Mineral Requirements of Fish

Minerals are a type of basic elements. Mineral elements are the inorganic elements that are required for the management and maintenance of important physiological processes in the organism. Some important minerals are  Calcium, Phosphorus, Sodium, Sulfur etc. Minerals act as biological catalysts for enzymes, hormones and protein in the body. About 23 types of inorganic minerals perform the necessary functions in the organism. Of these, 7 are the minerals that the body needs in sufficient amount and such minerals are referred to as macro-elements. On the other hand, 16 minerals are required in very small amounts in the body of the organism; such minerals are called micro-elements or Trace Minerals. For proper body growth, Mineral Requirements of Fish is very important.

Secondary elements play a major role in the nutrition and production of fish along with other minerals. Supplemental food and water serve as a source of fish minerals. Fish can absorb these elements as ions with the help of gills and skin. Rui fish(Labeo rohita) get essential minerals from plankton and pond bottom animals and decomposed organic matter. In the absence of such elements, the growth of fish is reduced or diseases are caused by pests, their high presence also hinders the growth rate of fish. Fish not only absorb such inorganic nutrients through food but also from the external aquatic environment. Inorganic elements are inextricably linked with the way fish live.

General Functions of Minerals

Minerals play a role in regulating physiological functions and the maintenance the body of the organism. It plays the following role:

  • It plays a role in the formation of the external skeleton;
  • It plays a role in transfer of nerve stimulation and muscle contraction;
  • It plays a role in the formation of structural elements of cell tissues;
  • Acts as key ingredient in bone and tooth formation;
  • It plays an important role in absorption, controlling stress, diffusion, etc.;
  • Acts as essential component of enzymes, hormones and vitamins;
  • Maintains acid-base balance;
  • Regulates blood formation, blood clotting barriers and the normal functioning of the thyroid gland;
  • Assists in performing water metabolism, controlling blood volume and transporting gaseous material;
  • Electron transfer;
  • Enzyme activation;
  • Homeostasis control;

Classification of Minerals

Not all minerals are needed in the same amount in a fish diet. Minerals are mainly divided into the following two groups based on the amount of organisms needed.

  • 1. Macro elements
  • 2. Micro elements

1. Macro Elements: The minerals that are needed in large quantities for the normal growth of fish are called the main minerals or macro elements. Generally, 100 mg or more of these minerals are required in every kg of fish diet.  There are 7 main minerals for fish such as Calcium, Magnesium, Sodium. Potassium, Phosphorus, Sulfur and Chlorine. 

2. Micro Elements: For normal growth of fish, some minerals are required in very small amounts in the body of fish i.e. less than 100 mg per kg of balanced diet of fish and this small amount meets the nutritional needs of fish, such minerals are called secondary minerals or micro lements. There are 16 such minerals which are required in very small amounts in the body of the organism such as iron, iodine, copper, zinc, manganese, cobalt, molybdenum, silicon etc.

The following table lists the important major and minor mineral elements:

Macro Elements

Micro Elelents

Calcium (Ca)Magnesium (Mg)Sodium (Na)Potassium (K)

Phosphorus (P)Chlorine (Cl)Sulfur (S)

Iron (Fe)Zinc(Zn)Manganese (Mn)Copper (Cu)Iodine (I)Cobalt(Co)Nickel (Ni)Fluorine (F)

Chromium(Cr)Molybdenum (Mo)Selenium(Se)Vanadium (V)Tin(Sn)Silicone(Si)Aluminum (Al)Arsenic(As)

Macro Elements

Calcium(Ca)

 Calcium is a chemical mineral and has atomic number of 20. Calcium is found in the skeletons and scales of bony fish. It plays a role in regulating various physiological processes such as metabolism, nerve and muscle contraction and osmosis. Calcium is absorbed directly through the gastrointestinal tract, gills, skin and fins, and oral epithelium with the effectiveness of vitamin D3 and lactose. In freshwater fish, most of the calcium is absorbed through the gills and skin, and in marine fish it is absorbed through drinking water. Calcium intake varies due to differences in species and water chemistry. The required calcium intake of eel and carp is 0.34 percent.

Sources of Calcium

  • Limestone
  • Shell of snails and oysters
  • Crushed bones
  • Crab crushed
  • Rocky phosphate (30-40%)
  • Shrimp meal
  • Fish meal
  • Meat meal
  • Kelp meal
  • Alfalfa meal
  • Poultry droppings
  • Dry skim milk

Biological Function of Calcium

Calcium is directly involved in the development and formation of bones. It also plays an important role in a variety of physiological functions. Below are some important roles of calcium:

  • It is an important component of bones, cartilage of fish and also components of shells of crustaceans such as shrimp/prawn.
  • It stimulates the nucleus accumbens and releases thromboplastin to clot the blood.
  • It acts as a catalyst for a variety of enzymes such as pancreatic lipase, acid phosphatase, cholinesterase, ATPases, and succinic dehydrogenase.
  • It stimulates muscle contraction by activating enzymes, transferring aerobic consciousness from one cell to another.
  • It jointly with phospholipids regulates the permeability of cell membranes.
  • It plays an important role in the absorption of vitamin B12 in the stomach and digestive tract.
  • Regulates muscle contraction and expansion.
  • It plays an important role in nerve stimulation and transfer.
  • It regulates various functions of cells.
  • It regulates acid-base balance.

Phosphorus

It is a nucleic acid and an important component of the cell membrane. Phosphorus is a nonmetallic chemical mineral with atomic number of 15. It directly participates in cellular reactions in all types of energy production. It contributes to the metabolism of sugars, lipids and amino acids. Phosphorus is also found in skeletons and scales of bony fish. It acts as a component of different types of metabolic reactions and different types of molecules such as ATPase. Dissolved phosphorus is absorbed directly through the skin, fins and gills. Water usually contains very little phosphorus. Therefore, supplementary food plays an important role in filling the phosphorus deficiency. Vegetable foods such as cereals and oilseeds contain 50-60% phosphorus which is present as calcium or magnesium salts of phytic acid.

Sources of Phosphorus

  • Limestone
  • Bone meal
  • Meat meal
  • Fish meal
  • Poultry droppings
  • Rice husk,
  • Wheat husk
  • Yeast
  • Sunflower Seed meal
  • Cotton seed meal
  • Rape seed meal

Biological functions of Phosphorus

The main biological functions of phosphorus are mentioned below:

  • It is an important component of bones, cartilage and and shells of crustaceans .
  • It acts as an important component of phospholipids, nucleic acids, phosphoproteins such as casein, high-energy phosphate esters such as anion, hexose phosphate, creatine phosphate, and numerous enzymes.
  • It regulates acid-base balance.
  • It plays an important role in the metabolism of sugars, lipids and amino acids.
  • Moreover, it participates in the metabolic system of various body fluids.

Deficiency Signs of Phosphorus

  • The growth of fish is reduced;
  • The growth of fish is reduced;
  • Bone loss or deformity;
  • Disability of the cranial nerve;
  • It helps in increasing the amount of fat in the digestive tract;

Magnecium

It is a chemical mineral with atomic number of 12. It regulates the activity of important biological polyphosphate compounds such as ATP, DNA, and RNA and acts as a cofactor in a variety of enzymatic reactions. It plays an important role in respiratory adaptation of freshwater fish. It is absorbed directly through the digestive tract, gills, skin and fins. It is found in phytin (Ca or Mg salt of phytic acid) in vegetable foods along with calcium and phosphorus.

Sources of Magnecium

  • Meat and bone meal
  • Rice husk
  • Kelp meal
  • Sunflower Seed meal
  • Wheat husk
  • Tishi seed meal
  • Shrimp meal
  • Cotton seed meal
  • Crab crushed
  • Grass chicken droppings

Biological functions of Magnecium

The main biological functions of magnesium are mentioned below:

  • It is an important component of bones, cartilage and crustaceans shells.
  • It contains various major enzyme systems such as kinases, mutases, muscle ATPases and enzymes such as cholinesterase, alkyne phosphatase.
  • It acts as a catalyst for inlase, isocytic dehydrogenase, arginine, deoxyribo nuclease and glutaminease.
  • It plays a role in regulating intracellular acid-base balance.
  • It plays an important role in the metabolism of sugars, carbs and fats.t

Deficiency Signs of Magnecium

  • The tendency of fish to eat decreases;
  • Physical growth decreases;
  • The vertebrae, muscle fibers, epithelial tissues of the pyloric system and gill filaments are eroded.
  • Blindness
  • Renal calcinosis

Sodium

It is a chemical mineral element with atomic number of 11. Sodium is the monovalent ion of extracellular fluid. It is found in the bloodstream and 93% of the total ions are sodium ions. It regulates osmotic pressure and pH levels. This material is absorbed directly through the alimentary canal, gills, skin and fins.

Sources of Sodium

  • Shrimp meal
  • Fish meal
  • Meat meal
  • Bone meal
  • Molasses
  • Alfalfa meal
  • Wheat husk
  • Rice husk
  • Cotton seed meal
  • Soybean meal
  • Sunflower Seed meal
  • Salt

Biological Functions of Sodium

  • Controlling osmotic pressure and acid-base balance.
  • It also plays a role in the absorption of sugars.

Deficiency signs of Sodium

  • Loss of appetite
  • Reluctance to take food
  • Drowsiness
  • Muscle contraction etc.

Potassium

Potassium is a chemical mineral and its atomic number is 19. It plays role in activating all the functions of the cells of the organism.  It helps in nerve stimulation in the organism and without it, the heart cannot function properly. Potassium is the main positive ion of intracellular fluid and is absorbed directly through the digestive tract, gills, skin and fins. It also meets the needs of fish through supplementary food.

Sources of Potassium

  • Shrimp meal
  • Fish meal
  • Meat meal
  • Bone meal
  • Molasses
  • Wheat husk
  • Rice bran
  • Cotton seed meal
  • Soybean meal
  • Sunflower seed meal
  • Potassium chloride

Biological Functions of Potassium

  • It regulates intracellular osmotic pressure and acid-base balance.
  • It also plays an important role in the synthesis of glycogen and meat and also in the metabolism of glucose.

Chlorine

Chlorine is a chemical mineral with atomic number of 18. It is the main monovalent negative ion of extracellular fluid. It makes up 65% of the total negative ions in blood cells and other extracellular fluids. This material is absorbed directly through the digestive tract, gills, skin and fins when dissolved in water. In addition, the fish get it through supplemental food.

Sources of Chlorine

  • Shrimp meal
  • Fish meal
  • Meat meal
  • Bone meal
  • Molasses
  • Wheat bran
  • Rice bran
  • Cotton seed meal
  • Soybean meal
  • Sunflower Seed meal
  • Rape seed meal
  • Potassium chloride

Biological Functions of Chlorine

  • It maintains osmotic pressure and acid-base balance.
  • It transports oxygen and carbon dioxide.
  • It regulates the pH of digestive juices.

Deficiency Signs of Chlorine

  • Normal growth is abolished
  • Aversion to food
  • Bone loss

Sulfur

It is a chemical mineral and has atomic number of 16. It is found in essential amino acids such as methionine and non-essential amino acids such as cysteine, cysteine and taurine. It is also found in vitamins thiamine and biotin. It plays a role in the production of bile for digestion. It is absorbed directly through the digestive tract, gills, skin and fins.

Sources of Sulfur

  • Fish meal
  • Kelp meal
  • Eggs
  • Feather meal etc.

Biological Functions of Sulfur

  • Sulfur is an essential component of various amino acids (such as methionine and cysteine), vitamins (thiamine and biotin), insulin and shells of crustaceans.
  • It forms heparin, chondroitin, fibrinogen, and taurine.
  • It plays a role in eliminating the toxicity of various aromatic compounds in animals.
  • It accelerates the activity of major enzyme systems such as co-enzyme A and glutathione.

Deficiency Signs of Sulpher

  • Skin problems
  • Inflammation of the muscles
  • Blood circulation is interrupted

Micro Element

Iron(Fe)

Iron is a chemical mineral with atomic number of 26. Iron is an essential element of cellular respiration. It participates in cellular respiration through oxidation and deoxidation and electron transfer. It is present in the body as complex compounds with proteins such as hemoglobin (hemoglobin and myoglobin), heme enzymes (eg. cytochrome, catalase). Iron adequacy and absorption are affected by phosphorus, calcium, phytate, copper and zinc. It is absorbed directly through the digestive tract, gills, skin and fins. The amount of iron required for catfish is 30 mg / kg of food.

Sources of Iron

  • Bone meal
  • Sunflower Seed meal
  • Alfalfa meal
  • Crab crushed
  • Fish meal
  • Poultry droppings
  • Yeast
  • Molasses
  • Rice bran

Biologicl Functions of Iron

  • It is an important component of pigments such as hemoglobin and myoglobin.
  • It is an important components of various enzyme systems such as cytochrome, catalase, peroxidase and various enzymes such as xanthin, aldehyde oxidase and succinic dehydrogenase.
  • It plays a role in transporting oxygen and electrons in the body.
  • It plays an important role in oxidative phosphorylation.

Deficiency Signs of Iron

  • Anemia
  • Decreased physical growth
  • Reluctance to take food.

Zinc(Zn)

It is a chemical mineral and has atomic number of 30. Fish usually absorb zinc from water and supplements. It is absorbed directly through the digestive tract, gills, skin and fins. The presence of zinc in the diet is influenced by phytate, phosphorus, calcium and copper.

Sources of zinc

  • Chicken excrement
  • Wheat husk
  • Crab crushed
  • Yeast