The effect of confinement during lactation on the hypothalamic-pituitary-adrenal axis and behaviour of primiparous sows

S Jarvis*, RB D'Eath, SK Robson, AB Lawrence

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Commercial sows are typically confined in crates before and during parturition and remain there throughout lactation. In various animal species including non-lactating pigs, confinement over similar periods leads to adaptive changes in the HPA axis, consistent with chronic stress. To investigate evidence for chronic stress in lactating sows, primiparous sows (gilts) were kept in behaviourally confining crates with straw bedding (CS, n = 8) or without bedding (C, n = 8) or in larger strawed pens (PS, it = 16) between 5 days before parturition until 29 days postpartum (piglets were weaned on day 28). Behavioural and physiological recordings (Plasma ACTH and cortisol) were taken at intervals (baseline), and CRH injections were given on five occasions (days 2, 8, 15, 22 and 29 postpartum). The PS gilts spent more time in substrate-directed behaviour and lying ventrally, and less time lying laterally and sitting than the two crated treatments (C and CS) throughout lactation. Baseline plasma ACTH and cortisol levels showed no treatment differences, although we confirmed that a diurnal pattern exists, with morning (1000 h) cortisol being higher than later in the day. CRH challenge tests suggested changes in the H:PA axis, consistent with chronic stress, by the end of the lactation period. Cortisol response to CRH tended to be higher in CS than PS across all days, and by day 29 cortisol response to CRH was significantly higher in CS compared to PS and tended to be higher in C than PS. Cortisol/ACTH ratio following CRH challenge also tended to be higher in the crate treatments (C and CS) by day 29. These data suggest that prolonged confinement in farrowing crates may have a negative impact on sow welfare. (c) 2005 Elsevier Inc. All rights reserved.

Original languageEnglish
Pages (from-to)345-352
Number of pages8
JournalPhysiology and Behavior
Volume87
Issue number2
DOIs
Publication statusPublished - 28 Feb 2006

Keywords

  • pigs
  • swine
  • sows
  • parturition
  • lactation
  • confinement
  • chronic stress
  • CRH
  • ACTH
  • cortisol
  • CORTICOTROPIN-RELEASING FACTOR
  • RANGING DOMESTIC PIGS
  • CHRONIC STRESS
  • PLASMA-CORTISOL
  • ADRENOCORTICAL-RESPONSE
  • HOUSING CONDITIONS
  • PARTURIENT SOWS
  • BETA-ENDORPHIN
  • FEMALE PIGS

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