Pig farm with respiratory disease and antibiotic use
A 600-head finishing pig unit reports increased coughing and a 5% mortality rate over 2 weeks. Post-mortem examination of two pigs shows pleuritis and lung consolidation. The farm currently uses in-feed chlortetracycline at a growth-promotion dose (no veterinary prescription) and has no written treatment protocol. The veterinarian suspects Actinobacillus pleuropneumoniae or Mycoplasma hyopneumoniae. The farmer wants to increase the antibiotic dose in feed and asks whether this is allowed without a prescription.
1. What is the correct diagnostic and treatment approach for this respiratory outbreak?
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Diagnostics:
- Submit lung and pleural samples for culture and sensitivity, and PCR for A. pleuropneumoniae and M. hyopneumoniae.
- Review vaccination status.
Treatment:
- Do not use growth-promotion doses; use a therapeutic dose under veterinary prescription based on sensitivity results.
- Choose an appropriate antibiotic (e.g., a macrolide or tetracycline if sensitive) with correct dose, duration, and withdrawal period.
- Improve ventilation, stocking density, and biosecurity.
Reasoning: empirical dose escalation without diagnosis risks treatment failure and antimicrobial resistance; culture and sensitivity should guide therapy.
2. What legal and professional issues arise from the current in-feed antibiotic use?
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Legal/professional issues:
- Growth-promotion antibiotic use without veterinary prescription is generally prohibited under EU and Ukrainian veterinary legislation; antibiotics are prescription-only medicines.
- All treatments must be recorded, with withdrawal periods observed before slaughter.
- The veterinarian has a duty to correct non-compliant practice and document advice.
- Antimicrobial stewardship: use of antibiotics for growth promotion is contrary to responsible-use principles.
Reasoning: the farmer's request to increase the dose without prescription cannot be endorsed; the veterinarian must refuse and implement a compliant protocol.
3. What public health and food safety measures should be implemented?
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Measures:
- Establish withdrawal periods for any treated pigs and ensure no pigs are sent to slaughter before expiry.
- Maintain treatment records and medicine logs.
- Monitor for residues if there is doubt.
- Implement biosecurity to prevent spread and reduce the need for antibiotics.
Reasoning: residue violations are a food safety risk, and the veterinarian is responsible for ensuring withdrawal compliance.