Stress in pigs. II. The influence of vitamins

In stress reactions, with an increase in die secretion of cortisol as occur s with infection, the consumption of ascorbic acid and of,vitamin E is augm ented. The administration of these compounds has an anti-stress effect. The stress susceptibility of halothane-positive pigs is elicited by a defect i n the ryanodine receptor gene and can be eliminated by the breeding of homo zygous halothane-negative pigs. During the transition fr-om pregnancy to la ctation the O-2-consumption ino eases from 1,000 to 2,000 1 per sow and day . This induces an augmentation of the formation of oxygen radicals in the m ammary gland which acts as an oxidative stress to the glandular cells. In t he case of a deficiency in vitamin E and selenium an immuno-suppression dev elops. The development of mastitis and metritis can be prevented by the add ition of 15,000 IU vitamin A, 1,5000 IU vitamin D-3, 60 IU vitamin E, 100 m g ascorbic acid and 0.2 mg selenium per kg of feed in the periparturient pe riod.