Submitted to: Veterinary Record
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/29/2003
Publication Date: 5/22/2004
Citation: Bender, S., Alverson, J., Herrmann, L.M., O'Rourke, K.I. 2004. Histamine as an aid to biopsy of third eyelid lymphoid tissue in sheep. Veterinary Record. 154: 662-663. Interpretive Summary: A novel technique was developed to facilitate the collection of third eyelid tissue samples in sheep for use in diagnosis of scrapie, a transmissible spongiform encephalopathy. Histamine eyedrops were used prior to tissue biopsy to enhance the tissue, thereby making the biopsy procedure easier, and the sample collected of sufficient quality for an accurate diagnosis of scrapie. The use of histamine eyedrops will increase the accuracy of preclinical scrapie diagnosis in third eyelid tissue and will be of use to field veterinarians, animal health regulatory agencies, and the sheep industry.
Technical Abstract: Diagnosis of ovine scrapie, a transmissible spongiform encephalopathy, by third eyelid lymphoid tissue biopsy and PrPSc assay has been described. One of the biggest drawbacks to implementing routine field use of the third eyelid test has been obtaining adequate numbers of lymphoid follicles in each tissue biopsy for disease diagnosis. We describe a technique for enhancing third eyelid lymphoid tissue using histamine eyedrops that improved biopsy collection of third eyelid tissue with increased numbers of lymphoid follicles and did not interfere with PrPSc detection by immunohistochemistry assay.