Veterinary Medicine

Clinical Examination and Diagnosis

Topics covered:

Lesson 1: Clinical examination of the individual animal Lesson 2: Making a diagnosis Lesson 3: Making a decision on therapeutics Lesson 4: Assessing the prognosis Lesson 5: Examination of the herd

Clinical examination of the individual animal

Learning Objectives

By the end of this module, students should be able to:

  • Explain the importance and principles of clinical examination in veterinary practice.
  • Systematically approach the examination of an animal to gather accurate diagnostic information.
  • Demonstrate appropriate handling and restraint of different species during examination.
  • Recognize normal vs. abnormal findings in different body systems.
  • Record findings clearly and logically in clinical records.
1. Introduction

Clinical examination is the cornerstone of veterinary diagnosis.

The Purpose is to:

  • Detect deviations from normal health.
  • Establish a clinical diagnosis.
  • Guide further diagnostic tests.
  • Monitor response to treatment.

This process requires knowledge, skill, observation, and systematic approach.

2. General Principles
  • Safety first: Ensure safety of examiner, assistants, and animal.
  • Restraint: Species-specific (halters, crush, stocks, sedation if needed).
  • Environment: Quiet, well-lit, minimal disturbance.
  • Systematic approach: Prevents missing key findings.
  • Compare: Abnormal findings with contralateral/normal structures.
3. Steps of the Clinical Examination

A. History Taking (Anamnesis)

  • Owner/handler interview.
  • Identify: age, sex, breed, use.
  • Chief complaint: onset, duration, progression.
  • Past medical history: vaccination, deworming, diseases, treatments.
  • Feeding and management practices.

B. General Examination

  • Demeanor & Behavior: Bright, alert, responsive, dull, aggressive, depressed.
  • Body Condition Score (BCS): Assess fat/muscle reserves.
  • Posture & Gait: Standing, lying, lameness, ataxia.
  • Skin & Coat: Hair quality, alopecia, lesions, ectoparasites.
  • Mucous Membranes: Color, moisture, capillary refill time.

Vital Signs

  • Temperature – species-specific normal ranges.
  • Pulse/Heart Rate – rate, rhythm, quality.
  • Respiratory Rate – effort, rhythm, abnormal sounds.

C. Systematic Examination (Head-to-tail approach)

Head & Neck

  • Eyes: discharge, cornea, conjunctiva.
  • Nose: discharge, airflow, symmetry.
  • Mouth: teeth, tongue, oral mucosa.
  • Ears: position, discharge, parasites.
  • Lymph nodes: mandibular, prescapular, parotid.

Thorax

  • Heart: auscultation (murmurs, rhythm), palpation.
  • Lungs: auscultation, percussion.
  • Respiratory movements: symmetry, effort.

Abdomen

  • Inspection: contour, distension.
  • Palpation: superficial/deep, organ size.
  • Auscultation: gut sounds.
  • Percussion: fluid, tympany.

Urogenital System

  • External genitalia: discharge, swelling, lesions.
  • Mammary glands/udder: symmetry, heat, pain, milk quality.
  • Rectal examination (large animals): reproductive tract, bladder, GI tract.

Musculoskeletal System

  • Limb symmetry, swelling, pain.
  • Joints: mobility, crepitus, heat.
  • Gait analysis.

Nervous System

  • Mentation.
  • Cranial nerves.
  • Reflexes, coordination.

D. Special Examinations

  • Species-specific focus (e.g., rumen in cattle, hoof in horses, wings in poultry).
  • Diagnostic sampling (blood, urine, feces, milk).


Making a Diagnosis

After a thorough examination of the individual animal, the veterinarian should follow the following steps to make a diagnosis:

Formulating a Problem List
  • Record observed abnormalities: Example: fever, nasal discharge, coughing, reduced appetite.
  • Differential Diagnosis
    Develop a list of possible conditions that could explain the observed signs. Example: for coughing in a calf – pneumonia, lungworm, or inhalation of foreign material.
Diagnostic Testing
  • Use laboratory and imaging tools to narrow down possibilities.
  • Tests include blood work, fecal analysis, radiography, ultrasonography, microbiology, and biopsy.
  • Good diagnostics support but never replace careful clinical observation.
Final (Definitive) Diagnosis
  • Integrate history, clinical signs, and test results to arrive at the most probable explanation.
  • Sometimes only a “tentative diagnosis” is possible, guiding treatment and monitoring.
Types of Diagnosis
  • Tentative Diagnosis – based on clinical signs and history before lab results.
  • Differential Diagnosis – list of possible diseases considered.
  • Definitive Diagnosis – confirmed with clinical, lab, or post-mortem evidence.
  • Prognosis – prediction of disease outcome (good, guarded, poor).
Principles of Good Diagnosis
  • Always approach cases systematically.
  • Avoid tunnel vision - don’t jump to conclusions based on one sign.
  • Use both clinical reasoning and diagnostic tools.
  • Consider herd-level implications in production animals.
  • Keep records clear and logical.


Making a Decision on Veterinary Therapeutics

After a diagnosis has been made, the next critical step in veterinary practice is deciding on the therapeutic approach. This decision must balance the health and welfare of the animal, public health, client expectations, and legal/ethical responsibilities of the veterinarian.

Key Considerations in Therapeutic Decision - Making
  • Confirm the Diagnosis: Treatment decisions should be based on the most accurate diagnosis possible. If the diagnosis is uncertain, consider supportive care while conducting further tests.
  • Nature of the Condition
    • Acute vs. Chronic: Acute infections may require urgent treatment; chronic cases may need long-term management.
    • Reversible vs. Irreversible: Some conditions allow curative therapy, others only palliative or supportive care.
    • Individual vs. Herd/Population: One sick pet vs. herd health approach in livestock.
Therapeutic Options
  • Specific Therapy: Directly targets the cause (e.g., antibiotics for bacterial infection, dewormers for parasites).
  • Symptomatic Therapy: Relieves signs but not the underlying cause (e.g., pain relief, anti-inflammatories).
  • Supportive Therapy: Maintains vital functions (e.g., fluids, electrolytes, nutritional support).
  • Surgical or Mechanical Intervention: Removal of tumors, repair of fractures, drainage of abscesses.
Drug Selection
  • Efficacy: Is the drug proven effective for this condition and species?
  • Spectrum of Activity: Broad vs. narrow spectrum antimicrobials.
  • Safety: Consider species-specific sensitivity, age, pregnancy, lactation.
  • Withdrawal Periods: Critical in food animals to prevent drug residues in milk, meat, eggs.
  • Cost and Availability: Treatment must be practical for the client.
Route and Method of Administration
  • Oral, injectable, topical, intramammary, intrauterine, etc.
  • Consider animal size, temperament, and ease of administration.
Monitoring and Follow-up
  • Evaluate the animal’s response to therapy.
  • Adjust treatment if there is no improvement.
  • Record all treatments accurately for continuity of care and legal purposes.
Ethical and Legal Responsibilities
  • Antimicrobial Stewardship: Avoid misuse and overuse of antibiotics to reduce resistance.
  • Animal Welfare: Ensure therapy relieves suffering and improves quality of life.
  • Regulatory Compliance: Follow veterinary drug regulations, including prescription laws and withdrawal times.
  • Client Communication: Explain options, costs, risks, and prognosis clearly to the owner.


Decision-Making Framework
  • Confirm diagnosis.
  • Identify therapeutic goals (cure, control, palliation, prevention).
  • Evaluate available therapeutic options.
  • Select the most appropriate treatment (specific + supportive).
  • Consider safety, regulations, and client factors.
  • Implement treatment plan.
  • Monitor outcomes and adjust as needed.


Assessing a Patient's Prognosis

Introduction

A prognosis is the veterinarian’s prediction of the likely course and outcome of a disease or medical condition. It guides treatment decisions, informs client expectations, and helps in resource planning. Prognosis is based on the diagnosis, the animal’s overall health, and external factors such as management and environment.

Key Factors in Assessing Prognosis

1. Nature of the Disease

  • Acute vs. Chronic: Acute infections may resolve quickly with treatment, while chronic diseases may require long-term management.
  • Reversible vs. Irreversible: Conditions like mild pneumonia may resolve, while end-stage kidney failure is often irreversible.
  • Infectious vs. Non-infectious: Some infectious diseases are highly fatal (e.g., rabies), while others may be mild or self-limiting.

2. Stage and Severity

  • Early detection often improves outcome.
  • Advanced, severe, or systemic disease generally carries a poorer prognosis.

3. Species, Breed, and Age

  • Young animals may recover faster but are more vulnerable to severe disease.
  • Some breeds have genetic predispositions affecting outcomes.
  • Geriatric animals often have reduced healing capacity.

4. Response to Treatment

  • Rapid improvement after therapy suggests a good prognosis.
  • Poor or no response may indicate resistance, chronicity, or irreversible damage.

5. Concurrent Conditions

Co-morbidities (e.g., parasitism, malnutrition, metabolic disorders) complicate recovery.

6. Management and Environment

  • Adequate nutrition, housing, and care improve recovery chances.
  • Stressful or unhygienic conditions worsen prognosis.

7. Economic and Ethical Considerations

  • In production animals, prognosis is linked to economic value and productivity.
  • In pets, quality of life and owner willingness/ability to treat are major factors.
Types of Prognosis
  • Favorable (Good): High chance of full recovery.
  • Guarded: Outcome is uncertain; depends on treatment and external factors.
  • Poor/Unfavorable: Low chance of recovery even with treatment.
  • Grave/Hopeless: Recovery is not possible; euthanasia may be considered to prevent suffering.
Communicating Prognosis
  • Use clear, non-technical language with clients.
  • Be honest but compassionate.
  • Emphasize uncertainty when appropriate—avoid absolute predictions.
  • Provide options (treatment, palliative care, euthanasia).


Veterinary Examination of a Herd

Introduction

While clinical examination of an individual animal is essential, in herd medicine the veterinarian often deals with the health status of an entire group. Herd examination focuses on identifying disease patterns, assessing management practices, and preventing economic losses. It requires both individual animal assessment and population-level evaluation.

Objectives of Herd Examination

  • Detect health problems affecting groups of animals.
  • Identify risk factors in nutrition, housing, and management.
  • Monitor productivity and welfare indicators.
  • Provide preventive strategies (vaccination, deworming, biosecurity).
  • Support decision-making for treatment, culling, or management changes.

Components of Herd Examination

1. History Taking (Herd Anamnesis)

  • General Herd Information: size, age/production groups, breed, purpose (dairy, beef, poultry, etc.).
  • Management Practices: housing, feeding, milking, biosecurity, vaccination, deworming.
  • Production Records: milk yield, weight gain, fertility, mortality, morbidity rates.
  • Previous Diseases: outbreaks, treatments, culling patterns.

2. Environmental Assessment

  • Housing and ventilation.
  • Stocking density and space allowance.
  • Hygiene and sanitation.
  • Access to feed and water.
  • Pasture or feedlot conditions.

3. Observation of the Herd

  • From a distance: general behavior, activity, feeding, and social interactions.
  • Look for coughing, nasal discharge, lameness, diarrhea, abnormal posture.
  • Assess body condition scores (BCS) across groups.
  • Mortality or culling trends.

4. Clinical Examination of Representative Animals

  • Select a sample group (random + affected animals).
  • Perform general examination (vital signs, mucous membranes, BCS).
  • Specific system checks depending on herd complaint (e.g., udder exam in dairy cattle, respiratory system in feedlots).
  • Laboratory sampling: blood, feces, urine, milk, feed, water.

5. Production and Health Records Review

  • Fertility rates (conception, calving interval, abortion rates).
  • Milk yield, growth rates, feed conversion efficiency.
  • Mortality/morbidity statistics.
  • Drug and vaccine usage.

    • 6. Special Herd-Level Examinations

    • Parasitology: fecal egg counts.
    • Metabolic profiling: blood/urine for mineral or metabolic status.
    • Milk quality tests: somatic cell counts, mastitis screening.
    • Post-mortem examinations: valuable for sudden deaths or chronic issues.

    7. Interpretation and Herd Diagnosis

    • Differentiate between individual animal problems and herd-level issues.
    • Identify patterns: age group affected, seasonality, management links.
    • Classify problems: infectious, nutritional, environmental, or multifactorial.

    8. Outcome of Herd Examination

    • Herd Health Status Report – summary of findings.
    • Identification of Risk Factors – management, environment, nutrition.

    Recommendations

    • Therapeutic measures (if outbreak present).
    • Preventive strategies (vaccination, biosecurity, parasite control).
    • Management adjustments (housing, feeding, culling).
    • Monitoring Plan – follow-up visits, record review, regular sampling.