Fracture toughness of bovine claw horn from cattle with and without vertical fissures

The study was undertaken to determine whether the claw horn from cows suffering from vertical fissures (sandcracks) is weaker with regard to fracture formation than claw horn from cows without vertical fissures. Fracture toughness was determined using a composite testing procedure previously developed for use in equine hoof horn. Twenty cows with vertical fissures of the lateral front claw were compared with 20 case controls. Due to the calibration technique needed as part of the testing method results were obtained for only five animals in each group; cows with and without vertical fissures had median J-integrals of 8182 J/m2 and 8483 J/m2, respectively, but the difference was not statistically significant. Although the numbers are small it is suggested that since no difference existed in the fracture toughness of the claw horn from the two groups of cattle, vertical fissure formation is not directly dependent on the biomechanical property of the horn itself.