The minerals calcium and phosphorous as well as vitamin D are essential for the formation and maintenance of strong bones. Deficiency in any of the above, or mineral imbalances, can result in the faulty formation of bones in dogs, referred to as osteodystrophy.
Calcium, and to a lesser extent phosphorous, can be obtained from the food in sufficient amounts, but certain problems with the absorption of these minerals may result in a shortfall. Vitamin D plays an important role in the absorption of these minerals, as do several other factors including their sources. The body can synthesize vitamin D when it is exposed to sunlight. It can be obtained from food stuffs also. But if there is a vitamin D deficiency due to any reason, it can decrease the absorption of phosphorous and calcium. Since these minerals and vitamin D have several functions in the body, their deficiency may cause metabolic problems in the dog besides skeletal abnormalities.
Too much of a good thing can be a bad thing also. Excess calcium, as well as higher than normal amounts of phosphorous, can aggravate the risk of dogs developing certain diseases that they are naturally prone to. For example, many giant breeds are genetically predisposed to hypertrophic osteodystrophy and osteochondrosis. Excess calcium supplementation may lead to their developing those diseases.
Rickets In Dogs
Rickets is considered a deficiency disease affecting young dogs, generally caused due to inadequate amounts of vitamin D and phosphorous in the food. Deficiency of calcium can also cause this disease characterized by soft bones that result in structural deformities.
The typical symptoms of rickets in dogs are pain in the bones and inflammation of the joints accompanied by bowed legs and a stiff gait. The puppy may have difficulty getting up, and may start limping. It may develop fractures too. Puppies with rickets have great reluctance for any physical activity including playing. When the bones are touched, they may react in pain. A type of fracture in which the bone bends and folds over itself, instead of breaking apart, is typical. These folding fractures are most commonly found in the long bones. The vertebrae may also be affected. Deformities in the legs due to non-uniform growth of the limbs are common. These abnormalities may be detected in the x-rays.
Rickets can be easily treated when fractures and permanent deformities have not occurred. In mild cases, modifying the diet may be sufficient to produce the desired effect. Vitamin D deficiency may be amended by exposing the dog to ultraviolet rays or sunlight.
Excess calcium levels are known to cause symptoms similar to rickets in dogs. This is more often found in dogs that are fed exclusively on meat. The reason for this type of osteodystrophies is the calcium-phosphorous imbalance in the diet.
Foods prepared for dogs at home may not provide all the essential minerals in the right proportion. On the other hand, commercially available dog foods are usually well-balanced, supplying calcium and phosphorous in the required ratio. Another good option may be proprietary foods prepared by a qualified veterinary nutritionist.