Short Communication: Behavioral and Physiological Indicators of Sensitivity or Chronic Pain Following Tail Docking

Abstract

Docking the tails of dairy cattle causes mild to moderate behavior changes and physiological indicators of acute pain, but no studies have investigated the possibility that tail docking may lead to chronic pain. In human amputees, an incidence of increased limb surface temperature is associated with phantom limb pain, a central nervous system representation that survives peripheral loss. The objectives of this study were to assess indicators of sensitivity or chronic pain in heifers by using behavioral indicators and thermography. We tested 14 Holstein heifers, 7 docked and 7 intact, from a previous neonatal tail-docking experiment. All 14 animals were videotaped 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. A thermal image of the tail was taken using infrared imagery prior to and after temperature sensitivity testing. Docked heifers tended to have greater changes in surface temperatures following the test sequence than did nondocked heifers. In docked heifers, temperatures on the underside of the tail were higher than those at the tip of the tail, both prior to and following the test sequence. Docked heifers also showed substantially higher stomping activity following application of the cold pack. Shifting increased in intact heifers after application of the hot pack, but shifting of the docked heifers did not change. Greater changes were observed in the tail surface temperatures of the docked heifers following temperature manipulation, similar to human amputees who are experiencing phantom limb pain, indicating that similar mechanisms are present in the stump of the docked tail. The behaviors of docked heifers indicated changes in their sensitivity to heat and cold.

Tail docking in pigs: acute physiological and behavioural responses

“…It would be interesting to determine whether these CAUT piglets experience more distress later on when the nociceptors regenerate compared with piglets docked using the BT method. Neuromas were found to be present in the tail stump of docked pigs (Simonsen et al, 1991) and tail-docked heifers showed increased sensitivity to heat and cold (Eicher et al, 2006), suggesting that these animals may experience increased sensitivity to pain and chronic discomfort due to tail docking. However, the present study was designed to determine the acute physiological and behavioural effects of tail docking, not the long-term consequences.…”

“…The absence of scooting behaviour in combination with CON level cortisol concentrations in tail-docked pigs 90 min after tail docking suggests that these animals experienced transient stress due to tail docking, which was minimal 90 min after tail docking. However, these animals may experience chronic pain or stress due to increased sensitivity in the tail stump owing to neuroma formation (Simonsen et al, 1991;Eicher et al, 2006). Further studies are needed to determine whether tail docking of piglets results in chronic pain or stress due to this procedure.…”

Tail Docking in Pigs: A Review on its Short- And Long-Term Consequences and Effectiveness in Preventing Tail Biting

“…The existence of changes in the sensitivity of pig tail after docking has not been demonstrated so far. However, Eicher et al (2006) observed in heifers' docked tail an increased sensitivity to heat and cold. Di Giminiani et al (2011) recently proposed the use of an electronic Von Frey anesthesiometer directed at the mid-section of the tail to assess the mechanical pain sensitivity in the tails of growing pigs.…”

Pre-transport factors affecting the welfare of cattle during road transport for slaughter – a review

“…It is well documented that transportation is more likely to affect adversely the welfare of a calf than a mature animal (older than 17-19 months), because of the incomplete development of the calf's hypothalamic-pituitary axis (Eicher et al 2006) and because of the fact that calves are exposed to a multitude of novel and stressful events, including weaning, processing, handling etc. around the time they are transported (Grandin 2001).…”