Large breeds of dogs are predisposed to these problems because they have the genetic potential for excessively rapid growth. In rapidly growing, large breed puppies, maximal growth, and therefore increased body weight, can cause stress on the immature developing skeleton. Large breed dogs have decreased bone density compared to smaller breed dogs at this stage (Dammrich, 1991). Additionally, fast bone growth results in structural defects of bones that are in turn unable to accommodate an increased body weight (Dammrich, 1991).