CELLS, TISSUE AND INFECTION
Culture and Sensitivity Testing
Laboratory testing that helps identify certain bacteria and determine which antimicrobial medications may be effective.
THE SHORT VERSION
Testing helps answer a clinical question.
A culture allows selected organisms to grow from an appropriately collected sample. Susceptibility testing then assesses which antimicrobial agents are more or less likely to work against the identified organism.
What is this test?
A culture allows selected organisms to grow from an appropriately collected sample. Susceptibility testing then assesses which antimicrobial agents are more or less likely to work against the identified organism.
What information can it provide?
- The sample source may include urine, a wound, an ear or another location chosen by the veterinarian.
- Sterile or carefully collected samples are important because contamination can complicate interpretation.
- Susceptibility results guide antibiotic selection together with tissue location, safety and the animal’s history.
- Some organisms require specialized culture conditions or additional testing.
When might your veterinarian recommend it?
- Investigate a persistent, recurrent or complicated suspected bacterial infection.
- Support antimicrobial stewardship rather than repeatedly guessing at an antibiotic.
- Clarify whether a urinary or wound sample contains a clinically meaningful organism.
What can owners do before the visit?
- Tell the clinic about current or recent antibiotics before sampling.
- In some cases, collecting a sample before starting antibiotics improves interpretability when the animal’s condition allows.
- Never stop a prescribed antibiotic without explicit veterinary direction.
What can this test not tell you by itself?
- Culture results may require time, and an unstable animal may need immediate treatment before a result is available.
- Contaminated samples can grow organisms that are not causing disease.
- A susceptible laboratory result must still be evaluated against drug safety, location and species.
Do not change medication, interpret an abnormal number as a diagnosis or delay urgent treatment without direction from your veterinary team.
Useful questions for your appointment
- Is this the right sample and collection method for the problem?
- Could recent antibiotics change the result?
- How will the veterinarian select the safest effective medication and plan follow-up?