Evaluation of the background for determination of vitamin requirements in pigs

The effects of vitamins on important production and performance traits have been evaluated from the present knowledge of the functions of vitamins in the organism and the effects of deficient and excess supplies.It is concluded that there is a lack of current knowledge on almost all aspects of quantitative metabolism of vitamins. Stress is laid on our need to understand problems of availability and sensitive parameters indicating the vitamin status of the organism.A clear distinction between the scientific determination of requirements, and the allowances recommended by advisers is emphasized. A safety margin has to be added to estimates of requirements to cover farm conditions.