What are the nutrient requirements of pigs?
Vitamins are a special class of nutrients essential for maintaining the normal life and growth of pigs. Most vitamins must be obtained from feed, and the required amount is very small, but physiologically they play an important role in regulating and controlling metabolism. They also have disease resistance and immune functions. They are mainly used for pig growth, health, feed conversion, reproduction and improving the survival rate, etc. If they are lacking in the body, a series of vitamin deficiency diseases will be caused. There are more than 20 kinds of vitamins, and their chemical structures are all different. They are generally divided into two categories: one is fat-soluble vitamins, such as vitamin A, vitamin D, vitamin E and vitamin K, etc.; the other is water-soluble vitamins, such as the vitamin B group and vitamin C, etc.
(1) Fat-soluble vitamins
Vitamin A (anti-xerophthalmia factor): It is related to the regeneration of rhodopsin in the retina of the eye, so it has the functions of protecting vision and the normal physiological function of the optic nerve, promoting bone growth, enhancing resistance and immunity, and maintaining the integrity of epithelial tissue and the health of the mucous membranes of the digestive tract and respiratory tract, etc. When vitamin A is lacking, pigs suffer from night blindness, keratinization of epithelial tissue, and reduced secretions. When the deficiency is severe, the mucous membranes of various organs of pigs are damaged, disease resistance is reduced, and inflammation of the respiratory tract, digestive tract and urogenital tract, etc. is caused, and it may even cause stillbirth and miscarriage.
Pigs can directly obtain vitamin A from animal feed, and can only obtain carotene from plant feed, and carotene is converted into vitamin A in the pig's liver before it can be utilized by the pig's body.
2. Vitamin D (anti-rickets factor): It can promote the absorption of calcium and phosphorus in the intestinal tract, regulate calcium and phosphorus metabolism and the content of calcium and phosphorus in the blood, and promote the deposition of calcium and phosphorus in bones. There are vitamin D2 and D3. Ergosterol in plants can be converted into vitamin D2 after being irradiated by ultraviolet rays in sunlight, and dehydrocholesterol under the skin of pigs can be converted into vitamin D3 after being irradiated by ultraviolet rays in sunlight. These two kinds of vitamin D have exactly the same effect on pigs. If some sun-dried green hay meal is added to the feed, pigs can obtain some vitamin D2. Large-scale pig farms generally use a variety of compound vitamins, and the vitamin D contained in them can meet the needs of pigs.
3. Vitamin E (anti-infertility factor): It belongs to the most active tocopherol among phenolic compounds, has a strong oxidizing effect, and should be stored sealed. It can maintain the normal reproductive function of pigs and the normal physiological state of muscles and peripheral blood vessels, has the function of maintaining heart muscle health and promoting cell nucleus metabolism, and cannot be replaced by other vitamins. Lack of vitamin E leads to pig scorched muscle disease, muscle atrophy, myocardial degeneration, hydropericardium, reproductive dysfunction in sows, poor testicular development in boars, etc. Pigs need 2 to 34 international units per day in their diet. Cereals and green feed contain more vitamin E.
(2) Water-soluble vitamins
1. Vitamin B1 (thiamine): It is the coenzyme active factor of many cellular enzymes and participates in the oxidative decarboxylation reaction of ketone substances in the process of carbohydrate metabolism. Lack of this vitamin means that pyruvate cannot enter the oxidation process in the tricarboxylic acid cycle, causing excessive accumulation of pyruvate in the blood, brain and muscles, resulting in neurological disorders, difficulty in movement, and muscle degeneration. Bran and green hay contain more vitamin B1. Pigs should be supplied with 0.3 to 3 international units per day in their diet.
2. Vitamin B2 (riboflavin): It is a component of cellular flavin enzymes, and also a component of egg cell flavin, often appearing in the form of a flavin enzyme prosthetic group, and participates in the metabolism of proteins, fats and nucleic acids as well as biological oxidation processes. Lack of this vitamin causes metabolic disorders, lack of vitality in cells and eggs, slow growth of pigs, bone damage and decreased reproductive capacity. Feed yeast, fish meal, bran, high-quality hay and green feed contain more of it. Pigs need 0.6 to 6 international units per day.
3. Vitamin B12: It is a regulatory substance for pig blood metabolism, promotes blood formation and metabolism, can enhance the activity of niacin and amino acid synthase, and is beneficial to protein metabolism. Lack of vitamin B12 mainly causes anemia, hind limb movement disorders, and decreased reproductive capacity. Pigs need 4 to 29 micrograms per day in their diet.
Water is an important component of the various tissues and organs that make up the pig's body. In physiological activities, water plays an important role in the digestion, absorption, metabolism, waste excretion, blood circulation and body temperature regulation of nutrients. Lack of water causes loss of appetite, low feed utilization, interferes with all processes in the body, and affects the normal exertion of productivity; severe water shortage can even cause the death of pigs, especially piglets,
The drinking water volume of pigs changes with seasonal temperature, with a large amount in summer and a small amount in winter. The drinking water of pigs must be guaranteed.