The minerals

Minerals are essential inorganic elements that have a significant impact on growth development and health of fish. Among vertebrates, fish are unique in their ability to absorb minerals from their diets but also from water across gills and skin. Although significant progress has been made in the past 2 decades on requirements of certain minerals (phosphorus, zinc, copper, and selenium), a major gap exists in the uptake, function, biological availability, and excretion of most minerals. Several deficiency signs including cataracts, skeletal deformities, and hatchability of eggs have been linked to trace element deficiencies. In recent years, major shifts from the use of fishmeal to plant ingredients have resulted in a focus on mineral bioavailability; however, interactions between minerals and their uptake from water justify a much broader approach in this area. This chapter provides a brief overview of the known functions, deficiencies, requirements, and bioavailability of minerals and identifies certain issues yet to be resolved.