Effects of divergent selection upon adrenocortical activity on immune traits in pig

• Published in: BMC veterinary research Vol. 15; no. 1; p. 71
• Main Authors: Hervé, Julie, Terenina, Elena, Haurogné, Karine, Bacou, Elodie, Kulikova, Elizaveta, Allard, Marie, Billon, Yvon, Bach, Jean-Marie, Mormède, Pierre, Lieubeau, Blandine
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 04-03-2019; BioMed Central; BMC
• Subjects: Adrenal glands; Adrenocortical hormones; Adrenocorticotropic hormone; Adrenocorticotropic Hormone - pharmacology; Analysis; Animal experimentation; Animal health; Animal welfare; Animals; B cells; Blood; Blood Cell Count - veterinary; Brain; Chronic exposure; Corticotropin; Cortisol; Cytotoxicity; Divergent evolution; EDTA; Erythrocytes; Experiments; Female; Gene expression; Genetic aspects; Genetic factors; Genetics; Genomics; Glucocorticoids; Health aspects; Hogs; Hormones; Hypothalamic-pituitary-adrenal axis; Hypothalamic-pituitary-adrenocortical axis; Hypothalamo-Hypophyseal System - drug effects; Immunity (Physiology); Inflammation; Inflammatory response; Influence; Life Sciences; Lipopolysaccharides; Lipopolysaccharides - toxicity; LPS challenge; Lymphocytes; Lymphocytes B; Lymphocytes T; Metabolism; Mitogens; Other; Pituitary; Pituitary hormones; Pituitary-Adrenal System - drug effects; Principal components analysis; Robustness; Selection, Genetic; Steroids (Organic compounds); Stress; Suidae; Sus scrofa - blood; Sus scrofa - genetics; Sus scrofa - immunology; Sustainability; Sustainable agriculture; Sustainable development; Swine; Swine breeds; T cells; Tumor Necrosis Factor-alpha - blood; Tumor Necrosis Factor-alpha - metabolism; Tumor necrosis factor-α; Weaning; Genetics; Cortisol; LPS challenge; Robustness; Hypothalamic-pituitary-adrenocortical axis; Immunity; Stress; genetic; stress; cortisol; robustness; hypothalamic-pituitary-adrenocortical axis; immunity
• ISSN: 1746-6148; 1746-6148
• DOI: 10.1186/s12917-019-1809-9

The sustainability of farming and animal welfare requires the reconsideration of current selection schemes. In particular, implementation of new selection criteria related to animal health and welfare should help to produce more robust animals and to reduce anti-microbial use. The hypothalamo-pituitary-adrenocortical (HPA) axis plays a major role in metabolic regulation and adaptation processes and its activity is strongly influenced by genetic factors. A positive association between HPA axis activity and robustness was recently described. To explore whether selecting pigs upon HPA axis activity could increase their robustness, a divergent selection experiment was carried out in the Large White pig breed. This allowed the generation of low (HPA
) and high (HPA
) responders to adrenocorticotropic hormone administration.
In this study, we compared 23 hematologic and immune parameters of 6-week-old, HPA
and HPA
piglets and analysed their response to a low dose of lipopolysaccharide (LPS) two weeks later. At six weeks of age, HPA
piglets displayed greater red blood cell and leucocyte number including CD8α
γδ cells, cytotoxic T lymphocytes, naive T helper (Th) cells and B lymphocytes as compared to HPA
individuals. The ability of blood cells to secrete TNFα in response to LPS ex vivo was higher for HPA
pigs. At week eight, the inflammatory response to the LPS in vivo challenge was poorly affected by the HPA axis activity.
Divergent selection upon HPA axis activity modulated hematologic and immune parameters in 6-week-old pigs, which may confer an advantage to HPA
pigs at weaning. However, HPA
and HPA
piglets did not exhibit major differences in the parameters analysed two weeks later, i. e. in 8-week-old pigs. In conclusion, chronic exposure to high cortisol levels in HPA
pigs does not negatively impact immunity.