Advances in research on the effects of copper on animal immune function
Copper is an essential trace element in the body. It participates in the metabolism of nutrients such as protein, fat, carbohydrates and vitamins in animals, improves the utilization of nutrients in the feed, and is also a component of various enzymes in the body. It is essential for maintaining the normal physiological functions of animals. important. In recent years, copper has been widely used in modern aquaculture as an additive for livestock and poultry feed.
Copper participates in the nutritional regulation of animals and is closely related to the immune function of animals. Copper is involved in the regulation of immune function in the body, and copper deficiency can cause a decline in immune function. The infection test of Salmonella typhimurium found that the copper-deficient rats had higher mortality and shorter survival time than the control group. It may be due to a decrease in the response of the reticuloendothelial system of the copper-deficient mouse to infection. Comparing the effects of the two mice on acute and delayed allergic responses, it was found that copper deficiency did not affect the response of mice to acute allergies, but significantly delayed the response of mice to delayed allergy to ozone. Effects of Escherichia coli endotoxin challenge and infection on kinetic changes in copper in chicken serum, liver, spleen and bursa of Fabricius Experiments have shown that during infection and endotoxin challenge, serum, liver, spleen and bursa The copper content is significantly increased. This proves that copper participates in the immune regulation of the body. In the experimental copper deficiency in rats, the total number of white blood cells decreased, the number of neutrophils decreased, the phagocytic ability of leukocytes, especially the phagocytosis, decreased, and the total concentration of complement in serum decreased. Copper deficiency also reduces T cells, and the ability of lymphocytes to respond to antigens decreases. The level of copper-deficient mouse interleukin is only 40% to 50% of that of normal mice, and it is found that serum copper is elevated in various infections, stimulating and increasing liver synthesis and release of ceruloplasmin, which is beneficial to resist microbial invasion. . The increase of blood copper is mainly related to a leukocyte endogenous substance secreted by neutrophils and macrophages when activated, and the substance reaches the relevant target cells with blood, and plays an important role in immune regulation and sterilization.
1 Effect of copper on animal immune organs
Immune organs can be divided into central immune organs and peripheral immune organs according to the difference in function, function and function. Central immune organs include thymus, bone marrow, and bursa of birds; peripheral immune organs include lymph nodes, spleen, and some lymphoid tissues. Many studies have shown that copper deficiency can affect the development of immune organs and the function of normal immune function. Biochemical and morphological methods were used to observe the growth and development of immune organs in mice with severe copper deficiency, and splenomegaly and thymus shrinkage were found. It has been reported that the thymus and spleen of the copper-deficient rats are atrophied and the thymus weight is reduced. After 7 weeks of low-brown feeding in broilers, it was found that the growth of broilers was hindered, the body weight and the number of lymphocytes in the main lymphoid tissues were reduced, and a small number of degeneration and necrosis of lymphocytes and reticuloendothelial cells appeared. The above studies indicate that copper-raised diets have the effect of promoting spleen development and alleviating thymic degeneration.
2 The effect of copper on animal cell immunity
T cells are the main participants in the cellular immunity of animals and can assist in humoral immunity of B cells. Copper plays an important role in the process of T cell proliferation, helper T cells and B cells. Copper deficiency can alter the components of lymphoid tissue, while T cells are more sensitive to B deficiency than B cells. T cells gradually differentiate into different subpopulations with complementary and cytotoxic functions after they mature in the thymus. Chai Chunyan found that the peripheral lymphocyte subsets of dairy cows increased after copper supplementation. Studies have shown that the number and percentage of CD4+ cells and cD8+ cells in T-lymphocytes of male rats lacking copper are decreased. Copper deficiency results in a decrease in the total number of rodent cD4+ cells, resulting in decreased T lymphocyte function. Bala et al also believe that T cell dysfunction caused by copper deficiency in rodents (mouse) is associated with a decrease in cD4+ subpopulation. The number of spleen cD4+ cells is significantly increased after copper supplementation. Copper supplementation in copper-deficient rats can increase blood lymphocyte non-specific lipase. (ANAE) proportion of staining positive cells. Copper supplementation (250 mg/kg) in aged rats can increase the proportion of ANAE. The above studies showed that after the copper deficiency, the number of T lymphocyte subsets decreased, and the number of T lymphocytes could be increased after copper supplementation, while the effect of copper on ANAE was reported differently. The copper-deficient animal adds copper to the feed to improve the cellular immune function of the animal and enhance the body's resistance.
3 Effect of copper on humoral immunity in animals
Prohaska (1981) and the like first reported that experimental copper deficiency can change the components of humoral immunity, and the feeding of low copper feed to male and female mice can significantly impair the formation of SRBC antibodies. The mice that were raised from low copper at birth were reduced by the activity of ceruloplasmin and the number of antibody cells produced against sheep red blood cells after immunization with sheep red blood cells (SRBC). The relative number of spleen B cells in copper-deficient mice is increased, antibody-producing cell responses are reduced, susceptibility to various microorganisms is increased, and incomplete antibodies are produced. When copper is absent from the feed, the severity of experimental inflammatory damage in the animal is significantly increased and the reactivity of antibody-forming cells is reduced. Dietary copper supplementation (250 mg/kg diet) in aged rats can increase the number of specific antigen (hemolysin) antibody-forming cells (PFC) and antibody titers. The weight of immune organs in mice fed with copper-deficient diet decreased, and the response of B lymphocyte subsets and thymus-like lymphokines to SR-BC stimulation was reduced. Feed the semi-pure and diet 30-day-old calves with copper (1 1.5 mg/kg diet) in serum. The content of IgM and 21d on the antigen-specific antibody of Pasteurella hemolyticus was higher than that of the non-copper group (1.5mg/kg diet), and the plasma ceruloplasmin content was increased. Li Xiuxia's study showed that the serum IgG levels of the mice in the copper-added group were significantly higher than those in the control group, and were significantly higher than the control group after 21 days. A large number of studies have shown that copper significantly promotes humoral immune function in animals and enhances the body's resistance to disease.
4 The effect of copper on non-specific immune function
Non-specific immune systems are innate in animals, including structural barriers such as skin, mucous membranes, and physiological barriers such as pH, O2 levels, and blood proteins that play a role in phagocytosis, swallowing, and inflammatory responses, including many complements, phagocytic cells. And other white blood cells such as natural killer cells (NK cells) constitute the first line of defense of the body. Copper deficiency can cause a decrease in phagocytic activity, damage to the natural immune defense system, and weaker disease resistance and increased susceptibility. When copper is deficient, the number of neutrophils, bactericidal activity, CuZn-S0D activity is significantly reduced, serum anti-neutrophil antibody titer is increased, copper supplementation can increase serum copper content and neutrophils, reduce Or eliminate the anti-neutrophil antibody titer, in the case of copper deficiency, the animals are less resistant to disease and bactericidal, and the function of white blood cells is impaired. The results of the above studies showed that neutrophilic function impairment was observed in severe, mild, and critical copper deficiency, and that copper-deficient animals were less able to resist disease, prone to disease or even death. The number of spleen B cells in the copper-deficient mice increased and the number of T cells decreased, especially in Th cells. K has impaired NK cell activity in copper-deficient rats, while prostaglandin E2 levels are normal, indicating that the decrease in NK activity is not caused by immunosuppression of prostaglandin E2. Li Xiuxia's mouse correction phagocytic index was also higher than the control group, indicating that the addition of copper to the diet can improve the humoral immune function and monocyte phagocytosis in mice. The above studies indicate that non-specific immune function of copper-deficient animals is inhibited and the immune function of the body is reduced.
5 Conclusion
Copper is widely used as a growth promoter in aquaculture production. The proper amount of copper can maintain the body's immune function and promote cellular immunity and humoral immunity. Although copper can promote growth and promote immune function, it is not possible to add copper to the feed without restriction.
Colonial Roof Sheet,Synthetic Resin Roofing Tile,Synthetic Roof Tile,Spanish Roofing Sheet
ZHENHAO BUILDING MATERIALS CO.,LTD , https://www.zhpvctile.com