Measuring the torque required to cause vertebral dislocation in cattle tails

• Published in: New Zealand veterinary journal Vol. 68; no. 2; pp. 107 - 111
• Main Authors: Laven, RA, Jermy, MC
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 03-03-2020
• Subjects: abusive injury; Animal Welfare; Animals; Biomechanical Phenomena; Cadaver; Cattle; Cattle - injuries; control; Fractures, Bone; Tail - injuries; tail break; Torque; Vertebrae; Veterinary medicine; Wounds and injuries; tail break; torque; abusive injury; control; Cattle
• ISSN: 0048-0169; 1176-0710; 1176-0710
• DOI: 10.1080/00480169.2019.1685019

Aim: To estimate, ex vivo, the torque required to cause vertebral dislocation of cattle tails.
Methods: Five tails from dairy cows, severed at the junction between the sacrum and the first caudal vertebra, were sourced from a slaughterhouse. Within 2 hours of slaughter, the severed end of each tail was clamped in a vice and a steel collar was placed halfway along the tail. A torque wrench was attached to the steel collar, which was then rotated to produce an audible and palpable vertebral dislocation, and the torque at the time of the break was recorded.
Results: The maximum torque required to break a tail was 20 Nm, the minimum was 9.8 Nm, and the uncertainty was 4.9 Nm.
Conclusion: The torque required to break a cow's tail is unlikely to be applied accidentally if cattle are handled following recommended best practice. Thus if cattle on a farm can be shown to have broken tails due to manipulation by farm staff, cattle handling is not meeting the recommended best practice of the New Zealand Dairy Cattle Code of Welfare.