Function
- Are important to help release energy from food and energy stores
- Act as hormones to regulate metabolism
- Act as antioxidants to prevent cellular damage
Types
- Bunnies cannot make their own vitamins
- The structure of each vitamin is different, however, all are organic molecules found in trace amounts in bacteria or plants. They can be divided into two general groups.
- Water soluble vitamins (B-complex, C)
- Fat soluble vitamins (A, D, E, K)
Source
- The water soluble vitamins and vitamin K are synthesized by the cecal bacteria and obtained by coprophagy.
- Carotenes (plant pigments) are converted to Vitamin A in animal tissues.
- Pre-vitamin D is found in sun-dried alfalfa hay and can be synthesized by the skin after exposure to UV light.
- Vitamin E is found in vegetable oils and cereal grains.
Needs
- Rabbits do have an absolute requirement for all the vitamins except C.
- However, the vitamin K and the B-vitamins are provided by the cecal bacteria and therefore may not need further supplementation until the cecum is disturbed or the cecal pellets are not consumed.
- Rabbits receiving pellets as part of the diet should be receiving sufficient amounts of vitamins D, A, and E. For rabbits receiving no pellets, it is possible that D and E would become deficient after a long time (many years). Carrots, of course, are rich in vitamin A.
Dangers
- Extreme excesses of Vitamin C can cause kidney damage.
- Excess vitamin D can cause calcium deposits in tissues (joint, kidneys, etc.).
- Excess vitamin A causes neurological and skin damage.
Feeding Considerations
Mature house rabbits and Angoras
Normally should not need any vitamin supplements.
Older Rabbits
If they have difficulty re-ingesting cecal pellets, then B-vitamin supplements maybe appropriate.
Sick rabbits
May have the same B-vitamin requirement as older rabbits especially if the GI tract is disturbed or cecal pellets are not being eaten. Many people have reported appetite stimulation after injection with B-complex vitamins.
Growing rabbits
Liver stores and pellet sources of vitamins should be sufficient to support growth.