Stress susceptibility in swine, also known as malignant hyperthermia (MH), is a
genetically inherited condition responsible for major economic losses in the swine industry.
Pigs that are heterozygous carriers (Nn) of the genetic mutation in the halothane
gene are exceptionally sensitive to common stressors such as exposure to high temperature,
handling, fighting, breeding, and transport. As a result, pork producers are constantly
searching for means to control stress in swine. Seasonal changes are known to influence the stress response by their action on biochemical peripheral and central pathways, causing the release of pituitary and adrenal hormones and central nervous system monoamines in animals and humans. The
functional relationship between neurotransmitters is greatly affected by the seasons
and was correlated to disturbances in animalsa