The optimal growth of large breed puppies
	Nutrition plays an important role

 Growth plates

The increase in the length of bones takes place in the growth plates. The bones do not grow randomly, but only in the cartilage growth plates that are situated at the ends of the bones. During the growth process the carti-lage is mineralised and transformed into bone. This process continues until the bone has reached its final length.

Disturbances in this process can occur and lead to skeletal disease resulting in lameness and bone deformities. The shoulder joints and the elbow joints are most frequently involved. The stifle (knee), hock (ankle) and hip joint can be affected as well.

 Skeletal problems

Research in large breed dogs in Sweden, the United States, Germany, Australia and The Netherlands, has shown that these diseases are the result of abnormal development of the joint cartilage. The disease in the dog is known as Osteochondrosis (OC) or Osteochondritis Dissecans (OCD). On the other hand, overloading of the joints due to excessive weight can also lead to problems, with the most obvious example being Hip Dysplasia (HD).

Osteochondrosis (OC) and Hip Dysplasia (HD) are diseases that develop during growth. They are hereditary by nature and can be influenced by the environment, such as trauma. HD is characterised by poor fitting of the hip joint, either because of conformation of the ball, or of the socket, or both. If a dog has no HD when it is skeletally mature, it will never develop HD. However, when a dog has HD but it was not diagnosed as a youngster, it might be diagnosed later on the basis of the subsequent arthrosis. The same applies for OCD.

It has been shown in several studies (excluding genetic influences) that relative excess weight in growing puppies due to over-feeding (i.e. the puppy is too heavy for the age relative to size) results in a significant increase in clinical HD. From an orthopaedic standpoint, a lean puppy is preferred to an obese puppy. Any excess weight causes deformation of the hip joint (in fact: it will increase the risk for HD). The overall size (height at shoulder) will not be affected when feeding to keep a puppy in a lean condition. The puppy does not grow slower in size, it grows slower in body weight which is preferable.

 The risk of too much calcium intake

Calcium is required for the development of healthy bone tissue. It has been proven from extensive research, that calcium intake is the greatest risk factor for the development of OCD. When the calcium intake is too high, the risk of the dog developing clinical problems is increased. Excessive calcium intake can occur when calcium supplements are added to a complete and balanced food, when the animal is fed complete food that is too high in calcium or when the owner adds too much calcium to a "home cooked" diet. Adding calcium to complete and balanced diets should be avoided under all circumstances as the amount of calcium in these diets has been carefully controlled.

 The danger of too much energy intake

The development of Hip Dysplasia (HD) is not related to the longitu-dinal growth of bones, but is mainly influenced by nutrition. Excessive food intake (calories) during growth results in a higher risk of developing HD. The mechanism for this is related to the rapid increase in bodyweight and the relatively immature skeleton to support this bodyweight.

At birth the skeleton is largely cartilaginous and is gradually transformed into bone. Cartilage, when compared to bone, is flexible and it can, and will, change shape when exposed to loading forces. When the immature skeleton, and thus the immature hip joint is ‘overloaded’ by a dog’s excessive bodyweight (compared to its age) it is at risk of adapting the the shape of its hip joints and will become dysplastic.

HD is however, a hereditary disease and when the genes are not in the breed line, excess body weight for a given age will not result in HD. On the other hand, when the breed line is at risk for HD, it has been shown that over-feeding the puppy can dramatically increase the frequency and severity of the condition.

The same is true for the relative risk of OCD and the group of conditions referred to as Elbow Dysplasia (ED). Too rapid growth in bodyweight in-creases the risk of these conditions. Balanced growth in conjunction with a controlled bodyweight growth rate is optimal for the best end result; i.e. a fit and healthy dog. Using correct feeding amounts will ensure that the dog reaches its correct adult size and reaches optimal body condition.

 The protein level has no influence

Research into the growth of Great Danes (Nap RC, The Netherlands,) has shown that the protein level of a diet has no significant influence on skeletal development. High protein intake does not result in increased risk for OCD or HD, and there is no effect on the development in the longitudi-nal growth of the bone.

 Special growth nutrition

Given the high frequency of skeletal problems in large breed dogs, the good news is that there is nutrition available that is specially formulated to meet the needs of rapidly growing large breed puppies. These products take into account the latest research that looks at calcium as the major risk factor in the nutrition of large breeds and also advocates reducing overall energy intake to bring about controlled growth. Eukanuba Puppy & Junior Large Breed has been specially formulated to have a lower energy content and an adjusted calcium to energy ratio to support healthy growth. It gives every large breed puppy optimal nutritional support!