You only need a very small pinch in the water bottle. Vitamin D Vitamin D is another fat soluble vitamin. As with Vitamin A, both deficiency and excess can cause health problems. Feed for rabbits and guinea pigs should contain no more than 1,600 iu per kilogram food. 1,200 iu would be quite adequate.
Vitamin D is important for the utilisation of calcium.
Lack of this vitamin can contribute to calcium deficiency. As vitamin D can be synthesised by the body from the UV light of the sun, access to an outdoor run in the summer can help maintain adequate levels of this vitamin whereas animals kept in sheds without access to much natural daylight might be prone to deficiency if the level in the food was low. Vitamin E Vitamin E is important for cardiac health, fertility and maintenance of pregnancy in guinea pigs. Lack of it can lead to infertility, abortion, stillbirth and neonatal death. If your food contains less than 50mg vitamin E per kilogram food, particularly if you are breeding, you should supplement the diet with wheatgerm, wheatgerm oil or Bemax.