1. Vitamin D & Your Pooch
Dr. Preethi Sudarshanie Dassanayake (B.V. Sc. , M. Sc., MBA)
Veterinary Teaching Hospital, University of Peradeniya
Sri Lanka
2. Vitamin D
Is a fat-soluble vitamin.
A steroid vitamin.
An essential vitamin for dogs.
Is a family of compounds that are derived from cholesterol.
Commonly found in two major forms (Vitamin D2 & D3).
D2 – Known as Ergocalciferol (found in plants).
D3 – Called as Cholecalciferol (found in animal tissues).
D2 & D3 are inactive and in the category of Prohormones.
3. Vitamin D activation pathway
Humans obtain sufficient amount of vitamin D through exposure to direct sunlight.
Your pet cannot synthesize this vitamin through exposure to the sunlight.
You have to supply it with foods or adding supplements.
Vitamin D absorb in the small intestine but in inactive form.
cholecalciferol (D3) 25- hydroxycholecalciferol (In the liver)
25- hydroxycholecalciferol 1,25-dihydroxycholecalciferol (In the kidney)
1,25- dihydroxycholecalceferol is known as Calcitriol (active form of vitamin D)
Excess vitamin D deposit in adipose tissue.
4. Functions of Vitamin D
Promotes calcium absorption in the gut.
Maintains serum calcium and phosphate level.
Prevent from hypercalcemic tetany
Proper bone growth and bone remodeling.
Facilitating healthy bones and teeth.
Improves muscle strength.
Improves immune function.
Reduces inflammation (anti-inflammatory).
6. The Association of American
Feed Control Officials (AAFCO)
Recommendation - 500 IU of
Vitamin D Per Kilogram of Dog
Food
IU means International Units.
1 IU = 0.025mcg
500 IU = 12.5 mcg
7. Vitamin D deficiency
Bones become thin.
Bones become brittle.
Misshapen bones.
Rickets.
8. Vitamin D toxicity
Hypercalcemia.
Loss of appetite.
Weight loss.
Excessive thirst.
Frequent urination.
Drooling.
Vomiting.
Muscle weakness.
Soft tissue mineralization.
Lameness.
Disrupt normal skeletal development (pups).
