Make the most of vitamin supplementation

摘要

Vitamin supplementation of feeds is no longer a question of preventing deficiency symptoms. Much recent work shows that higher levels can allow today's birds to perform to their genetic potential. Unlike amino acids, which may be ranked in terms oftheir limiting performance, the vitamins should be considered collectively. Vitamins are organic compounds that are indispensable for metabolic activities without serving as building substances themselves. With few exceptions, vitamins are not synthesised in the body and must be supplemented in feeds. Vitamins must be present in sufficient quantities in the diet to ensure the animal efficiently utilises carbohydrates, proteins, fats, minerals and water for health, maintenance and production functions such as growth, development and reproduction. If one or more of the vitamins are either unavailable or present in inadequate amounts, metabolic processes are impaired, leading to disturbances of productivity, growth inhibition and disease. Some vitamins are supplemented at more-than-adequate levels for their specific functions such as enhancing immunocompetence and quality of meat or eggs. Finding a cost-effective window of vitamin supplementation levels without compromising optimum performance of the animal is a daunting task for feed formulators and/or nutritionists. Moreover, vitamin supplementation is a dynamic process and should be guided by the concept of optimum vitamin nutrition.