Pituitary-Adrenal Axis Responses to Routine Management Procedures in Sheep (Ovis aries)

Authors

  • Esterina Fazio Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, 98168 Messina, Italy.
  • Pietro Medica Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, 98168 Messina, Italy.
  • Cristina Cravana Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, 98168 Messina, Italy.
  • Adriana Ferlazzo Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, 98168 Messina, Italy.

DOI:

https://doi.org/10.22456/1679-9216.81164

Keywords:

sheep, restraint, shearing, ACTH, cortisol.

Abstract

Background: Shearing is considered as a stressful factor in sheep, capable of causing some behavioural changes including variations of body condition and hormonal and haematochemical parameters. On these basis, circulating ACTH and cortisol concentrations were determined in sheep before and after exposure to aversive stimuli in order to evaluate the potential use of these hormones to objectively measure physical and mental stress responses to isolation, restraint and shearing.

Materials, Methods & Results: Forty Pinzirita sheep, used as experimental group, were evaluated in baseline conditions, 24 h before isolation, restraint and shearing (T0), after isolation (T1), after restraint and shearing (T2), by taking into account the influence of previous shearing experience (just shorn). A control group of forty sheep (intact) was evaluated in baseline condition (T0). According to previous experience the experimental subjects were divided in two groups, respectively group A represented by 20 sheep (10 males and 10 females), aged 1-2 years, without previous shearing experience (intact); and group B represented by 20 sheep (10 males and 10 females), aged older than 2 years, previously exposed to shearing (just shorn). A control group C of 40 sheep splitted into two sub-groups represented by 10 intact males and 10 intact females, aged 1-2 years, and 10 males and 10 females just shorn, aged older than 2 years, was evaluated in baseline conditions (T0). Blood samples were collected 24 h before experimental practices (T0: 08:00 h), after 1 h after of isolation (T1) and after restraint and shearing, around an average of 5 min (T2). All samples were taken in quiet conditions by the same operator. Serum ACTH concentrations were assayed by a commercial radioimmunoassay (RIA). Serum cortisol concentrations were assayed by amplified Enzyme Immunoassay (EIA). Two-way RM ANOVA showed a significant effect of husbandry procedures on ACTH changes, with higher ACTH and cortisol concentrations of just shorn than intact males (F = 15.76;
 P < 0.0001) and females (F = 17.34; P < 0.0005), and on cortisol changes, with higher cortisol concentrations of just shorn than intact males (F = 6.54; P < 0.01) and females (F = 22.66; P < 0.0001).

Discussion: The highest ACTH and cortisol values after isolation, with an appreciable increase especially after restraint and shearing in just shorn sheep, showed that the previous shearing exposure could not induce a habituation to the stimulus, probably promoting a larger release of ACTH and cortisol hormones, so inducing an early and marked coping response to stress in just shorn specimens. Thus, it would appear that different ACTH and cortisol responses of sheep with or without previous shearing experience over the study period resulted in some significant differences when exposed to isolation, restraint and shearing, probably due to changes in pituitary-adrenal axis reactivity. Nevertheless, it is possible  to interpret the increase in ACTH and cortisol concentrations related to intrinsic endocrine control mechanisms as an increase due to a rise in the stressful stimulus or coping response. The magnitude of ACTH and cortisol changes following isolation, restraint and shearing suggests that measurements of both hormones are useful in assessing husbandry procedures stress in sheep, with marked elevations in just shorn sheep, indicating that experience can induce an early much larger coping response to stressful practice of shearing.

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References

Boissy A., Bouix J., Orgeur P., Poindron P., Bibè B. & Le Neindre P. 2005. Genetic analysis of emotional reactivity in sheep: effects of the genotypes of the lambs and of their dams. Genetics Seection Evolution. 37(4): 381-401.

Coulon M., Lévy F., Ravel C., Nowak R. & Boissy A. 2014. Mild effects of gestational stress and social reactivity on the onset of mother-young interactions and bonding in sheep. Stress. 26(6): 1-40.

da Costa A.P., Leigh A.E., Man M.S. & Kendrick K.M. 2004. Face pictures reduce behavioural, autonomic, endocrine and neural indices of stress and fear in sheep. Proceedings: Biological Sciences. 271(1552): 2077-2084.

Doyle R.E., Lee C., Deiss V., Fisher A.D., Hinch G.N. & Boissy A. 2011. Measuring judgement bias and emotional reactivity in sheep following long-term exposure to unpredictable and aversive events. Physiology & Behavior. 102(5): 503-510.

Fazio E., Medica P., Alberghina D., Cavaleri S. & Ferlazzo A. 2005. Effect of long-distance road transport on thyroid and adrenal function and haematocrit values in Limousin cattle: Influence of body weight decrease. Veterinary Research Communications. 29(8): 713-719.

Fazio E., Medica P., Cravana C. & Ferlazzo A. 2011. Adrenocortical response of jennies to milking stress. Livestock Science. 137(1-3): 278-281.

Fazio E., Medica P., Mignacca S., Cravana C. & Ferlazzo A. 2011. Haematological and cortisol changes after 3 h road journey in sheep. Journal of Animal and Veterinary Advances. 10(19): 2487-2492.

Fazio E., Medica P., Cravana C., Cavaleri S. & Ferlazzo A. 2012. Effect of temperament and prolonged transportation on endocrine and functional variables in young beef bulls. Veterinary Record. 171(25): 644.

Fazio E., Medica P., Cravana C. & Ferlazzo A. 2014. Short- and long-term effects of weaning on adrenocortical and functional response of lambs. Acta Scientiae Veterinariae. 42: 1193.

Ferlazzo A., Medica P., Cravana C. & Fazio E. 2012. Circulating β-endorphin, adrenocorticotropin, and cortisol concentrations of horses before and after competitive show jumping with different fence heights. Journal of Equine Veterinary Science. 32(11): 740-746.

Foreman H. & Ferlazzo A. 1996. Physiological responses to stress in the horse. Pferdeheilkunde. 12(4): 401-404.

Hargreaves A.L. & Hutson G.D. 1997. Handling systems for sheep. Livestock Production Science. 49(2): 121-138.

Hargreaves A.L. & Huston G.D. 1990. Some effects of repeated handling on stress responses in sheep. Applied Animal Behaviour Science. 26(3): 253-265.

Hashizume T., Haglof S.A. & Malven P.V. 1994. Intracerebral methionine-enkephalin, serum cortisol, and serum β-endorphin during acute exposure of sheep to physical or isolation stress. Journal of Animal Science. 72(4): 700-708.

Hasiec M., Tomaszewska-Zaremba D. & Misztal T. 2014. Suckling and salsolinol attenuate responsiveness of the hypothalamic-pituitary-adrenal axis to stress - focus on catecholamines, CRH, ACTH, cortisol and prolactin secretion in lactating sheep. Journal of Neuroendocrinology. 26(12): 844-852.

Hernandez C.E., Matthews L.R., Oliver M.H., Bloomfield F.H. & Harding J.E. 2009. Effects of sex, litter size and periconceptional ewe nutrition on the ewe-lamb bond. Applied Animal Behaviour Science. 120(1-2): 76-83.

Hernandez C.E., Matthews L.R., Oliver M.H., Bloomfield F.H. & Harding J.E. 2010. Effects of sex, litter size and periconceptional ewe nutrition on offspring behavioural and physiological response to isolation. Physiology & Behavior. 101(5): 588-594.

Jephcott E.H., McMillen I.C., Rushen J.P. & Thorburn G.D. 1987. A comparison of the effects of electroimmobilisation and, or, shearing procedures on ovine plasma concentrations of beta-endorphin/beta-lipoprotein and cortisol. Research in Veterinary Science. 43(1): 97-100.

Long N.M., Nathanielsz P.W. & Ford S.P. 2012. The impact of maternal overnutrition and obesity on hypothalamicpituitary-adrenal axis response of offspring to stress. Domestic Animal Endocrinology. 42(4): 195-202.

Mears G.J. & Brown F.A. 1997. Cortisol and β-endorphin responses to physical and psychological stressors in lambs. Canadian Journal of Animal Science. 77(4): 689-694.

Mears G.J., Brown F.A. & Redmond L.R. 1999. Effects of handling, shearing and previous exposure to shearing on cortisol and beta-endorphin responses in ewes. Canadian Journal of Animal Science. 79(1): 35-38.

Minton J.E., Coppinger T.R., Reddy P.G., Davis W.C. & Blecha F. 1992. Repeated restraint and isolation stress alters adrenal and lymphocyte functions and some leukocyte differentiation antigen in lambs. Journal of Animal Science. 70(4): 1126-1132.

Ramadoss J., Tress U., Chen W.J. & Cudd T.A. 2008. Maternal adrenocorticotropin, cortisol, and thyroid hormone responses to all three-trimester equivalent repeated binge alcohol exposure: ovine model. Alcohol. 42(3): 199-205.

Smith R.F. & Dobson H. 2002. Hormonal interactions within the hypothalamus and pituitary with respect to stress and reproduction in sheep. Domestic Animal Endocrinology. 23(1-2): 75-85.

Tallet C., Veissier I. & Boivin X. 2009. How does the method used to feed lambs to modulate their affinity to their human caregiver? Applied Animal Behaviour Science. 119(1-2): 56-65.

Turner A.I., Canny B.J., Hobbs R.J., Bond J.D., Clarke I.J. & Tilbrook A.J. 2002. Influence of sex and gonadal status of sheep on cortisol secretion in response to ACTH and on cortisol and LH secretion in response to stress: importance of different stressors. Journal of Endocrinology. 173(1): 113-22.

van Lier E., Pérez-Clariget R. & Forsberg M. 2003. Sex differences in cortisol secretion after administration of an ACTH analogue in sheep during the breeding and non-breeding season. Animal Reproduction Science. 79(1-2): 81-92.

Published

2016-01-01

How to Cite

Fazio, E., Medica, P., Cravana, C., & Ferlazzo, A. (2016). Pituitary-Adrenal Axis Responses to Routine Management Procedures in Sheep (Ovis aries). Acta Scientiae Veterinariae, 44(1), 7. https://doi.org/10.22456/1679-9216.81164

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Articles