Dietary Phosphorus Requirement of Channel Catfish (Ictalurus punctatus)

When channel catfish fingerlings were fed semipurified diets supplemented with monobasic sodium phosphate, their minimum requirement of dietary phosphorus for satisfactory growth and bone mineralization was approximately 0.45%. The addition of calcium (calcium carbonate) to a phosphorus-supplemented diet increased growth rate slightly but not significantly. Availability of phosphorus for channel catfish, as determined by net absorption from the digestive tract, was 90-94% for monosodium and monocalcium phosphate, 65% for dicalcium phosphate (feed-grade), 40% for fish meal, 50-54% for soybean meal, and 25-28% for cereal products.