Mineral deficiency

Minerals are required for the normal life processes, and all animals, including fish, need these inorganic elements. Fish may derive these minerals from the diet and also from ambient water. The minerals are responsible for skeletal formation, maintenance of colloidal systems, regulation of acid-base equilibrium and for biologically important compounds such as hormones and enzymes.

Mineral deficiencies can cause biochemical, structural and functional pathologies which depend on several factors, including the duration and degree of mineral deprivation.

Summary of Information on Mineral Requirements of Fish

Mineral element	Principal metabolic activities	Requirement symptoms	Requirement /kg dry diet
Calcium	Bone and cartilage formation; blood clotting; muscle contraction	not defined	5g
Phosphorus	Bone formation; high energy phosphate esters; other organo-phosphorus compounds	Lordosis, poor growth	7g
Magnesium	Enzyme co-factor extensively involved in the metabolism of fats, carbohydrates and proteins	Loss of appetite, poor growth, tetany	500 mg
Sodium	Primary monovalent cation of inter cellular fluid; involved in acid-base balance and osmoregulation	not defined	1-3g
Potassium	Primary monovalent cation of intra-cellular fluid; involved in nerve action and osmoregulation	not defined	1-3g
Sulphur	Integral part of sulphur amino acids and collagen; involved in detoxification of aromatic compounds	not defined	3-5g
Chlorine	Primary monovalent anion in cellular fluids; component of digestive juice (HCl); acid-base balance	not defined	1-5g
Iron	Essential constituent of haeme in haemoglobin, cytochromes, peroxidases, etc.	Microcytic, homochronic anaemia	50-100 mg
Copper	Component of haeme in haemocyanin (of cephalopods); co-factor in tyrosinase and ascorbic acid oxidase.	not defined	1-4g
Manganese	Co-factor for arginase and certain other metabolic enzymes; involved in bone formation and erythrocyte regeneration	not defined	20-50 mg
Cobalt	Metal component of Cynocobalamine (B12). Prevents anaemia; involved in C1 and C3 metabolism	not defined	5-10 mg
Zinc	Essential for insulin structure and function; co-factor of carbonic anhydrase	not defined	30-100 mg
Iodine	Constituent of thyroxin; regulates oxygen use	Thyroid hyperplasia (goiter)	100-300 mg
Molybdenum	Co-factor of xanthine, oxidase, hydrogenases and reductases	not defined	(trace)
Chromium	Involved in collagen formation and regulation of the rate of glucose metabolism	not defined	(trace)
Fluorine	Component of bone appetite	not defined	(trace)