Structural characteristics of the bovine claw: horn growth and wear, horn hardness and claw conformation.

Claw quality is the product of horn characteristics, claw shape and anatomy and physiology of the inner structure. This paper aims to review some of the different approaches that have been employed to evaluate claw quality. The various factors that may influence horn growth and wear are reviewed, including physiological, seasonal, nutritional, environmental, management and anatomical aspects. Horn hardness is similarly described. Claw conformation is discussed, commencing with a brief outline of the various methods used to determine claw shape and size, followed by an account of some of the factors that influence claw conformation. The clinical importance of claw conformation in cattle is considered with particular reference to lameness, longevity and production traits. Finally, the prospect of improving claw quality by selection of bulls based on claw measurements is reviewed.