning.

What Is the Minimum Ancillary Testing Battery for a Diagnostic Workup?

A practical minimum battery includes a complete blood count, serum fibrinogen, and thoracic ultrasonography. The complete blood count identifies leukopenia or leukocytosis and left shift, which support infectious disease. Fibrinogen elevation is a nonspecific acute-phase response but adds supportive evidence for inflammation. Thoracic ultrasonography detects cranioventral consolidation, pleural effusion, and abscessation that auscultation misses. When viral involvement is suspected, add a nasopharyngeal swab for PCR panel testing and paired serology. For calves that die, lung culture and histopathology remain the reference standard. The diagnostic laboratory data on bovine viral diarrhea virus subgenotypes show that PCR-based subtyping distinguishes vaccine-related strains from field strains, which matters when investigating vaccine failure. Consult the MSD Veterinary Manual for interpretation of specific laboratory parameters.

How Does the Differential Approach Change for Dairy Calves or Adult Cattle?

The framework shifts with age and production system. Dairy calves housed individually have lower infectious pressure but higher risk of aspiration pneumonia, so esophageal dysfunction and improper bottle feeding enter the differential earlier. Adult dairy cattle with acute respiratory signs require stronger consideration of interstitial pneumonia, pulmonary thromboembolism secondary to metritis or mastitis, and congestive heart failure from valvular disease. Feedlot cattle concentrate viral and bacterial pathogens within cohorts, making bovine respiratory disease the highest-priority diagnosis. Adult beef cattle on pasture present a different challenge: metabolic disease, bloat with secondary aspiration, and plant toxicities become more plausible. The FAO animal production guidance emphasizes that production system context determines disease prevalence and therefore diagnostic priority.

What Records Should I Keep to Support a Defensible Diagnostic Workup?

Record the signalment, arrival date, days on feed, and treatment history for every affected animal. Document the physical examination findings at first assessment, including temperature, respiratory rate and effort, thoracic auscultation findings, and nasal or ocular discharge. Record the differential list with the leading diagnosis stated explicitly. Note which ancillary tests were performed, the results, and how those results changed the prioritization. Record the treatment administered, the response at recheck, and the final outcome. For mortality cases, document necropsy findings and laboratory results. This record supports both regulatory review and retrospective analysis of diagnostic accuracy. The AVMA practice resources provide guidance on medical record content and retention that applies to food animal practice.

When Should I Suspect a Notifiable or Reportable Disease instead of BRD?

Suspect a reportable disease when clinical signs deviate from the expected BRD pattern. High morbidity with rapid progression, severe dyspnea without cranioventral consolidation, neurologic signs accompanying respiratory disease, or mortality that exceeds the expected case fatality rate all warrant escalation. Hemorrhagic nasal discharge, widespread subcutaneous emphysema, or sudden death in multiple animals should trigger immediate investigation. Consult the WOAH terrestrial animal health standards for the current list of notifiable diseases and the USDA APHIS livestock disease information for national reporting requirements. When in doubt, contact the state or federal veterinary authority before initiating extensive diagnostics, because sample collection and movement restrictions may be regulated.

How Do I Explain the Diagnostic Uncertainty to a Producer or Farm Manager?

Frame the discussion around probabilities and the value of sequential information. Explain that acute respiratory disease in feedlot cattle has several possible causes and that the initial examination narrows but rarely eliminates all alternatives. Describe the diagnostic plan in stages: immediate assessment, targeted testing, response to therapy, and escalation if the response is inadequate. Be explicit about the cost of each diagnostic step and what information it adds. A producer who understands that a negative viral PCR panel rules out certain pathogens while a positive bacterial culture guides antimicrobial selection is more likely to authorize the testing. Acknowledge that some cases resolve without a definitive etiologic diagnosis and that this is acceptable when the animal recovers and the group remains stable. The MSD Veterinary Manual offers client-oriented summaries that can support these conversations.

Related Clinical & Scientific Guides

• Rumen Health Assessment in Dairy Cows: Clinical and Subclinical Indicators
• Mastitis Control Programs in Dairy Herds: Monitoring and Prevention
• Swine Nutrition and Health: Feed-Related Disease Diagnosis

References and Further Reading

• Bovine viral diarrhea virus (BVDV) subgenotypes in diagnostic laboratory accessions: distribution of BVDV1a, 1b, and 2a subgenotypes.. 2005.
• Bovine viral diarrhea virus (BVDV) 1b: predominant BVDV subtype in calves with respiratory disease.. 2002.
• Identification of two distinct populations of dendritic cells in afferent lymph that vary in their ability to stimulate T cells.. 1997.
• Study on the Pulmonary Delivery System of Apigenin-Loaded Albumin Nanocarriers with Antioxidant Activity.. 2017.
• The ratio of oxidative phosphorylation complexes I-V in bovine heart mitochondria and the composition of respiratory chain supercomplexes.. 2001.
• Smartphone-Based Electrochemical Immunoassay for Point-of-Care Detection of SARS-CoV-2 Nucleocapsid Protein.. 2022.
• USDA APHIS Animal Health Information. USDA APHIS.
• FAO Animal Production and Health. FAO.
• MSD Veterinary Manual, Professional Edition. MSD Veterinary Manual.

Related Articles

• Differential Diagnosis of Cough in Feedlot Cattle: BRD vs. Other Respiratory Conditions
• Bovine Respiratory Disease Vaccine Selection: A Comparative Guide
• Differential Diagnosis of Nervous Signs in Cattle: From Metabolic to Infectious
• Bovine Respiratory Disease Prevention: Vaccination and Management Strategies
• Differential Diagnosis of Abortion in Dairy Cattle: Infectious and Non-Infectious Causes

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.