Troubleshooting SNAP® Test Results

 
IDEXX SNAP tests are very reliable. However, if you have problems with a SNAP test, read the information below for help, and then rerun the test. 
 
 

No Color or Poor Color Development

  • Test may not have been prespotted.
  • Pellet in tube may have been stuck at the top and discarded inadvertently.
  • Heater may not have been at the correct temperature, 45°C ±5°C. (Does not apply to ST products.)
  • Sample may not have been incubated for the full incubation time. (Does not apply to ST products.)
  • SNAP device may not have remained on the heater for the full color development time. (Does not apply to ST products.)
  • SNAP device may have been presnapped or not completely snapped.
 
Rerun the test.
   
 

High Background Color

  • Heater temperature may have been above 50°C. (Does not apply to ST products.)
  • Sample may have been spilled onto the results window when it was poured into the sample well.
  • SNAP device may have been activated (snapped) late.
  • SNAP device may not have been fully activated (fully snapped).
 
Rerun the test.
   
 

Poor Spot Quality or Streaking

  • Abnormal-looking milk may have been used, or the sample may have been too thick to flow.
  • SNAP device may have been activated too early or too late.
  • Air temperature may have been too hot or too cold; please refer to product insert for specific requirements.
  • Heater may not have been at the correct temperature, 45°C ±5°C. (Does not apply to ST products.)
  • Pellet in sample tube may have been hydrated; this is often caused by removing the tube from the foil pack too soon. Do not remove test materials from the foil pack until you are ready to run test.
  • SNAP device may not have been fully activated (snapped).
  • SNAP device may not have remained on the heater for the full color-development time. See product-specific protocol for appropriate color development time. (Does not apply to ST products.)
 
Rerun the test.
   
  

Discrepant Results—Visual vs. SNAPshot® DSR Reader

  • The test may not have been prespotted, or there may have been other quality problems with the SNAP test spots.
  • The background color may not have been clear. This is known as "high background" or "high blue" (see “High Background Color” section, above).
  • SNAP device may not have remained on the heater for the full color development time. See product-specific protocol for appropriate color development time. (Does not apply to ST products.)
 
Rerun the test.
   
  

False-Positive Results

  • Heater temperature may have been above 50°C. (Does not apply to ST products.)
  • Sample may have been overincubated. Refer to package insert for correct incubation time. (Does not apply to ST products.)
  • SNAP device may have been activated (snapped) too late.
  • SNAP device may have been read before the full color development time.
  • Sample may have been poor; sample must be well-agitated.
 
Rerun the test.
   
  

False-Negative Results

  • Heater temperature may have been below 40°C. (Does not apply to ST products.)
  • Sample may have been underincubated, or the incubation step may have been skipped completely. (Does not apply to ST products.)
  • Sample may have been poor; sample must be well-agitated.
 
Rerun the test.
Troubleshooting SNAP Test Results
 

For information or to order:

Call IDEXX Technical Services, 1-800-321-0207.