Attenuation of Acute Plasma Cortisol Response in Calves Following Intravenous Sodium Salicylate Administration Prior to Castration

Abstract

Based on steer slaughter data from the National Agricultural Statistic Service (NASS) [1], more than 16 million bovine castrations are performed in the United States annually. The short term pain and distress inflicted by castration remain a major animal welfare concern for the beef cattle industry. However, the long term benefits of castration in the form of decreased aggression, improved carcass traits, and exclusion of genetically inferior animals make this a widespread animal husbandry practice. Research to investigate practical, effective methods for minimizing the pain and distress associated with castration is crucial to enhance the wellbeing of animals in production systems. Cortisol is widely used to measure stress since its response magnitude, duration and/or integrated response is reported to correspond with the predicted noxiousness of different procedures [2,3]. It has been shown that ketoprofen reduced plasma cortisol response to Burdizzo castration more effectively than local anesthetic or an epidural [2]. Intravenous ketoprofen, alone or in combination with local anesthesia, before surgery-cut castration was found to decrease the post-castration integrated cortisol response [3]Although not a specific indicator of pain, these studies support the use of plasma cortisol as a pharmacodynamic indicator of stress associated with castration. However, plasma analgesic drug concentrations and cortisol levels have never been concurrently evaluated in cattle post-castration.