title: Effects of social support on glucocorticoid sensitivity of lymphocytes in socially deprived piglets.
abstract: There is growing evidence that social support given by a conspecific attenuates stress responses of a socially deprived animal. We hypothesized that the presence of a familiar social partner modulates the effectiveness of social buffering as assessed by an altered glucocorticoid sensitivity of immune cells. The current study investigated the effects of a 4-h social deprivation procedure on stress hormone responses and immune cell functions in 7-, 21- and 35-day-old piglets (52 males and 56 females). Within each of the three age categories, nine piglets were deprived of their mother and littermates either alone or with a familiar or unfamiliar age-matched piglet. Compared to non-deprived controls, piglets that were alone displayed significant increases in plasma adrenocorticotropic hormone and cortisol concentrations, and all socially deprived piglets showed a greater in vitro proliferative response of peripheral blood mononuclear cells (PBMCs) to lipopolysaccharide (LPS)-stimulation than controls. Concanavalin A (ConA)-induced in vitro proliferation was not affected by social treatment. Additionally, both the ConA- and LPS-stimulated PBMCs from piglets that experienced any of the deprivation treatments were more resistant to the inhibitory effects of cortisol than PBMCs from the controls in each of the three age categories. Irrespective of the mitogen used, the presence of an age-matched conspecific during deprivation attenuated the dose-dependent cortisol resistance. Here, familiarity between the piglets clearly improved the effectiveness of social support in an age-dependent manner. Collectively, our findings emphasize the benefits of social partners regarding stress coping abilities, with positive implications for animal welfare and health.
authors.affiliation: a Institute of Behavioural Physiology, Leibniz Institute for Farm Animal Biology (FBN) , Dummerstorf , Germany ;
authors.forename: Margret
authors.initials: M
authors.lastname: Tuchscherer
authors.affiliation: a Institute of Behavioural Physiology, Leibniz Institute for Farm Animal Biology (FBN) , Dummerstorf , Germany ;
authors.forename: Ellen
authors.initials: E
authors.lastname: Kanitz
authors.affiliation: b Institute of Genetics and Biometry, Leibniz Institute for Farm Animal Biology (FBN) , Dummerstorf , Germany ;
authors.forename: Armin
authors.initials: A
authors.lastname: Tuchscherer
authors.affiliation: a Institute of Behavioural Physiology, Leibniz Institute for Farm Animal Biology (FBN) , Dummerstorf , Germany ;|c Behavioural Sciences, Faculty of Agricultural and Environmental Sciences , University of Rostock , Rostock , Germany.
authors.forename: Birger
authors.initials: B
authors.lastname: Puppe
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D006854:Hydrocortisone / Q000097:blood*; D007963:Leukocytes, Mononuclear / Q000187:drug effects; D008070:Lipopolysaccharides / Q000494:pharmacology; D008214:Lymphocytes / Q000166:cytology* / Q000187:drug effects; D008297:Male; D012919:Social Behavior; D012934:Social Isolation; D013315:Stress, Psychological / Q000097:blood*; D013552:Swine
chemical_list: D008070:Lipopolysaccharides; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone
keywords: Animal welfare; HPA axis; buffering; cortisol resistance; familiarity; immune cells