1. Role in the body
- Vitamin D plays an essential role in the regulation of calcium and
phosphorus metabolism by increasing intestinal absorption of both
minerals, optimizing calcium incorporation into bone and reducing the l
loss of calcium and phosphorus in the urine.
- Ultraviolet rays (sunlight) convert 7-dehydrocholesterol in the skin to
- Many animals today are confined indoors and no sunlight is available.
Glass windows will also prevent UV rays, therefore, Vitamin D3
supplements must be included in the feed.
- Vitamin D deficiency before maturity, cause rickets (Not very common in dogs and cats) under-mineralization of bone, soft and fragile bone.
- Signs include; bone deformities (bowed legs), retarded growth, teeth abnormality, and general muscle weakness, joint and muscle pains, bone fractures.
- Vitamin D deficiency in old ages, cause Osteoporosis (Not very common in dogs and cats), calcium withdrawal from bone.
- Signs include; Weak, spongy or fenestrated and brittle bone that can be easily broken, joint and muscle pains.
- Hypervitaminotic or Vitamin D toxicity; Results in Hypercalcemia which can lead to calcification of various soft tissues, particularly the kidneys, lungs, arterial walls, myocardium and the intestinal tract.
- Skeletal abnormalities and eventually renal failure, cardiac upset, muscle tremors and seizures, effects are most pronounced in puppies and kittens .