Journal of Animal Science, Vol 78, Issue 9 2399-2411, Copyright © 2000 by American Society of Animal Science

JOURNAL ARTICLE

Administration of ACTH to restrained, pregnant sows alters their pigs' hypothalamic-pituitary-adrenal (HPA) axis

M. F. Haussmann, J. A. Carroll, G. D. Weesner, M. J. Daniels, R. L. Matteri and D. C. Lay Jr
Iowa State University, Ames 50011-3150, USA. donlay@iastate.edu

This study was designed to examine the physiology and behavior of pigs whose dams were snared and then injected with ACTH during gestation. Administration of ACTH to dams during pregnancy has been shown to replicate the effects of prenatal stress in other species. Control sows (n = 8) were given no treatment, whereas the treatment sows (ACTH, n = 8) were immobilized by snaring the snout and then administered an i.v. injection of ACTH (1 IU/kg BW) weekly from 6 to 12 wk of gestation. A pig was killed from each sow at 1, 30, and 60 d of age. The hypothalamus, pituitary gland, adrenal glands, and liver were immediately obtained to determine the amounts of corticotropin-releasing hormone (CRH), beta-endorphin, and mRNA for pro-opiomelanocorticotropin (POMC), the ACTH receptor (ACTH-R), and insulin-like growth factor I (IGF-I). Pituitary corticotrope and somatotrope cell numbers and adrenal cortex-to-medulla area ratios (CORT:MED) were also determined. Pigs' behaviors were recorded at 6 and 8 wk of age. At 75 d of age, a blood sample was taken and a biopsy puncture was created on one pig from each litter, then pigs were stressed by mixing. Blood was sampled every other day for 10 d to determine plasma cortisol concentrations and differential leukocyte counts. Biopsy damage was evaluated for healing. At 1 d of age, control pigs tended to weigh more (P = .09), have a lower expression of ACTH-R mRNA (P = .01) and IGF-I mRNA (P = .01), and a lower CORT:MED (P = .04) than ACTH pigs. At 30 d of age, control pigs had a greater concentration of beta-endorphin (P = .01) and tended to have a lower concentration of CRH (P = .09) and IGF-I mRNA (P = .10) than ACTH pigs. At 60 d of age, control pigs tended to have lighter pituitary glands (P = .08), a lower expression of POMC mRNA (P = .02), and a CORT:MED (P = .003) than ACTH pigs. At 8 wk of age, control pigs performed a higher frequency of belly nosing (P = .07) and oral vice behaviors (P = .01) than ACTH pigs. In response to mixing stress, control pigs had lesser concentrations of plasma cortisol (P = .03) and healed faster (P = .006) than ACTH pigs. Thus, exogenous ACTH and restraint during gestation alters the HPA axis of the sow's offspring, and during stressful situations later in life health, and therefore welfare, may be compromised.

This article has been cited by other articles:

				D. C. Lay Jr, H. G. Kattesh, J. E. Cunnick, M. J. Daniels, K. A. McMunn, M. J. Toscano, and M. P. Roberts Prenatal stress effects on pig development and response to weaning J Anim Sci, June 1, 2008; 86(6): 1316 - 1324. [Abstract] [Full Text] [PDF]

				D. M. Sloboda, T. J. M. Moss, S. Li, D. Doherty, I. Nitsos, J. R. G. Challis, and J. P. Newnham Prenatal betamethasone exposure results in pituitary-adrenal hyporesponsiveness in adult sheep Am J Physiol Endocrinol Metab, January 1, 2007; 292(1): E61 - E70. [Abstract] [Full Text] [PDF]

				E. Kanitz, W. Otten, and M. Tuchscherer Changes in endocrine and neurochemical profiles in neonatal pigs prenatally exposed to increased maternal cortisol. J. Endocrinol., October 1, 2006; 191(1): 207 - 220. [Abstract] [Full Text] [PDF]

				A. Kapoor, E. Dunn, A. Kostaki, M. H. Andrews, and S. G. Matthews Fetal programming of hypothalamo-pituitary-adrenal function: prenatal stress and glucocorticoids J. Physiol., April 1, 2006; 572(1): 31 - 44. [Abstract] [Full Text] [PDF]

				J. N. Marchant-Forde, D. C. Lay Jr., E. A. Pajor, B. T. Richert, and A. P. Schinckel The effects of ractopamine on the behavior and physiology of finishing pigs J Anim Sci, February 1, 2003; 81(2): 416 - 422. [Abstract] [Full Text] [PDF]

				D. C. Lay Jr. and M. E. Wilson Development of the chicken as a model for prenatal stress2 J Anim Sci, July 1, 2002; 80(7): 1954 - 1961. [Abstract] [Full Text] [PDF]