New Bolton Center Kennett Square, PA
Emergencies & Appointments:
Ryan Hospital Philadelphia, PA

National Botulism Reference Laboratory

National Botulism laboratory, Penn VetThe National Botulism Reference Laboratory at New Bolton Center provides diagnostic services for both suspected individual cases of botulism, as well as possible outbreaks.

As one of the few laboratories of its kind in the United States, the laboratory provides testing for samples from multiple animal species including equine, bovine, avian and canine, as well as suspected feedstuffs and forages.

Leading experts in clinical botulism are available for consultation to discuss clinical signs of affected animals, as well as epidemiological factors in order to determine the likelihood of a single case of botulism, or to help identify an outbreak.

Contact Information

Botulism Laboratory Technician

Raymond W. Sweeney, VMD
Laboratory Director

Penn Vet - New Bolton Center
382 West Street Road
Kennett Square, PA 19348

Available Botulism Assays

Botulism Types A, B and C real-time PCR:

Our laboratory tests all diagnostic samples using a real-time PCR assay for the detection of Clostridium botulinum types A, B and C toxin genes in vegetative cells after a culture enrichment step.  Finding C. botulinum organisms or spores in a fecal or GI sample of a horse or cow, or in a feed sample,  is strongly supportive of a diagnosis of botulism in animals exhibiting compatible clinical signs… samples from normal animals are rarely positive.

The mouse bioassay to detect preformed toxin in serum, feed, or other samples is no longer available in our laboratory. Serum samples are rarely of value in horses and cattle unless the clinical signs have a peracute onset and progression of clinical signs.  Serum samples from clinically affected dogs and birds are more likely to be positive for toxin, since a higher concentration of toxin in these species is required to cause disease.  If you have serum or other samples that you would like to have tested for preformed botulinum toxin by the mouse bioassay, this test is available at the National Veterinary Services Laboratory (NVSL). Please contact them at 515-337-7565 or visit their website for submission instructions.

Turnaround Time

Sample processing, including culture enrichment followed by PCR testing, requires approximately five days. Samples arriving in the lab before Friday will have results available the following Tuesday or Wednesday. It is recommended to contact the laboratory (phone: 610-925-6383) before shipping samples to confirm testing schedule for time-sensitive samples.

Cost of Diagnostic Testing per Sample

  • PCR for organism/spores: $150 a sample
  • There is also an accession fee of $25 for each group of samples submitted.

An invoice is sent to the submitting veterinarian upon receipt of the samples.

Samples to Submit

The best samples to submit for botulism testing are generally stomach/rumen contents, GI contents, feces, spoiled forages, parts of dead animals found in suspect feed, and soil from underneath affected areas.

How Samples should be packed


Approximately 2 ounces of liquid or 20 grams of solid sample is ideal for testing.  Samples should be sent in whirl-pack bags or other suitable small leak proof container.  Put each intestinal sample (contents only, please don’t send whole intestines or intestines tied off on either end) in a separate Whirlpak bag and clearly label with ID with a waterproof marker such as a Sharpie.

Storage and Shipping of Diagnostic Samples

  • If Samples are fresh and are to be sent immediately:  
    Pack in Styrofoam box with ice packs and send Standard Overnight via UPS or FedEx. 
  • If Samples will not be sent immediately:  
    Please store in freezer until ready to send, and then follow the instructions above.  

What to Include with Samples

Please include along with the samples a completed Submission Form (PDF) with a detailed clinical history including the number of animals affected, number showing clinical signs, number dead, progression of clinical signs, treatment of the animals, the suspected source, results on any other tests ran on the animals, etc.   If the animal has been necropsied, please attach a copy of the necropsy report.

Where to Send Samples


  Where to Send Samples Laboratory Contact Information
Attention:  Botulism Laboratory
New Bolton Center
382 West Street Road   
47 Myrin Building
Kennett Square, PA 19348

Terry Webb
Botulism Laboratory Technician
Ph: 610-925-6245
Fax: 610-925-6807

NOTE: Do not send samples to arrive Saturday or Sunday as we are not available to receive samples on the weekend.

Contact Information
  Type Name
 Title  Contact Information
Laboratory Terry Webb
Botulism Laboratory Technician

Ph: 610-925-6245

Case Consultations
Robert H. Whitlock, DVM, PhD

Emeritus Professor of Medicine

Ph: 610-960-2843

Case Consultations Amy Johnson, DVM
Assistant Professor, Neurology

Ph: 610-925-6283