The importance of vitamins is now well recognized from requirement point of view on the basis of their chemical nature, physiological, functions, metabolism and symptoms of deficiency. Rickets, osteomalacia, night blindness, parakeratosis, infertility, haemorrhagic sweet clover disease, beriberi, polyneuritis, curled toe paralysis, scurvey and pellagra are some of the disease occurring as a result of different vitamin deficiencies.
Vitamins are therefore, accessory food factors which are not only required for productive purposes but are essential from disease prevention point of view. The requirements of vitamins depend upon the physiological status of Animals. The needs are likely to according to nutritional status, age, health and functions.