Vitamins are organic substances characterized by the following properties: they are essential for the proper functioning of the body, they are active in low doses, they have a specific action, no vitamin is more important than another. The animal being unable to synthesize them all, they must therefore be present in the ration.
It is essential for the synthesis of retinal purple that is involved in vision and is necessary for the growth and protection of epithelial tissues and mucous membranes. Molecule involved in division and cell differentiation, vitamin A deficiency mainly affects growing animals if the diet does not contain supplementation. The clinical signs: They include reduced appetite and growth in cattle, changes in gait and lack of balance, seizures, diarrhea, cough, fever, and heat intolerance. The hairs become dull with the presence of pityriasis. In addition to these symptoms, important ocular signs appear: amaurosis, poor adaptation to darkness, papilloedema, retinal degeneration, changes in the cornea, conjunctivitis and aqueous humor, exophthalmos. A clinical case that we have described: Hypovitaminosis A in a breeding of bulls for fattening. 2004. P. LEBRETON, C. GARNIER, A. MEYUS, F. SCHELCHER, 2004, GTV Bull – Special Issue – Neuropathology of Ruminants.105-107
It is the vitamin of reproduction by its role antioxidant. It acts as a protector of cell membranes. Being a vitamin that plays a big role in cell growth, it is essential for reproduction but it also has anti-inflammatory properties. In case of proven deficiency, neurological, cardiovascular and reproductive disorders can be noted.
Unlike other B vitamins, Vit. B12 can not be synthesized by plants. It is produced exclusively by bacterial synthesis. Cobalt is an integral part of the Vit. B12. Unlike other water-soluble vitamins, Vit. B12 can be stored in tissues for a long enough period.
The functions of vitamin B12:
- Degraded homocysteine
- Provides genetic heritage to the cell (anemia, stillbirth, reproduction)
- Participates in the metabolism of fatty acids (steatosis, calves that do not suck, under production)
- Action on myelin (nervous disorders)
- Needed to convert C3 to succinate (appetite and energy)
- Cobalt via B12 is necessary for the biotransformation of antiparasitic molecules (benzimidazoles)
Signs of carence:
- Loss of appetite, stopping or slowing of growth
- A large rumen that no longer works
- Hair shaggy, pique, slimming, “big head”
- Anemia, deficiency induces an abnormal accumulation of iron in the liver that causes a noticeable decrease in hepatic copper, endothelial dysfunction, neurological disorders (necrosis of the cortex)
- Cobalt deficiency is similar to parasitic infestation!
- The liver is vulnerable because it can be parasitized, but also suffers from deficiency
- Under production
Vitamin D promotes the intestinal absorption of calcium and bone fixation of calcium and phosphorus. The symptoms of deficiency are rickets in young people and weakening of bones in adults. Hypervitaminosis D can cause hypercalcemia and soft tissue mineralization: heart, kidneys, lungs, vessels.
Biotin (or vitamin B8 or H):
Biotin is involved in cell growth, the production of fatty acids and the metabolism of fats and amino acids. Thus, it is essential in the formation of skin, hair and horny envelopes such as ruminant hooves or horse hooves. Inadequate production of biotin may occur in high producing cows, resulting in weakening of hoof horn and possible lesions. Studies show that the higher the concentration of concentrates in the cow ration, the less rumen microorganisms produce biotin (lower ruminal pH). It is therefore important to quantify the contribution of biotin because the rumen is likely to no longer be sufficient to meet the needs of the animal. When biotin requirements are not covered, we can notice a lower quality of hoofs and an increase in the problems of lameness, for example: laminitis, caused by the presence of toxins produced during ruminal acidosis (rich ration in concentrates). Biotin also has a direct role in milk production (role in energy and protein metabolism).