|Sorrells, A - PURDUE UNIVERSITY|
|Schutz, M - PURDUE UNIVERSITY|
Submitted to: International Society of Applied Ethology
Publication Type: Abstract Only
Publication Acceptance Date: August 4, 2001
Publication Date: N/A
Technical Abstract: Possibilities of improved hygiene, reduced labor, and greater milk quality has increased the popularity of tail docking dairy cattle in the U.S. Although recent research suggested little evidence of acute pain, chronic pain has not been thoroughly investigated. In human amputees, incidence of increased limb surface temperature is associated with phantom limb pain. Our objective was to assess sensitivity and possible chronic pain in dairy heifers by behavioral and temperature measurements. Holstein heifers, 7 docked and 7 non-docked, from a previous neonatal docking experiment were tested. All fourteen animals were video taped during a test sequence of alternating cold (-9 degrees C), hot (54 degrees C), and neutral packs applied to the underside of the tail. Packs were placed approximately 30.5 cm from the tail head on all animals. Then a pressure test was performed using a pin-pressure needle. A thermal image of the tail was taken using eMerge infrared imager prior to and after testing. Data were analyzed as a CRB design using PROC MIXED in SAS. Docked heifers tended to have higher surface temperatures following the test sequence than did non-docked heifers (F=3.49, DF=1, 8, p=0.09). For docked heifers, the underside of the tail showed significantly higher temperatures than did the tip of the tail prior to(F=8.87, DF=1,10, p=0.01) and following the test sequence(F=30, DF=1,10 p=0.0003). Docked heifers also showed substantially higher stomping activity following the cold pack (F=7.27, DF=1, 8, p=0.03). However, docking did not effect pressure sensitivity or weight shift, tail swings, and tail curve. Evidence of higher surface temperatures in docked heifers suggests chronic pain and the possibility of phantom limb pain.