Abstract. This study evaluated claw development in 199 calves of different genetic background during the first 70 days of life. Dual Energy X-Ray Absorptiometry (DXA) was found to be a useful tool for this purpose. By the means of DXA, in humans as in animals, body constitution and composition can be examined in vivo. Thus, the whole body or body regions can be analyzed for the content of fat tissue, lean tissue, bone mineral content and bone mineral density. Large differences in claw parameters were observed, depending on the position of the claws, sex and breed, including interaction effects between gender and breeds.

In all four pairs of claws, the medial claws had significantly higher contents of bone mineral than the lateral claws. All fore claws had a higher density than hind claws. Male calves showed significantly higher values than females in all measured parameters.

Comparing breeds and crossbreds, pure German Holsteins had the lowest values in all parameters with exception of the R-value. Within breeds/crossbreds and gender various interactions could be found. Calves of first lactation cows had lower values than calves of elder cows. Calves with a small birth weight and calves originating of a multiple birth had significantly lower values of the scanned parameters than calves with higher birth weight or monoparous calves.