Stress in pigs: I - A survey of forms of stress and its effects

Three forms of stress reactions are manifested by pigs. First, in Selye's r eaction, the secretion of ACTH and cortisol increases for a period of time. This is, for example, induced by transport and bacterial endotoxins. The s econd is as a result of the genetical defect in the ryanoidine receptor (a Ca-ion channel). Such,,stress susceptible << pigs develop malignant hyperth ermia after continuous stress, such as that induced by transport under heat conditions, also after the slaughter of these genetically susceptible pigs PSE meat results. The third is a biochemical dysfunction in which, at the start of lactation, Oz consumption and the formation of reactive OI-molecul es (OI-radicals) in the mammary gland increase. These are destructive for c ells and produce an oxidative stress. Ascorbic acid and Vitamin E are neces sary for the decay of 0(2) radicals.