Vitamins are organic compounds required as nutrients by the body. They are essential for many body processes; they protect the body from environmental toxins and break down the carbohydrates, fats and proteins so that the body can use them. Most vitamins cannot be synthesized by the organism and they need to be supplied in the diet.
Dogs need vitamins and minerals for a good digestion, for reproduction, muscle and bone growth and for a healthy skin and coat.
Vitamins are generally classified in two categories: fat-soluble and water-soluble.
- The fat-soluble vitamins (A, D, E and K) are stored in the liver before they are absorbed by the body (or excreted if the amounts are too large). Because they are stored in the liver, a deficiency of fat-soluble vitamins is more difficult to notice than one of water-soluble vitamins.
- The water-soluble vitamins (B1, B2, B3, B5, B6, B8, B8, B12 and C) are stored in very small amounts and this is why they need to be supplied on a daily basis.
Vitamin A (Retinol)
Vitamin A is very important for vision, good quality of skin and coat, healthy appetite. Vitamin A is usually converted from beta-carotene. It can be natural or synthetic. In commercial dog foods you can find it in its natural form under descriptions like: “from an algal source” or “natural beta-carotene”. The synthetic one is called simply “beta-carotene”. Signs of deficiency: Decreased vision, skin lesions, poor quality of skin and hair, retarded growth.
Vitamin D (Calciferol)
Vitamin D helps the body to absorb calcium and maintains a normal blood level of calcium and phosphorus. It is usually produced by the body under sufficient exposure to UV radiation. The necessary amount of vitamin D can be produced with 15 minutes of sunshine 3 times a week. Signs of deficiency: Bone malformations (rickets) like bowing of legs, thickening of the joints, incidence of fractures and poor eruption of permanent teeth.
Vitamin E (Tocopherol)
Has an important role in reproduction and acts as a natural antioxidant. It is also essential for the formation of red blood cells and it helps the body utilize vitamin K. Be careful with the vitamin E supplements which also contain a large amount of vitamin A as they can lead to vitamin A toxicity, especially if your dog’s diet is based on other sources of vitamin A. Signs of deficiency: Decreased reproductive performance, brown bowel syndrome, retinal degeneration, weak immune system.
Vitamin K (Naphthoquinone)
Vitamin K is essential for blood clotting. It can be produced by the bacteria present in the intestine. Signs of deficiency: increased clotting time and a tendency to bruise and bleed.
Vitamin B1 (Thiamine)
Vitamin B1 helps the body to convert carbohydrates into energy and proves to be essential for a proper functioning of the heart, muscles and nervous system. Signs of deficiency: loss of appetite, loss of reflexes, loss of nerve control, weakness, nerve damage. Severe deficiency can cause brain damage.
Vitamin B2 (Riboflavin)
This vitamin is important for growth, red blood production, breakdown of proteins, fats and carbohydrates and for the maintenance of a healthy skin and coat. Signs of deficiency: dry skin, weakness, anemia, poor growth, eye abnormalities, heart failure and decreased reproductive performance.
Vitamin B3 (Niacin)
Vitamin B3 is important for converting food into energy. It assists the functioning of the digestive system, the skin and the nerves. Signs of deficiency: loss of appetite, bad breath, increased salivation, inflamed gums, hemorrhagic diarrhea, emaciation.
Vitamin B5 (Pantothenic Acid)
It helps the metabolism with multiple enzyme reactions and the synthesis of hormones. The body doesn’t usually react if this vitamin is missing.
Vitamin B6 (Pyridoxine)
This vitamin is important for the skin and nerves; it helps the synthesis of antibodies by the immune system and acts in the formation of red blood cells. Signs of deficiency: anemia, poor growth, seizures and skin lesions.
Vitamin B8 (Biotin)
It has an important role for the protein and fatty acids processes. Its deficiency has no side effects.
Vitamin B9 (Folic Acid)
Works together with vitamin B12 and vitamin C to ensure a proper functioning of the digestive system and to synthesize and utilize proteins. This vitamin is also essential for the tissue growth, for the production of red blood cells and for the synthesis of DNA. Signs of deficiency: Anemia and hypoplasia of bone marrow.
Vitamin B12 (Cobalamin, Cyanocobalamin)
It helps the formation of blood cells and the proper functioning of the nervous system. Signs of deficiency: macrocytic anemia
Vitamin C (Ascorbic Acid)
It’s essential for many metabolic processes and for the proper functioning of the immune system. It is important that vitamin C is supplied in the diet particularly for dogs which suffer from chronic joint and musculoskeletal disorders. Vitamin C is synthesized in the liver and this is why pet companies and vets claim that supplementation in the diet is not necessary. This is not true. Signs of deficiency: decreased immune function, slowed wound healing.
Natural Sources of Vitamins
Here are the main natural sources of vitamins described by relevant photos.
Vitamins B3, B5 and B8 can usually be found in liver, lean meat, poultry, fish, eggs, nuts, yeast, legumes, asparagus, seeds, green leafy vegetables.
Hope you find this post useful!
Photos by courtesy of ADAM