1、Vitamin E and stress response Stress (stress) refers to the sum of nonspecific response to external or internal very stimuli, caused by stress factors known as stress factors or stressors (stressor). The mobilization of body tissues and organs to deal with, to adapt to the series of responses to str
2、ess stimuli showed that general adaptation syndrome (GAS). It is organized as follows: the physiological changes of adrenocorticotropic hormone (ACTH) production and increased release of, anterior pituitary enlargement. adrenal hyperplasia enlargement. due to increased release of corticosterone and
3、adrenal cholesterol secretion decreased. poult reaction are most sensitive to tissue lymph, thymus, bursa of Fabricius and spleen atrophy； adult chicken because of the influence of gonadal steroids, only the bursal atrophy. The white blood cell changes, showed lymphopenia, heterophils increased. Inc
4、rease the blood concentration of citric acid. The growth retardation, decreased body weight. The modern intensive livestock production, automation, in order to maximize the level of livestock and poultry production, increase economic efficiency, to livestock and poultry as production machine. The pr
5、oduction process and technical measures adopted are often contrary to the animals physiological needs. The resulting stress leads to decrease of slow growth, reduced fecundity, productivity and product quality variation, the immunity of livestock and poultry, causing great harm to livestock and poul
6、try production. In the modern industry production, vaccines for the prevention, control and eradication of infectious diseases of livestock play an extremely important role, immunization hand to protect the body against animal pathogens, on the other hand, as a kind of special stress factor resultin
7、g in immunological stress, some damage to the body, the damage is not only affect the growth and development and the production performance of livestock and poultry, and may cause a few animal death. 1,the stress response mechanism The mechanism of stress response is a complex process, according to
8、the Canadian pathologist Hans Selye stress theory, from the stress state of view, can be divided into three periods: alert period (emergency reaction stage), resistance (resistancestage) and failure stage (exhaustion stage). The alert period. The body has not yet received the adaptation period, the
9、body is early response to stressors. According to the physiological and biochemical changes of different, this period can be divided into shock and reverse shock phase. Shock phase as temperature and a decrease in blood pressure, blood concentration, inhibit the nervous system, muscle tension decrea
10、sed, and then to tissue degradation, hypochloremia, hyperkalemia, gastrointestinal ulceration, body resistance is lower than the normal level. Shock is sustainable for a few minutes to 24 hours. The stress response to enter the shock phase, the defense has been strengthened, increased blood pressure
11、, serum sodium and serum chloride increased, blood potassium reduced, blood glucose increased, catabolism strengthen, atrophy of thymus, spleen and lymph system, eosinophilic leukocytes and lymphocytes decreased, adrenal hypertrophy, improve the total resistance, even higher than that of normal leve
12、l. In the period of resistance. The body to overcome the stress source and get fit, many performance and panic reaction on the contrary, the new supersedes the old. To be normal, assimilation dominant, white blood cells and adrenal cortex hormone content tended to be normal, systemic non-specific re
13、sistance increased to higher than normal level. The failure stage. Performance is like alert period, but the reaction degree increased dramatically, appear all sorts of malnutrition, adrenal cortex although hypertrophy, but cannot produce the necessary hormone, dissimilation again dominated, rapid w
14、eight loss, then the reserve depletion, the new supersedes the old. The emergence of irreversible change, to adapt to function damage, leading to death. 2. The clinical symptoms of stress Because the source of stress intensity, duration, chicken breed, age and nutritional status, stress the variety
15、of clinical symptoms, basically divided into the following three types. 2, 1 sudden death of stress syndrome Chicken in the catch, frightened, vaccine reaction or extrusion strong stressor stimulation, not showing any symptoms, sudden death. This is due to strong stimulation, sympathetic - adrenal s
16、ystem activity, caused by shock or circulatory collapse and sudden death. 2, 2 acute stress syndrome Mainly due to stress caused by long time strong stimulation, common are the following: heat stress syndrome. The temperature is too high, the hot weather, the crowded transportation, water, chicken b
17、ody heat too much, difficult heat dissipation, the performance difficulty breathing, mouth breathing, heart rate, body temperature, crown beard flushing cyanosis, muscle tremors, foaming at the mouth, chicken prone to acute bronchial pneumonia and death. convulsive stress. Fight, noise, capture, tra
18、nsport, mixing frightened group process, show head feathers ruffled, panic, tension, hide, loss of appetite, and even waste vast, gain weight, laying rate drop, a few chicken death. cannibalism. Rearing density (crowding stress), the high temperature (heat stress), the light is too strong (light str
19、ess), skin trauma and hemorrhage (stress), scabies or other external parasites (such as itching stress) stress stimulation, can cause stress reaction of pecking； protein, vitamin, mineral deficiency nutritional deficiency of cannibalism is a stress response. The clinical manifestations of feather pe
20、cking, pecking anal, peck peck, peck toe, meat eggs. you disease. Chicken every day within 2h after the onset of disease, call you. You are chicken to the nest on time, so when the dim and dark house, chicken on a particularly intense, sharp heap, trampling each other, extrusion stress lethal. The m
21、uscular stomach injury. Muscle of gastric mucosa erosion or ulcer of the occurrence of chicken. 2, 3 chronic stress syndrome By the stress intensity of the long-term repeated stimulation. For example, the lack of nutrition, competition among individuals, raising no rules, and hunger and satiety, She
22、rwin sometimes hot and sometimes cold, bacterial, fungal infection, the body continues to make adaptation efforts, forming the cumulative effect of adverse effect of chicken, appetite, causing growth retardation, weight reduction, laying rate drop, the hatching rate. Weakened immune response and def
23、ense capabilities, easy to secondary infection of other diseases. 3. Stress damage of chicken Normal chicken has the ability to cope with stress from damage, but this ability is limited. The cumulative effect of stress factor or stress beyond protecting threshold, will change from the physiological
24、process for the pathological process. Endanger mainly have the following aspects. 3.1Production performance Stress, protein, carbohydrate, fat and increased catabolism, produce more energy to meet the immediate needs, such as heat, accelerated breathing, heartbeat, and fled, and these nutrients for
25、growth, the original weight, immune function, so the indirect effects of the production performance of chickens, performance poult dysplasia, survival rate is low； poultry and egg laying rate drop, egg quality is low, eggs, small deformation, eggshell thinning, brittle, surface roughness, broken egg
26、 rate, hatching egg fertilization rate； poultry growth, body weight decreased, the meat quality is poor, low feed reward. 3, 2 produce stress syndrome Manifestations of renal cortical hypertrophy, lassitude, rapid heartbeat, high blood pressure, loss of appetite, reduced sexual function, slow growth
27、, the most serious from fear of death. 3, 3 immune resistance Chicken in the stress, the increase in the secretion of epinephrine, make blood lymphocytes decreased, at the same time, because of increased protein catabolism, used to produce immunoglobulin raw material is relatively reduced, the vacci
28、ne, antibody formation was reduced, low antibody level in the body, can not achieve the desired effect of the immune. 3, 4 to induce various diseases Stress not only make chicken lower only specific immunity in chickens, and non - specific resistance is generally reduced, easy to induce a variety of
29、 diseases, such as bluecomb disease, chronic respiratory disease, infectious coryza, aspergillosis, bursitis, fowl cholera, ulcerative enteritis. 4, immunological stress Immunological stress animal is the animal vaccination appear individual allergic, a handful of animal body temperature, some anima
30、l anorexia, metabolism, growth, feeding cycle extension phenomenon. Generalized immune also known as immune challenge in immunology, which inject antigen to stimulate the immune response. In the animal life, there are many factors (including infection, trauma and tumor) can cause immune stress. In t
31、he immunity during stress, cytokines especially produced by monocytes and macrophages in the inflammatory cytokines IL-1, IL-6 and TNF- mediated inflammation response system, if have a fever, loss of appetite, also plays a role in nutrient redistribution agent, can be used in the growth and skeletal
32、 muscle protein deposition of nutrients for related process to maintain the immune response. The amount of inflammatory cytokines produced in favor of the body against infection, but produces too much will cause varying degrees of damage to the body. Especially the TNF- causes pathological reaction
33、in inflammatory conditions or inflammatory diseases. The study found that can activate the immune system of the material are likely to stimulate the body to produce immunity stress (Kelly, 1998). The immune system has the ability to give priority to the use of nutrients, when the animal immune stress, immune system activation, release of cytokines (CK, CK) regulate metabolism process, affecting the growth of demand and the mode properties and nutritional needs. Research shows that, the change of stress is mainly mediated by CK. Webel (1998) to the pig
