1
|
Viblanc VA, Pardonnet S, Tamian A, McCaw LK, Dobson FS, Boonstra R. Down-regulating the stress axis: Living in the present while preparing for the future. Gen Comp Endocrinol 2024; 354:114541. [PMID: 38685390 DOI: 10.1016/j.ygcen.2024.114541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 04/24/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
The measurement of glucocorticoid (GC) hormones provides us with a window into the stress physiology of vertebrates and the adaptative responses they use to cope with predictable and unpredictable changes in the environment. Baseline GCs inform us about the metabolic demands they are subject to at that point in their yearly life-history stage, whereas GC changes (often increases) in response to acute challenges inform us on their capacity to cope with more immediate environmental challenges. However, baseline GC levels and the kinetics of GC responses to acute stressors can vary substantially among and within species, depending on individual characteristics (age, sex, condition, life-history stage). In addition, a thorough understanding of the stress status of an animal requires moving beyond the measurement of GCs alone by focusing on downstream measures of metabolic activation, such as oxidative stress. Here, we evaluated the changes in blood cortisol and oxidative stress markers in wild adult Columbian ground squirrels (Urocitellus columbianus), following a 30-min capture-handling stress performed in mid-late June. Measurements were taken when males were post-reproductive and preparing for hibernation and adult females were weaning litters. We found three key results. First, the time-course of GC increase was markedly slower (by an order of magnitude) than what is currently reported in the literature for most species of mammals, birds and reptiles. Second, there were marked differences in the male and female response, linked to differences in life-history stage: females close to weaning had abolished GC responses, whereas post-reproductive males did not. Third, there were mild to moderate increases in oxidative damage and decreases in oxidative defenses in response to our short-term challenge, consistent with the idea that short-term acute metabolic activation may carry physiological costs. However, these changes were not correlated to the changes in GCs, a novel result suggesting a disconnect between the hormonal stress response and oxidative damage.
Collapse
Affiliation(s)
- Vincent A Viblanc
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France.
| | - Sylvia Pardonnet
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Anouch Tamian
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Laura K McCaw
- Department of Biological Sciences, Centre for the Neurobiology of Stress, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada
| | - F Stephen Dobson
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France; Department of Biological Sciences, Auburn University, Auburn, AL, USA
| | - Rudy Boonstra
- Department of Biological Sciences, Centre for the Neurobiology of Stress, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada
| |
Collapse
|
2
|
Tamian A, Edwards PD, Neuhaus P, Boonstra R, Ruckstuhl AN, Emmanuel P, Pardonnet S, Palme R, Filippi D, Dobson FS, Saraux C, Viblanc VA. Weathering the storm: Decreased activity and glucocorticoid levels in response to inclement weather in breeding Columbian ground squirrels. Horm Behav 2023; 155:105426. [PMID: 37716083 DOI: 10.1016/j.yhbeh.2023.105426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/22/2023] [Accepted: 08/31/2023] [Indexed: 09/18/2023]
Abstract
Inclement weather can rapidly modify the thermal conditions experienced by animals, inducing changes in their behavior, body condition, and stress physiology, and affecting their survival and breeding success. For animals living in variable environments, the extent to which they have adapted to cope with inclement weather is not established, especially for hibernating species with a short active season that are constrained temporally to breed and store energy for subsequent hibernation. We examined behavioral (foraging activity) and physiological (body mass and fecal cortisol metabolites) responses of Columbian ground squirrels (Urocitellus columbianus), small hibernating rodents inhabiting open meadows in Rocky Mountains, to 3 events of inclement weather (two snow storms in May 2021 and May 2022, one heavy rainfall in June 2022). We found that individuals adapted to inclement weather conditions by (1) reducing above-ground activity, including foraging, (2) decreasing the mobilization of stored resources as indicated by a decrease in the activity of the hypothalamo-pituitary-adrenal (HPA) axis and lower fecal cortisol metabolites in the hours/days following periods of inclement weather; and (3) compensating through increased foraging and more local activity when favorable conditions resumed. As a result, body mass and growth did not decrease following short periods of inclement weather. Columbian ground squirrels were well-adapted to short periods of inclement weather, coping via modifications of their behavior and the activity of the HPA axis.
Collapse
Affiliation(s)
- Anouch Tamian
- Institut Pluridisciplinaire Hubert Curien, CNRS, Département Ecologie, Physiologie et Ethologie, 23 Rue du Loess, 67037 Strasbourg, France.
| | - Phoebe D Edwards
- Department of Biological Sciences, University of Toronto Scarborough, ON M1C 1A4, Canada
| | - Peter Neuhaus
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Rudy Boonstra
- Department of Biological Sciences, University of Toronto Scarborough, ON M1C 1A4, Canada
| | | | - Patience Emmanuel
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Sylvia Pardonnet
- Institut Pluridisciplinaire Hubert Curien, CNRS, Département Ecologie, Physiologie et Ethologie, 23 Rue du Loess, 67037 Strasbourg, France
| | - Rupert Palme
- Department of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Dominique Filippi
- Sextant Technology Ltd., 131 Tutaenui Rd, RD2, 4788 Marton, New Zealand
| | - F Stephen Dobson
- Institut Pluridisciplinaire Hubert Curien, CNRS, Département Ecologie, Physiologie et Ethologie, 23 Rue du Loess, 67037 Strasbourg, France; Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Claire Saraux
- Institut Pluridisciplinaire Hubert Curien, CNRS, Département Ecologie, Physiologie et Ethologie, 23 Rue du Loess, 67037 Strasbourg, France
| | - Vincent A Viblanc
- Institut Pluridisciplinaire Hubert Curien, CNRS, Département Ecologie, Physiologie et Ethologie, 23 Rue du Loess, 67037 Strasbourg, France
| |
Collapse
|
3
|
Roth JD, Dobson FS, Neuhaus P, Abebe A, Barra T, Boonstra R, Edwards PD, Gonzalez MA, Hammer TL, Harscouet E, McCaw LK, Mann M, Palme R, Tissier M, Uhlrich P, Saraux C, Viblanc VA. Territorial scent-marking effects on vigilance behavior, space use, and stress in female Columbian ground squirrels. Horm Behav 2022; 139:105111. [PMID: 35063725 DOI: 10.1016/j.yhbeh.2022.105111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 12/26/2021] [Accepted: 01/04/2022] [Indexed: 11/16/2022]
Abstract
Social environments can profoundly affect the behavior and stress physiology of group-living animals. In many territorial species, territory owners advertise territorial boundaries to conspecifics by scent marking. Several studies have investigated the information that scent marks convey about donors' characteristics (e.g., dominance, age, sex, reproductive status), but less is known about whether scents affect the behavior and stress of recipients. We experimentally tested the hypothesis that scent marking may be a potent source of social stress in territorial species. We tested this hypothesis for Columbian ground squirrels (Urocitellus columbianus) during lactation, when territorial females defend individual nest-burrows against conspecifics. We exposed lactating females, on their territory, to the scent of other lactating females. Scents were either from unfamiliar females, kin relatives (a mother, daughter, or sister), or their own scent (control condition). We expected females to react strongly to novel scents from other females on their territory, displaying increased vigilance, and higher cortisol levels, indicative of behavioral and physiological stress. We further expected females to be more sensitive to unfamiliar female scents than to kin scents, given the matrilineal social structure of this species and known fitness benefits of co-breeding in female kin groups. Females were highly sensitive to intruder (both unfamiliar and kin) scents, but not to their own scent. Surprisingly, females reacted more strongly to the scent of close kin than to the scent of unfamiliar females. Vigilance behavior increased sharply in the presence of scents; this increase was more marked for kin than unfamiliar female scents, and was mirrored by a marked 131% increase in free plasma cortisol levels in the presence of kin (but not unfamiliar female) scents. Among kin scents, lactating females were more vigilant to the scent of sisters of equal age, but showed a marked 318% increase in plasma free cortisol levels in response to the scent of older and more dominant mothers. These results suggest that scent marks convey detailed information on the identity of intruders, directly affecting the stress axis of territory holders.
Collapse
Affiliation(s)
- Jeffrey D Roth
- Department of Biological Sciences, Auburn University, Auburn, AL, USA
| | - F Stephen Dobson
- Department of Biological Sciences, Auburn University, Auburn, AL, USA; Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France; University of Strasbourg, Institute of Advanced Sciences (USIAS), 5 allée du Général Rouvillois, 67083 Strasbourg, France
| | - Peter Neuhaus
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Asheber Abebe
- Department of Mathematics and Statistics, Auburn University, Auburn, AL, USA
| | - Thibaut Barra
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Rudy Boonstra
- Department of Biological Sciences, University of Toronto Scarborough, ON M1C 1A4, Canada
| | - Phoebe D Edwards
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Manuel A Gonzalez
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Tracey L Hammer
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France; Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Erwan Harscouet
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Laura K McCaw
- Department of Biological Sciences, University of Toronto Scarborough, ON M1C 1A4, Canada
| | - Maria Mann
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Rupert Palme
- Department of Biological Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Mathilde Tissier
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Pierre Uhlrich
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Claire Saraux
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
| | - Vincent A Viblanc
- Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France.
| |
Collapse
|
4
|
Larm M, Hovland AL, Palme R, Thierry AM, Miller AL, Landa A, Angerbjörn A, Eide NE. Fecal glucocorticoid metabolites as an indicator of adrenocortical activity in Arctic foxes (Vulpes lagopus) and recommendations for future studies. Polar Biol 2021. [DOI: 10.1007/s00300-021-02917-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AbstractMeasuring fecal glucocorticoid metabolites (fGCMs) is a widely used, non-invasive method for studies of stress in vertebrates. To study physiological responses in wild Arctic foxes (Vulpes lagopus) to perceived stressors such as fluctuating food availability, occurrence of competitors and predators and disturbance from human activities, a species-specific physiological validation of a method to evaluate adrenocortical activity is needed. Here we used 15 captive Arctic foxes (both males and females and juveniles and adults) to investigate fGCM concentrations following ACTH injection (physiological validation), or handling alone and compared them with their respective baseline concentrations prior to the treatments. A 5α-pregnane-3ß,11ß,21-triol-20-one enzyme immunoassay measured significant fGCM increases following both treatments. The time lags to reach peak fGCM values were 9.3 ± 1.3 h and 12.8 ± 1.7 h for ACTH and handling treatment, respectively. Concentrations of fGCMs varied a lot between individuals, but not attributed to sex nor age of the foxes. However, we found a negative relationship between boldness and fGCM concentrations. Faecal glucocorticoid metabolites concentrations did not change significantly over a period of 48 h in samples kept at temperatures reflecting winter and summer means. This would allow the collection of samples up to two days old in the wild regardless of the season. We conclude that our successfully validated method for measuring fGCMs can be used as a non-invasive tool for studies exploring various stressors both in wild and captive Arctic foxes.
Collapse
|