Abstract #T75

# T75
Effect of herbal liniment on equine back pain over time: a preliminary study.
Shannon M. Heibeck*1, Kelly W. Walter1, Jay A. Altman2, Brady J. Karren2, Miriam B. Altman3, Kevin K. Haussler4, 1Agricultural Science Department, Truman State University, Kirksville, MO, 2Arenus, Fort Collins, CO, 3Organic Exchange Ltd, Fort Collins, CO, 4Clinical Sciences Department, Colorado State University, Fort Collins, CO.

Previous research established pressure algometry as a quantitative and repeatable method of assessing induced musculoskeletal back pain in horses; however there is no data evaluating large areas over time in response to pain-mitigating products. Stock-type horses (n = 18) were used in a completely randomized 44 d trial to investigate the efficacy of an herbal liniment solution to mitigate musculoskeletal back pain. Horses began the study after a 30 d rest and all were maintained in similar daily light work through use in university horsemanship classes and equestrian team practices for the entire 44 d. Horses were randomly assigned to treatment groups which consisted of a commercially available herbal liniment gel solution (SoreNoMore Ultra, Arenus) or a control gel solution (identical gel solution minus active ingredients) applied to the back daily following exercise at 0.02 cc per square cm. Evaluation of back pain was standardized by dividing the back into 4 equal quadrants lengthwise beginning at the highest point of the withers and ending at the sacroiliac joint. Quadrants extended 17.78 cm ventrally from the spine. The third quadrant (on left and right side) was selected as the area of interest and was clipped to maintain consistency over time. Nine data points in this quadrant were selected (top-left, mid-left, bottom-left, top-mid, center, bottom-mid, top-right, mid-right, bottom-right) for weekly evaluation using a force gage pressure meter (by a single nonblinded examiner). A negative pain response was classified as no reaction to the application of 5.9 kg pressure. Data was inverted to create a 0 to 13 pain score based on the amount of pressure applied. Data were analyzed using the PROC MIXED procedure of SAS with main effects tested being treatment, time, and treatment × time interaction. Treated horses decreased mean pain score from beginning to end of trial (2.87 decrease; P < 0.001) compared with control horses (0.72 decrease; P ≤ 0.18). In summary, standardized evaluation procedure using pressure algometry suggests the herbal liniment gel solution was able to mitigate pain response when applied daily over a 44-d period.

Key Words: horse, back pain, liniment