1 The effect of insufficient or excessive vitamins on poultry

1.1 Nutritional characteristics of vitamins

Vitamins are a class of low molecular organic compounds necessary for various physiological functions of poultry and special poultry. It plays an important role in regulating and controlling the metabolism of poultry, improving the performance of poultry and the utilization of feed.

At present, there are at least 15 kinds of vitamins added to the feed, which can be divided into two categories: fat-soluble vitamins and water-soluble vitamins, namely VA, VD, VK, VE, VB1, VB2, VB6, VB12, niacin, pantothenic acid, choline, Folic acid, biotin, VC, etc. A variety of vitamins are part of the coenzyme or prosthetic group and participate in various metabolisms of the body.

All kinds of green and green feeds are rich in vitamins. Under the conditions of extensive feeding, because the birds can feed a large amount of green and green feed, vitamins are generally not lacking. However, with the substantial increase in the scale of poultry production, especially the commercialization and intensification of poultry feeding methods such as commercial laying hens, broilers, meat ducks, meat pigeons, crickets and crickets, these poultry are separated from sunlight, soil and green. Natural nutrients and environmental conditions such as feed can only meet the needs of poultry by relying on the nutrient source in the feed. On the other hand, poultry under intensive production conditions are particularly prone to vitamin deficiency. High-density modernized poultry and poultry production can generate a lot of stress, increase the vitamin requirements of poultry, and under normal circumstances, poultry has higher vitamin requirements than other animals, so it is necessary to supplement industrially produced vitamins.

1.2 The effect of vitamin deficiency on poultry

In the production of poultry, the lack or insufficient addition of any kind of vitamin can lead to metabolic disorders in the bird and cause various diseases. If the VA is insufficient or lacking, the young birds will have growth stagnation, weight loss, and feathers. The severely deficient chicks will have movement disorders; the laying hens will have a lower egg production rate and hatching rate, and blood spots in the eggs. Symptoms of increased incidence and severity. Lack of VE can cause brain softening in young birds, exudative quality of young birds, and muscle necrosis in young birds and adult birds. Listed feed Yingcai. The lack of any kind of vitamins such as choline, niacin, VB6, biotin and folic acid in poultry and young birds can cause short bones of the humerus. Lack of choline can cause avian fatty liver syndrome. Lack of folic acid can also cause anemia, leukopenia, feather discoloration, cervical paralysis, high embryo mortality, and reduced hen egg production.

In production practice, due to a wide range of feed sources, some of the vitamins in the feed may be lost during processing, transportation, storage, and changes in feed ingredients and environmental conditions. For example, in the process of processing pellets, some vitamins are oxidatively decomposed by heat, which destroys their activity; if there is whitefly in the feed, it can reduce the absorption of VA and VD by birds; the feed containing mycotoxins increases the solubility of fat. The amount of vitamins and other vitamins (such as biotin, folic acid).

Studies have shown that adding vitamins slightly higher than the feeding standard can achieve optimal immune status in birds. Currently used corn--bean meal type diet, special attention should be paid to the addition of VA, VD3, VE, VK, riboflavin (VB2), niacin, pantothenic acid, VB12 and choline. For caged poultry, more VK and B vitamins should be added than ground poultry.

In the summer, the addition of B vitamins, VC and VE can alleviate the heat stress of birds. In addition, the addition of B vitamins and VC can also increase the growth rate of broiler chickens, increase egg production, egg weight and eggshell quality. Adding VE also has the effect of improving immunity and reducing mortality. However, it should be reminded that the "poultry multivitamin" sold in the market does not contain choline chloride and VC, and if the bird needs it, it should be added separately. 1.3 adverse consequences of excessive vitamin supplementation

Excessive vitamin supplementation or long-term overfeeding can have undesirable consequences. In particular, some fat-soluble vitamins cannot be added in excess. Practice has shown that VA, VD and VK3 excess have toxic effects on poultry. If the amount of VA added exceeds the normal amount by more than 50 times, the chicken exhibits depression, gait instability, decreased feed intake, and complete refusal. Studies have reported that excessive VA will cause the bone growth plate of chicks and ducklings to narrow. If the VD level in the feed diet is as high as 4 million IU/kg of feed or higher, it can cause dystrophic calcification of the renal tubule and cause damage to the kidney; moderate VD excess can cause the calcareous surface of the eggshell surface of the laying egg. The incidence of the knot is increased, which affects the quality of the eggs. Therefore, when adding such vitamins, avoid excessive.

2 The impact of insufficient or excessive minerals on poultry

2.1 Nutritional characteristics of minerals

Minerals are an important component of poultry tissues and cells. It is involved in regulating the constant penetration of body fluids, activating digestive enzymes, maintaining the acid-base balance of the blood and the normal excitability of nerves and muscles, as well as the absorption and utilization of other nutrients in the body. Therefore, it plays an important role in the growth, reproduction and nutrient metabolism of poultry.

Mineral elements in poultry feed can be divided into two broad categories. One type is a constant element, which is calcium, phosphorus, magnesium, potassium, sodium, sulfur, chlorine. Among them, calcium and phosphorus are the most important mineral elements in the formation of bones, and they are also extremely scarce in poultry production. The other type is trace elements. At present, most of the necessary trace elements are iron, copper, zinc, cobalt, manganese, iodine, selenium, fluorine, molybdenum, chromium, nickel, vanadium, tin, silicon and so on. The trace elements that need to be supplemented in poultry feed diets are manganese, iron, copper, cobalt, iodine, selenium, etc. They are the life elements of poultry organisms. For intensively raised poultry, these trace elements are even more than vitamins. Have dependencies.

2.2 Poor consequences of insufficient or excessive minerals

Mineral elements cannot be transformed or replaced in poultry. If the minerals in the feed are insufficient or lacking, it will affect the normal growth and reproduction of the birds and reduce the utilization of feed. For example, lack of calcium and phosphorus, poultry manifestations of dysplasia, osteoporosis, keel bending, prone to rickets, osteoporosis in adult birds, calcium deficiency in laying eggs will produce thin shell eggs or soft shell eggs. Zinc-deficient poultry showed loss of appetite, growth retardation, poor feather growth, short humerus, and enlarged joints; egg laying showed delayed sexual maturity, reduced egg production, reduced hatching rate, and more dead embryos. The selenium-deficient poultry showed growth retardation, fat indigestion, and white muscle disease, exudative quality, pericardial effusion, and pancreatic atrophy and fibrotic lesions. The lack or deficiency of manganese in the feed diet will reduce the weight loss, egg production rate and hatching rate of adult poultry; it will also cause bone dysplasia in young birds, short bones, movement disorders and growth retardation.

However, excessive addition of mineral elements can have undesirable consequences. Feeding 8-20 weeks old hens in high calcium diets can cause kidney disease and visceral gout. Poisoning is more likely to occur if the trace elements are not properly added. Excessive amounts of selenium can hinder the growth of birds, delay sexual maturity, and fluffy feathers. It has been shown that the selenium content in the diet of laying hens exceeds 5 mg/kg, which will reduce the hatching rate and abnormality of the embryo. The high zinc content in the laying hen diet can cause the hen to change feathers and the egg production to drop sharply. Excessive intake of copper can also cause abnormalities in the stomach and stomach of the bird. If the feed diet is supplemented with 2000 mg/kg of copper, it will cause atrophy of the muscles of the birds and bleeding under the stratum corneum. Therefore, mineral elements in poultry feed diets must be reasonably added in accordance with nutritional standards to prevent under or excess.