The effect of active immunization against adrenocorticotropic hormone on cortisol, ß-endorphin, vocalization, and growth in pigs

C. Lee, L.R. Giles, W.L. Bryden, J.A. Downing, D.C. Collins, Peter Wynn

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Because the poor growth performance of intensively housed pigs is associated with increased circulating glucocorticoid concentrations, we investigated the effects of glucocorticoid suppression by inducing a humoral immune response to ACTH on physiological and production variables in growing pigs. Grower pigs (28.6 ± 0.9 kg) were immunized with amino acids 1 through 24 of ACTH conjugated to ovalbumin and suspended in diethylaminoethyl (DEAE) dextran-adjuvant or adjuvant alone (control) on d 1, 28, and 56. The ACTH-specific antibody titers generated suppressed increases in cortisol concentrations on d 63 in response to an acute stressor (P = 0.002; control = 71 ± 8.2 ng/mL; ACTH-immune = 43 ± 4.9 ng/mL) without altering basal concentrations. Plasma ß-endorphin concentrations were also increased (P < 0.001) on d 63 (control = 18 ± 2.1 ng/mL; ACTH-immune = 63 ± 7.3 ng/mL), presumably because of a release from negative feedback on the expression of proopiomelanocortin in pituitary corticotropes. Immunization against ACTH did not alter ADG (P = 0.120; control = 1,077 ± 25; ACTH-immune = 1,143 ± 25 g) or ADFI (P = 0.64; control = 2,719 ± 42; ACTH-immune = 2,749 ± 42 g) and did not modify behavior (P = 0.681) assessed by measuring vocalization in response to acute restraint. In summary, suppression of stress-induced cortisol responses through ACTH immunization increased ß-endorphin concentrations, but it did not modify ADG, ADFI, or restraint vocalization score in growing pigs.
Original languageEnglish
Pages (from-to)2372-2379
Number of pages8
JournalJournal of Animal Science
Volume83
Issue number10
Publication statusPublished - 2005

Fingerprint Dive into the research topics of 'The effect of active immunization against adrenocorticotropic hormone on cortisol, ß-endorphin, vocalization, and growth in pigs'. Together they form a unique fingerprint.

  • Cite this