The impact of environmental factors on the milk ejection and stress of dairy cows

摘要: Farm breeding of cattle is organized so that the animals are kept in a controlled environment (an closed corner, feeding time, milking workers), where daily animal encounter with familiar sounds, smells, movements and equipment. Any positive or negative change causes certain physiological reactions on it. Negative stimuli (relocation, new technological activities, unidentified sounds people) disrupt homeostasis lead them into state stress. During stress appears central inhibition milk ejection from alveoli udder, causing its incomplete emptying which could to pathological changes. In stressful situation, there connection between nervous (SA system), endocrine (HPA-axis) immune system. Stimuli outside were obtained through sight, hearing, smell touch, leading nerve impulses then activate system (increased levels cortisol, β-endorphin, adrenaline, reducing oxytocin blood), whose actions over long time decline response susceptibility disease. Many studies suggest an association situations (first primiparious cattle, changes), but very principle not fully understood. Some indicate endogenous opioids (β-endorphin) catecholamines (adrenalin) ejection, however, still no clear evidence plenty do this area.