Chronic Wasting Disease (IHC)

Detection of abnormal prion protein, the suspected causative agent of chronic wasting disease, in either antemortem samples (biopsies of retropharyngeal lymph node, tonsil, or rectal wall), or postmortem samples (retropharyngeal lymph node or obex) by immunohistochemical staining.

Antemortem: biopsy of the retropharyngeal lymph node, tonsils, or rectal wall in 10% neutral buffered formalin (NBF). 

Postmortem: one of the following: retropharyngeal lymph node, obex, or entire brain in 10% neutral buffered formalin (NBF). Entire head also accepted.

Fresh obex and retropharyngeal lymph node are also accepted.

Fixed samples: sealed, leak-proof, wide mouth plastic container. Samples submitted in glass containers are not acceptable and will incur an additional processing charge. 

Entire head: chill to refrigeration temperatures before packaging. Wrap in a plastic bag, preferably large zipper lock bags or leak-proof bags securely sealed with packing tape. Place inside second leak-proof plastic bag, with sufficient absorbent material and freezer packs. Place inside third bag and tape shut. Place paperwork in a separate, sealed plastic bag.

Label all samples. Ship fixed tissue at ambient temperature. Ship fresh tissue overnight on cold packs. Place paperwork and the head in a shipping container. The outer container should be insulated and crush-proof. Large plastic picnic coolers are ideal and do not need to be placed inside a cardboard box for shipping. Cardboard boxes without rigid coolers are not appropriate as condensation causes them to fall apart in shipping

Turnaround times vary due to the testing surge associated with the TPWD mandatory CWD testing requirements. 

If entire heads are submitted, TVMDL will collect obex and retropharyngeal lymph nodes for an additional charge of $23.00/per animal; a $23.00/animal head disposal fee will also apply. 

Include the TWIMS submission form which can be accessed through your Texas Parks and Wildlife Department TWIMS account.This is a test for a disease agent regulated by the Texas Animal Health Commission (TAHC) and/or the United States Department of Agriculture’s Animal and Plant Health Inspection Service (USDA APHIS). Samples, documentation, and testing may be subject to additional requirements or restrictions as determined by TAHC or USDA APHIS.