In contrast to extensive and semi-intensive culture systems where fish obtain all or part of their nutrient needs from naturally available food organisms, fish maintained under intensive culture systems rely totally on the provision of a nutritionally complete diet throughout their culture cycle. For many farmed fish species the development of complete artificial rations (for use within intensive culture conditions) has proceeded despite the lack of information being available on basic nutrient requirements. It is perhaps not surprising therefore that nutritional pathologies resulting from specific nutrient deficiencies or imbalances often occur. This paper will endeavour to highlight the major nutritional pathologies which have been reported in fish fed artificial diets with no access to natural food organisms.
