Methods for Pain Assessment in Calves and Their Use for the Evaluation of Pain during Different Procedures-A Review

Abstract

The evaluation and assessment of the level of pain calves are experiencing is important, as the experience of pain (e.g., due to routine husbandry procedures) severely affects the welfare of calves. Studies about the recognition of pain in calves, and especially pain management during and after common procedures, such as castration, dehorning, and disbudding, have been published. This narrative review discusses and summarizes the existing literature about methods for pain assessment in calves. First, it deals with the definition of pain and the challenges associated with the recognition of pain in calves. Then it proceeds to outline the different options and methods for subjective and objective pain assessment in calves, as described in the literature. Research data show that there are several tools suitable for the assessment of pain in calves, at least for research purposes. Finally, it concludes that for research purposes, various variables for the assessment of pain in calves are used in combination. However, there is no variable which can be used solely for the exclusive assessment of pain in calves. Also, further research is needed to describe biomarkers or variables which are easily accessible in the field practice.

Keywords: calves; cortisol; ethogram; pain management; substance P; welfare.

Figure 1

Image of the “bovine pain face” as described by Gleerup et al. (2015) [6], in a calf diagnosed with polyarthritis. The facial expression undergoes different changes due to pain. Note the position of the ears, the tension of the facial muscles and muscles above the eyes, and the dilated nostrils. The picture was taken by the author at the Clinic for Ruminants with Amulatory and Herd Health Services, LMU Munich.