Vitamins for Rabbits - Requirements, and Deficiencies

Like human beings, rabbits require several types of vitamins but in small amounts. They can be divided into water-soluble comprised of vitamin B complex and C as well as fat-soluble ones which are made up of vitamin A, D, E and K.

Each of them has its function, and lack of any will cause illness or deficiency symptoms. On the other hand, excessive can also be toxic.

Their general functions include promoting their resistance to diseases and keeping their body healthy

Although Vitamin B complex and K are available in some commercial diets for rabbits, they can make their own through cecotrophy. They are produced during the fermentation of soluble fibers by bacteria.

On the other hand, vitamin A, D and E must be provided to your bunnies diet. However, they relatively require lower amounts of vitamin D and E and can be met by the various foods they eat. However, for vitamin A, you must ensure the diets has enough.

Vitamin A functions, toxicity, and deficiency

This is a fat-soluble vitamin that can be obtained from the grass as well as various fresh green foods especially the dark leafy ones.

This vitamin is stored in the liver of a rabbit and very essential in ensuring membrane integrity, reproduction, growth, development of various body tissues and it helps with vision[2]. It can also help fight infections and aids in immunological responses.

Vitamin A deficiency is associated with retarded growth, lack of coordination, blindness, and paralysis. For instance, it is vital in cartilage formation, and therefore, a deficiency will be indicated by dropping ears. If a doe lacks it, the offspring will suffer from hydrocephalus.

Finally, toxicity caused by excessive amounts and it is associated with problems such as weak and smaller litters, higher kit mortality, hydrocephalus (the kits will have fluids in their brain), and cases of resorption of fetal[1].

Expect toxicity if you supplement vitamin A to bunnies having high diets of alfalfa which has high amounts of beta-carotene, a precursor of this vitamin. Carotene, a precursor, is found in plants in which the rabbit’s body can turn into vitamin A and note that dark green leafy plants have more of it.

Recommended amounts vary from 6,000 IU/kg to 10,000 IU/kg with the National Research Council stating 16,000 IU/kg as the maximum safe levels.

Vitamin E role and deficiency symptoms

Some of its sources include green cereals such as green peas and beans,  forage with younger dark leafy parts having more than older leaves or stems. Hay may not contain much since the making process leads to some losses.

Some of the leading roles that vitamin E plays in the rabbit’s body include the following:

1. It works with selenium to prevent oxidation of cells (avoid the destruction of muscle tissues), and it helps in maintaining the immunity Deficiency of the vitamin E and selenium causes muscular dystrophy, fetal resorption, and infertility. Also, the meat of rabbits fed with higher amounts of vitamin E has better color, greater stability, longer shelf-life, and lesser dripping losses[2].
2. The above observation shows that is also involved in the stability of membrane structure and blood clotting.
3. The other role is in the regulating of the synthesis of xanthine dehydrogenase

On the other hand, deficiency can cause lactation problems, exudative diathesis, disorders in their liver, muscular dystrophy and heart muscle damages.[3] In kits, vitamin E deficiency effects include muscular dystrophy, paralysis of hind limbs and death[6].

Pet rabbits can have between 40 to 70 mg per kg of food given.

Vitamin B Complex

Vitamin B complex comprises of thiamin, riboflavin, niacin, biotin, pantothenic acid, pyridoxine, folic acid, B12 as well as choline. The rabbit’s hindgut’s bacteria can synthesize them, and they will be absorbed in the small intestines once bunnies eat their cecotrophs, where they are packaged.

Let us look at a few of the roles each of these vitamins have as well as how their deficiency can be signaled.

• Thiamin (B1) – Works as an enzyme cofactor that plays a vital role in fat and carbohydrate metabolism. Deficiency will cause muscle paralysis and loss of appetite.
• Riboflavin (B2) – Helps in the oxidation of glucose inside the body cells of rabbits. Lack of riboflavin can lead to a reduced conversion of feed as well as retarded growth.
• Niacin (B3) – Has functions like B2 and is one of the cofactor components involved in glucose oxidation inside cells. Fortunately, tryptophan, an amino acid can easily synthesis it. Deficiency leads to emaciation, diarrhea, and loss of appetite.[4]
• Pantothenic acid (B5) – It is vital in energy metabolism, induces an acceleration in the wound healing process[5] and its deficiency has not been noted in rabbits.
• Pyridoxine (B6) – This vitamin is involved in the metabolism of amino acids. It is often abundant as it is available in forage, grains and it can be synthesized inside the hindgut.
• Biotin (B7) – It plays a role in fatty acids metabolism, and its deficiency will cause hair loss and dermatitis.
• Folic and folate acid (B9) and cobalamin (B12) – These two are involved in the synthesis of nucleic acid. Anemia is one of the symptoms that indicates one lacks it. Folic acid plays a vital role in the interconversion of amino acids.
• Choline – Rabbits can synthesize Experiments that induce its deficiency leads to anemia, retarded growth, muscular dystrophy, and death.

Vitamin C – Ascorbic acid

It helps in biochemical reactions that encompass oxygen, and the liver synthesizes it. Furthermore, it is not required in the rabbit’s diet. However, the synthesis may be affected by severe conditions such as stress, weaning, hot weather, and some illness. In such instances, the production reduces, and a bunny might require additional sources.

Vitamin D

Vitamin D helps regulate the absorption of phosphorous and calcium by controlling calcium-binding protein in most animals. However, rabbits do not require the calcium-binding protein, and the amount of calcium absorbed will be relative to the one provided in the diet. However, it plays a role in calcium absorption among others whose deficiency has proved.

Bunnies are likely to have a vitamin D toxicity that deficiency. Levels around 2300- 3000 IU/kg can cause toxicity characterized by soft tissue calcification, loss of appetite and impaired movements. Therefore 1000 to 1500 IU/kg are the recommended levels.

It can be absorbed from the sun or gotten from various foods in case you suspect a deficiency. Deficiency has been associated with a weak immune system, heart problems, and dental disease[6].

Vitamin K

It helps in blood clotting and symptoms such as placenta hemorrhage and miscarriages as well as prolonged bleeding after a minor injury is observable. Vitamin K2 may help prevent atherosclerosis progression and coagulative tendency. This is achieved by total-cholesterol reduction[7].

Its deficiencies are not so common since rabbits can synthesize it in their hindgut, and during cecotrophy, it will be absorbed in the small intestines.

Further References

• Ringer, D. H. and G. D. Abrams. 1971. Laboratory diagnosis of vitamin E deficiency in rabbits fed a faulty commercial ration. Lab. Anim. Sci. 21(3):383-38
• Mateos, G.G., and de Blas, C. (1998) Minerals, Vitamins, and Additives. In. de Blas, C, and Wiseman, J. (ed) The Nutrition of the Rabbit. CABI Publishing, Oxon, UK, pp. 145-175.