|   | 
Details
   web
Records
Author Franceschini, C.; Siutz, C.; Palme, R.; Millesi, E.
Title Seasonal changes in cortisol and progesterone secretion in Common hamsters Type Journal Article
Year (up) 2007 Publication General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol
Volume 152 Issue 1 Pages 14-21
Keywords Animals; Cortisone/*secretion; Cricetinae/*metabolism; Feces/chemistry; Female; Lactation/physiology; Male; Pregnancy; Progesterone/*secretion; Reproduction/physiology; *Seasons; Sexual Behavior, Animal/physiology
Abstract In this study, we investigated endocrine factors and behaviour in free-living Common hamsters (Cricetus cricetus) during reproductive and non-reproductive periods of the annual cycle. We applied a non-invasive method to gain information on seasonal changes in adrenocortical activity in male and female hamsters by analysing faecal glucocorticoid metabolite concentrations (FCM). In addition, plasma progesterone concentrations were monitored in females throughout the non-hibernation season. The animals were live-trapped from spring emergence until the onset of hibernation in autumn. Reproductive status was determined at capture and blood and faecal samples were collected. During behavioural observations, agonistic and sexual interactions were recorded. FCM concentrations were significantly higher in males than in females during the reproductive period. In males, a pronounced increase in FCM during the reproductive period coincided with high frequencies of intrasexual aggression. In females, FCM levels remained relatively constant. Aggressive behaviour in females increased during the reproductive period, but was much less frequent than in males. Females, which successfully raised a second litter after a postpartum oestrus and concurrent lactation and gestation had lower FCM levels than individuals, which lost their second litter after parturition. As expected, plasma progesterone concentrations were low before and after the reproductive period. During gestation, levels peaked and remained elevated during lactation. The results of this field study provide insight in critical periods associated with reproduction in male and female Common hamsters.
Address Department of Behavioural Biology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria. claudia.franceschini@univie.ac.ct
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0016-6480 ISBN Medium
Area Expedition Conference
Notes PMID:17408667 Approved no
Call Number Equine Behaviour @ team @ Serial 4076
Permanent link to this record
 

 
Author Wolf, M.; van Doorn, G.S.; Leimar, O.; Weissing, F.J.
Title Life-history trade-offs favour the evolution of animal personalities Type Journal Article
Year (up) 2007 Publication Nature Abbreviated Journal Nature
Volume 447 Issue 7144 Pages 581-584
Keywords Aggression/physiology/psychology; Animals; Behavior, Animal/*physiology; *Evolution; Exploratory Behavior/physiology; Models, Biological; Personality/*physiology; Predatory Behavior/physiology; Reproduction/physiology; Risk-Taking; Selection (Genetics)
Abstract In recent years evidence has been accumulating that personalities are not only found in humans but also in a wide range of other animal species. Individuals differ consistently in their behavioural tendencies and the behaviour in one context is correlated with the behaviour in multiple other contexts. From an adaptive perspective, the evolution of animal personalities is still a mystery, because a more flexible structure of behaviour should provide a selective advantage. Accordingly, many researchers view personalities as resulting from constraints imposed by the architecture of behaviour (but see ref. 12). In contrast, we show here that animal personalities can be given an adaptive explanation. Our argument is based on the insight that the trade-off between current and future reproduction often results in polymorphic populations in which some individuals put more emphasis on future fitness returns than others. Life-history theory predicts that such differences in fitness expectations should result in systematic differences in risk-taking behaviour. Individuals with high future expectations (who have much to lose) should be more risk-averse than individuals with low expectations. This applies to all kinds of risky situations, so individuals should consistently differ in their behaviour. By means of an evolutionary model we demonstrate that this basic principle results in the evolution of animal personalities. It simultaneously explains the coexistence of behavioural types, the consistency of behaviour through time and the structure of behavioural correlations across contexts. Moreover, it explains the common finding that explorative behaviour and risk-related traits like boldness and aggressiveness are common characteristics of animal personalities.
Address Theoretical Biology Group, Centre for Ecological and Evolutionary Studies, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1476-4687 ISBN Medium
Area Expedition Conference
Notes PMID:17538618 Approved no
Call Number Equine Behaviour @ team @ Serial 4098
Permanent link to this record
 

 
Author Bell, A.M.
Title Evolutionary biology: animal personalities Type
Year (up) 2007 Publication Nature Abbreviated Journal Nature
Volume 447 Issue 7144 Pages 539-540
Keywords Aggression/physiology/psychology; Animals; Behavior, Animal/*physiology; *Evolution; Humans; *Models, Biological; Personality/genetics/*physiology; Reproduction/genetics/physiology; Risk-Taking; Selection (Genetics)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1476-4687 ISBN Medium
Area Expedition Conference
Notes PMID:17538607 Approved no
Call Number Equine Behaviour @ team @ Serial 4099
Permanent link to this record
 

 
Author Kampmann, S.; Hampson, B.A.; Pollitt, C.C.
Title Population dynamics of feral horses (Equus caballus) following above-average rainfall in a semi-arid environment of Australia Type Journal Article
Year (up) 2013 Publication Australian Veterinary Journal Abbreviated Journal Aust Vet J
Volume 91 Issue 11 Pages 482-487
Keywords animal welfare; ecology; horses; reproduction; wildlife
Abstract Background Recent record rainfall in much of semi-arid Central Australia is the most likely reason for a feral horse population increase in excess of normal. Uncontrolled numbers of feral horses have habitat degradation and animal welfare implications. Objectives The aims of this study were to investigate the social structure of feral horses and assess their population growth rate following unseasonably high rainfall. Methods The study area was 4000 km2 of unmanaged, semi-arid country in Central Australia (latitude 24.50°S, longitude 132.10°E). Horses were identified by descriptive features from ground searches, movement-activated cameras and ‘hides’ positioned at key water holes. Wherever possible, sex and age categories were documented. Population growth rate was estimated by the number of foals divided by the number of horses older than 1 year in the observed population. Results A total of 1424 horses were identified and categorised, of which 335 were foals born within the current year. Only 123 juveniles were identified. Of the adult horses, 53.4% were male and 46.6% were female and this differed from parity (P = 0.04). Of the mares, 71.9% had a foal at foot and the population growth rate was 29.5%. Conclusions With a sustained population growth rate of 29.5%, this population of feral horses will more than double within 3 years. The high population increase will likely have a detrimental effect on native fauna and flora and the fragile, semi-arid ecosystems of Central Australia. After a period of high rainfall and plentiful resources, ‘normal’ drought conditions will return and many feral horses will starve and die as they compete for limited resources.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1751-0813 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5747
Permanent link to this record
 

 
Author Palme, R.; Touma, C.; Arias, N., Dominchin, M.N.; Lepschy, M.
Title Steroid extraction: Get the best out of faecal samples Type Journal Article
Year (up) 2013 Publication Wiener Tierärztliche Wochenschriften Abbreviated Journal Wien Tierärztl Monat – Vet Med Austria
Volume 100 Issue Pages 238-246.
Keywords Review, faeces, extraction, non-invasive hormone monitoring, stress, reproduction.
Abstract Faecal steroid hormone metabolites are becoming increasingly popular as parameters for reproductive functions and stress. The extraction of the steroids from the faecal matrix represents the initial step before quantification can be performed. The steroid metabolites present in the faecal matrix are of varying polarity and composition, so selection of a proper extraction procedure is essential. There have been some studies to address this complex but often neglected point. Radiolabelled steroids (e.g. cortisol or progesterone) have frequently been added to faecal samples to estimate the efficiency of the extraction procedures used. However, native, unmetabolized steroids are normally not present in the faeces and therefore the results are artifi- cial and do not accurately reflect the actual recoveries of the substances of interest. In this respect, recovery experiments based on faecal samples from radiometabolism studies are more informative. In these samples, the metabolite content accurately reflects the mixture of metabolites present in the given species. As a result, it is possible to evaluate different extraction methods for use with faecal samples. We present studies on sheep, horses, pigs, hares and dogs that utilized samples containing naturally metabolized, 14C-labelled steroids. We recommend extracting faecal steroids by simply suspending the faeces in a high percentage of a primary alcohol (for glucocorticoid metabolites 80% aqueous methanol proved best suited for virtually all mammalian species tested so far). Not only does the procedure significantly increase the total amount of recovered radioactivity, it also increases the percentage of unconjugated metabolites, which are more likely to be recognized by the antibodies used in various immunoassays. The advantages of this extraction procedure are clear: it is very easy to use (no evaporation step is needed), it yields high recoveries and variation based on the extraction procedure is reduced to a minimum.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 6520
Permanent link to this record
 

 
Author Aurich, J.; Wulf, M.; Ille, N.; Erber, R.; von Lewinski, M.; Palme, R.; Aurich, C.
Title Effects of season, age, sex and housing on salivary cortisol concentrations in horses Type Journal Article
Year (up) 2015 Publication Domestic Animal Endocrinology Abbreviated Journal Domest. Anim. Endocrinol.
Volume Issue Pages
Keywords horse; cortisol; diurnal rhythm; reproduction; housing
Abstract Abstract Analysis of salivary cortisol is increasingly used to assess stress responses in horses. Since spontaneous or experimentally induced increases in cortisol concentrations are often relatively small for stress studies proper controls are needed. This requires an understanding of factors affecting salivary cortisol over longer times. In this study, we have analysed salivary cortisol concentration over 6 mo in horses (n = 94) differing in age, sex, reproductive state and housing. Salivary cortisol followed a diurnal rhythm with highest concentrations in the morning and a decrease throughout the day (P < 0.001). This rhythm was disrupted in individual groups on individual days; however, alterations remained within the range of diurnal changes. Comparison between months showed highest cortisol concentrations in December (P < 0.001). Cortisol concentrations increased in breeding stallions during the breeding season (P < 0.001). No differences in salivary cortisol concentrations between non-pregnant mares with and without a corpus luteum existed. In stallions, mean daily salivary cortisol and plasma testosterone concentration were weakly correlated (r = 0.251, P < 0.01). No differences in salivary cortisol between female and male young horses and no consistent differences between horses of different age existed. Group housing and individual stabling did not affect salivary cortisol. In conclusion, salivary cortisol concentrations in horses follow a diurnal rhythm and are increased in active breeding sires. Time of the day and reproductive state of the horses are thus important for experiments that include analysis of cortisol in saliva.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0739-7240 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5847
Permanent link to this record