Reduced Cortisol and Metabolic Responses of Thin Ewes to an Acute Cold Challenge in Mid-Pregnancy: Implications for Animal Physiology and Welfare

Verbeek, Else; Oliver, Mark Hope; Waas, Joseph R.; McLeay, Lance M.; Blache, Dominique; Matthews, Lindsay R.

Reduced Cortisol and Metabolic Responses of Thin Ewes to an Acute Cold Challenge in Mid-Pregnancy: Implications for Animal Physiology and Welfare

dc.contributor.author	Verbeek, Else
dc.contributor.author	Oliver, Mark Hope
dc.contributor.author	Waas, Joseph R.
dc.contributor.author	McLeay, Lance M.
dc.contributor.author	Blache, Dominique
dc.contributor.author	Matthews, Lindsay R.
dc.coverage.spatial	United States	en_NZ
dc.date.accessioned	2012-07-24T00:15:02Z
dc.date.available	2012-07-24T00:15:02Z
dc.date.copyright	2012-05-25
dc.date.issued	2012
dc.description.abstract	Background: Low food availability leading to reductions in Body Condition Score (BCS; 0 indicates emaciation and 5 obesity) in sheep often coincides with low temperatures associated with the onset of winter in New Zealand. The ability to adapt to reductions in environmental temperature may be impaired in animals with low BCS, in particular during pregnancy when metabolic demand is higher. Here we assess whether BCS affects a pregnant animal’s ability to cope with cold challenges. Methods: Eighteen pregnant ewes with a BCS of 2.760.1 were fed to attain low (LBC: BCS2.360.1), medium (MBC: BCS3.260.2) or high BCS (HBC: BCS3.660.2). Shorn ewes were exposed to a 6-h acute cold challenge in a climate-controlled room (wet and windy conditions, 4.460.1uC) in mid-pregnancy. Blood samples were collected during the BCS change phase, acute cold challenge and recovery phase. Results: During the BCS change phase, plasma glucose and leptin concentrations declined while free fatty acids (FFA) increased in LBC compared to MBC (P,0.01, P,0.01 and P,0.05, respectively) and HBC ewes (P,0.05, P,0.01 and P,0.01, respectively). During the cold challenge, plasma cortisol concentrations were lower in LBC than MBC (P,0.05) and HBC ewes (P,0.05), and FFA and insulin concentrations were lower in LBC than HBC ewes (P,0.05 and P,0.001, respectively). Leptin concentrations declined in MBC and HBC ewes while remaining unchanged in LBC ewes (P,0.01). Glucose concentrations and internal body temperature (Tcore) increased in all treatments, although peak Tcore tended to be higher in HBC ewes (P,0.1). During the recovery phase, T4 concentrations were lower in LBC ewes (P,0.05). Conclusion: Even though all ewes were able to increase Tcore and mobilize glucose, low BCS animals had considerably reduced cortisol and metabolic responses to a cold challenge in mid-pregnancy, suggesting that their ability to adapt to cold challenges through some of the expected pathways was reduced.	en_NZ
dc.format.mimetype	application/pdf
dc.identifier.citation	Verbeek, E., Oliver, M.H., Waas, J.R., McLeay, L.M., Blache, D. & Matthews, L.R. (2012). Reduced cortisol and metabolic responses of thin ewes to an acute cold challenge in mid-pregnancy: Implications for animal physiology and welfare. PLoS ONE, 7(5), e37315.	en_NZ
dc.identifier.doi	10.1371/journal.pone.0037315.t002	en_NZ
dc.identifier.uri	https://hdl.handle.net/10289/6555
dc.language.iso	en
dc.publisher	Plos One	en_NZ
dc.relation.isPartOf	Plos One	en_NZ
dc.relation.ispartof	PLoS ONE
dc.relation.uri	http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0037315	en_NZ
dc.rights	© 2012 Verbeek et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.	en_NZ
dc.subject	biology	en_NZ
dc.title	Reduced Cortisol and Metabolic Responses of Thin Ewes to an Acute Cold Challenge in Mid-Pregnancy: Implications for Animal Physiology and Welfare	en_NZ
dc.type	Journal Article	en_NZ
pubs.begin-page	1	en_NZ
pubs.elements-id	37703
pubs.end-page	15	en_NZ
pubs.issue	5	en_NZ
pubs.volume	7	en_NZ