Causes, consequences and biomarkers of stress in swine: an update

Abstract

BackgroundIn recent decades there has been a growing concern about animal stress on intensive pig farms due to the undesirable consequences that stress produces in the normal physiology of pigs and its effects on their welfare and general productive performance. This review analyses the most important types of stress (social, environmental, metabolic, immunological and due to human handling), and their biological consequences for pigs. The physio-pathological changes associated with stress are described, as well as the negative effects of stress on pig production. In addition an update of the different biomarkers used for the evaluation of stress is provided. These biomarkers can be classified into four groups according to the physiological system or axis evaluated: sympathetic nervous system, hypothalamic-pituitary-adrenal axis, hypothalamic-pituitary-gonadal axis and immune system.ConclusionsStress it is a process with multifactorial causes and produces an organic response that generates negative effects on animal health and production. Ideally, a panel of various biomarkers should be used to assess and evaluate the stress resulting from diverse causes and the different physiological systems involved in the stress response. We hope that this review will increase the understanding of the stress process, contribute to a better control and reduction of potential stressful stimuli in pigs and, finally, encourage future studies and developments to better monitor, detect and manage stress on pig farms.

Re-evaluation of porcine cysticercosis in Nsukka area of Enugu State, Nigeria

“…However, no significant association between sex and the prevalence was established both in the present study and the studies cited above [3,7]. The preponderance of cysticercosis in females could be due to stress and relaxation of immunity associated with hormonal imbalances associated with pregnancy and lactation [10]. Furthermore, females are usually kept longer in pig farms than males, as females are used mainly for production.…”

Identifying Physiological Stress Biomarkers for Prediction of Pork Quality Variation

“…The second stage of stress (long-term, chronic stress) activates the hypothalamic-pituitary-adrenal (HPA) axis, whose activation stimulates the secretion of corticotrophin-releasing factor from the hypothalamus, ACTH from the pituitary gland, and cortisol from the adrenal cortex [20]. The secretion of cortisol into the circulation induces the catabolic activity in peripheral tissues (glycogenolysis, proteolysis, and lipolysis) and anabolic activity in the liver (gluconeogenesis and protein synthesis) in order to increase the blood glucose concentration and provide the energy necessary to cope with the stressor [48]. This can rapidly accelerate muscle glycogenolysis and muscle glycogen depletion due to long-term stress during the preslaughter period, leading to lower production of lactic acid postmortem and resulting in pork with DFD characteristics [20].…”

Association between oropharyngeal microbiome and weight gain in piglets during pre and post weaning life

“…Catecholamines, which include Dopamine (DOP), Epinephrine (EPI) and Norepinephrine (NOR), are secreted during stressful conditions [54]. It is likely that the high ADG piglets have higher appetite levels compared to the low ADG piglets and are therefore more inclined towards aggression and competition for feed with their pen mates leading to higher levels of stress hormones (EPI and NOR) within their circulation [55,56]. Circulating catecholamines are partly secreted into the saliva matrix and this may lead to an accumulation of bacteria, within the oropharynx, that have the ability to degrade catechols.…”