Recently, the European Union published regulations regarding the welfare of horses during transport requiring that horses be transported in individual stalls separated by partitions. The objective of this study was to determine if concentrations of cortisol, corticosterone, or dehydroepiandrosterone (DHEA) differed among horses with no prior transport experience when transported in individual stalls versus loose groups. Twenty na�ve yearlings were assigned to either individual stalls or a loose group, then transported for 6 hours. Ten horses were transported per day (5 in stalls and 5 in a loose group) over a two day trial. The experiment was replicated with a second trial 35 days later, and utilized a switchback design where the horses exchanged treatments between trials. Blood samples were collected and analyzed for cortisol, corticosterone, and DHEA concentrations at pre-transport, 2, 4, and 6 h of transport, and at 2 and 4 h after unloading. After Trial 2, the horses? changed housing from group paddocks to stalls and a follow-up experiment was conducted. The data were analyzed using a mixed model repeated measures ANOVA with the animal as the subject, with trial, treatment, sample time, and treatment-sample time interaction in the model with unstructured covariance (SAS 9.1). Differences between sample times within each trial, and pre-transport concentrations between trials, were analyzed using paired t-tests (SPSS 12.0.1). No significant differences were found in hormone concentrations for horses transported in individual stalls versus in loose groups. Horses exhibited a significant elevation in cortisol and corticosterone during transport which returned to pre-transport concentrations by 2 hr after transport (P < 0.01). Mean pre-transport cortisol concentrations rose significantly in Trial 3 (7.87 ng/ml) from Trials 1 (2.71 ng/ml) and 2 (2.84 ng/ml) (P < 0.001). Pre-transport concentrations of DHEA in Trials 1 (482 pg/ml) and 2 (392 pg/ml) also rose significantly in Trial 3 (1607 pg/ml) (P < 0.01). Changes in cortisol and DHEA indicated that transportation was a significant stressor for horses, however, being transported in a loose group versus individual stalls was not different. Also, housing changes from paddocks to stalls resulted in significant increases in pre-transport concentrations of stress-related compounds.

In the stallion, inconsistent sexual behavior and variable semen quality are common. This reproductive variability has been attributed to differences in circulating hormone concentrations. In order to further examine this relationship, 7 miniature stallions were observed for sexual behavior and semen characteristics. Blood was also drawn from each stallion 15 min before mating (time -15), immediately following ejaculation (time 0) and at times following ejaculation (times +15, +30, and +60). Plasma was later analyzed for concentrations of testosterone (T), estrone sulphate (ES) and cortisol. Semen was evaluated for volume, sperm concentration and progressive motility. Sexual behavior was quantified by assigning a libido score to each stallion, recording reaction time and the number of jumps required for ejaculation. Upon statistical analysis, data revealed both ES and cortisol increased at the time of semen collection (P < 0.05), while T did not. Regression analysis revealed that ES and the ratio of ES to T at times -15, +30, and +60 were negatively correlated to libido scores. Additionally, a positive relationship was found between ES at times -15 and +60 and reaction time, as well as between cortisol at times -15, 0, and +15 and libido scores. No relationship was observed between T and sexual behavior. However, T at time -15 was positively correlated to progressive motility, and the ratio of ES/T at time -15 was negatively correlated to progressive motility. No other association was detected between ejaculate parameters and hormone concentrations. These results not only serve to enhance understanding of stallion hormone profiles, but also provide further insight into the hormonal control of sexual behavior and sperm production. This knowledge can be used to generate improved management techniques for stallions that are inconsistent in sexual behavior and sperm output.

The cumulative risk model is used to explain the coexistence of small gender differences and large health disparities between husbands and wives. Specifically, the current model incorporates conflict (a risk factor), support (a protective factor), and coping (a moderator of the conflict-stress link) to predict cortisol slopes for newlywed husbands and wives. One hundred and seventy-two couples completed both global and daily measures of protective factors (empathy, responsiveness, and perceived support), risk factors (withdrawal, loyalty, self-silencing, and negativity), and coping (self-distraction, substance use, emotional support, and rumination). For the six days that participants provided daily reports of these constructs, participants also provided waking and evening saliva samples for later determination of salivary cortisol levels. I hypothesized that men would incur more protective factors than would women, and that these protective factors would be associated with steeper cortisol slopes (i.e., healthy cortisol slopes.) Further, I hypothesized that women would incur more cumulative risks than would men, and that these risks would be associated flatter cortisol slopes (i.e., unhealthy cortisol slopes). Finally, I hypothesized that the association between cumulative risk and cortisol slopes would be moderated by coping, such that theoretically-effective coping strategies would blunt the impact of cumulative risks whereas ineffective coping strategies would exacerbate the impact of cumulative risks. Support for these hypotheses was mixed. Women did incur fewer cumulative protective factors than did men; however, there were no gender differences in cumulative risks for this highly satisfied newlywed sample. The impact of both cumulative protection and cumulative risk on cortisol slopes differed for men and women. Coping moderated the impact of cumulative risk on daily cortisol slopes, but again these patterns were different for men and women. Future work must continue to isolate gender differences in relationship processes to understand resulting health implications. With further refinement, the proposed model can provide a more holistic explanation of gendered health disparities, and perhaps identify ways that women and men can experience more equivalent health benefits from romantic relationships. / text

Οι ομάδες των ορμονών που επηρεάζουν σημαντικά την αύξηση και την ανάπτυξη των παιδιών και των εφήβων, ανήκουν κυρίως στον άξονα της αύξησης και της αναπαραγωγής, στο σύστημα του stress και στο ανοσολογικό σύστημα. Η κορτιλόλη, η λεπτίνη και η IL-6 αποτελούν στρεσογόνους παράγοντες οι οποίοι συνδέονται με τη δυναμική της ανάπτυξης και ενηβωσης του ανθρώπινου οργανισμού. Εκτός από την επίδραση τον ορμονών, η ενήβωση και η αναπαραγωγή του φύλου μπορεί να επηρεαστεί από φαρμακολογικούς παράγοντες, όπως είναι η υδροκορτιζόνη, τα αναβολικά στεροειδή και τα οιστρογόνα. Η φυσική άσκηση είναι ένας τύπος φυσικού stress που προκαλεί πλήθος ορμονικών, μεταβολικών και ανοσολογικών αλλαγών ενώ οι αθλητές και οι αθλήτριες ρυθμικής και ενόργανης γυμναστικής εκτίθονται σε έντονους φυσικούς και ψυχολογικούς στρεσογόνους παράγοντες. Τα τελευταία χρόνια οι προσδιορισμοί στο σίελο προσελκύουν τεράστιο ενδιαφέρον (λόγω του ανώδυνου τρόπου συλλογής του σιέλου) και κυρίως χρησιμοποιούνται στην Ενδοκρινολογία για την παρακολούθηση των επιπέδων των στεροειδών ορμονών. Υλικά και Μέθοδοι: Μελετήθηκαν 142 αθλήτριες και 97 αθηλτές της ενόργανης γυμναστικής υψηλού αγωνιστικού επιπέδου καθώς και 107 αθλήτριες της ρυθμικής γυμναστικής. Ως ομάδα ελέγχου μελετήθηκαν 73 κορίτσια και 68 αγόρια, τα οποία δεν αθλούνταν. Η συλλογή των δειγμάτων έγινε χρησιμοποιώντας μια ειδικά σχεδιασμένη συσκευή συλλογής σιέλου (Salivette). Για τον προσδιορισμό της λεπτίνης στο σίελο χρησιμοποιήθηκε ραδιοανοσολογική μέθοδος ενώ για τον προσδιορισμό της κορτιζόλης η μέθοδος ηλεκτροχημειοφωταύγειας. Για την μέτρηση της IL-6 στο σίελο αναπτύχθηκε και επικυρώθηκε μέθοδος Elisa υψηλής ευαισθησίας. Αποτελέσματα: Οι αθήτριες της ρυθμικής και της ενόργανης γυμναστικής χαρακτηρίζονται από υψηλότερα επίπεδα κορτιζόλης στο σίελο (p<0,01) συγκριτικά με τους μάρτυρες και τους αθλητές της ενόργανης. Τόσο στους αθλητές όσο και στις αθλήτριες της ενόργανης γυμναστικής, οι απογευματινές τιμές κορτιζόλης (μετά από άσκηση) παραμένουν στα ίδια επίπεδα με τις πρωινές τιμές. Στις αθλήτριες της ενόργανης τα επίπεδα της IL-6 παρουσιάζουν τάση αύξησης και της λεπτίνης τάση μείωσης μετά από άσκηση, αν και οι μεταβολές αυτές δεν είναι στατιστικά σημαντικές. Η συλλογή του σιέλου είναι μια μη επεμβατική, ανώδυνη τεχνική που επιτρέπει την επαναλαμβανόμενη δειγματοληψία. Η ραδιοανοσολογικής μέθοδος είναι απλή και εύκολη για τον προσδιορισμό της λεπτίνης στο σίελο, ενώ η μέθοδος της ηλεκτροχημειοφωταύγειας αποτελεί αξιόπιστη επιλογή για τη μέτρηση της κορτιζόλης στο σίελο. Για τον προσδιορισμό της IL-6 στο σίελο απαιτείται η ανάπτυξη και η επικύρωση μεθόδου Elisa, λόγω του ότι ο σίελος επηρεάζει τη μέτρηση της συγκεκριμένης κυτοκίνης. Τόσο στις αθλήτριες όσο και στους αθλητές της ενόργανης γυμναστικής υψηλού αγωνιστικού επιπέδου, ο νυχθημερήσιος ρυθμός έκκρισης της κορτιζόλης καταργείται. Επίσης οι αθλήτριες της ενόργανης γυμναστικής χαρακτηρίζονται από υψηλότερες τιμές δεικτών stress συγκριτικά με τους αθλητές. / The aim of this study was to evaluate the effects of intensive physical exercise and acute psychological stress during high level athletic competition as reflected on the levels of salivary cortisol, leptin and IL-6 in elite artistic and rytmic gymnasts. Design: The study included two hundred and forty-nine (249) Caucasian athletes (elite Gymnasts) -142 girls(aged 16.0 ± 1.6 years) and 97 boys (aged 16.8 ± 1.1 years) from 44 European countries, during theEuropean Championship of Gymnastics held in Volos-Greece on April 2006. One hundred and forty-one pubertal adolescents, who were recruited from public schools in Greece, not engaged in strenuous sports activities were used as controls (73 girls aged 16.0 ± 1.4 years and 68 boys aged 15.3 ±2.0 years). Methods: Saliva samples were collected, the morning before training and in the afternoon shortly after the competition. Cortisol concentrations were measured using a chemmiluminesce method. Leptin and IL-6 concentrations were measured using RIA and ELISA methods. Acute stress was assessed using a questionnaire designed for the study. Results: No difference was found between morning and afternoon salivary cortisol levels in both male and female AG. Female AG presented higher levels of morning salivary cortisol than female controls (p<0.05). Both male and female AG had higher degree of psychological stress in comparison with controls . Female AG had higher morning and afternoon salivary cortisol levels and higher degree of stress than males. Conclusions: In elite AG the diurnal rhythm of salivary cortisol has been abolished, probably due to the strenuous training and competition conditions. Female AG presented higher levels of morning salivary cortisol and psychological stress compared to both male AG and female controls. The long term consequences of these modifications of the HPA axis remain to be elucidated.

Recent research has suggested that boredom is a construct that can be distinguished from similar affective states including apathy, anhedonia, and depression, using self-reports. The current study investigated whether boredom and sadness (an analogue for depression) are distinct in terms of their physiological signatures. State boredom and sadness were induced in a group of healthy participants while their physiological parameters of heart rate (HR), skin conductance (SCL), and cortisol levels were monitored. Results indicated that the autonomic nervous system response for both states can be characterized by directional fractionation, with boredom resulting in increased HR but decreased SCL relative to sadness. Cortisol levels were higher after the boring induction than the sad induction, indicating increased hypothalamic-pituitary-adrenal axis activation for boredom. Overall, boredom appears to have a physiological signature that is distinguishable from a primary symptom of depression.

The purpose of this study was to characterize the endocrine stress response of zebrafish (Danio rerio) and to test if this response is modified by sex or the major sex steroids 17β-estradiol (E2) and 11-ketotestosterone (11KT). A standardized stress of having zebrafish swim in a beaker of stirring water resulted in rapid and transient changes in whole-body cortisol. While the cortisol response of males and females were comparable, exposure to E2 (100 ng/L) for 48 h inhibited the cortisol response of males and exposure to 11KT (100ng/L) for 48 h stimulated the cortisol response of females. The inhibitory actions of E2 were mediated in part by decreases in corticotropin releasing factor (crf) expression and decreases in the synthesis of cortisol by interrenal tissue. This research adds to the increasing knowledge of zebrafish physiology and will be useful for future studies concerning the endocrine stress response in fish.

This thesis investigates the use of an enzyme immunoassay to measure keratin glucocorticoid concentrations in mammalian hair, bird feathers and reptilian shed skins. Keratin glucocorticoid concentrations were compared to fecal glucocorticoid concentrations produced during the period of keratin growth in the African Elephant (Loxodonta africana), the Western Lowland Gorilla (Gorilla gorilla gorilla), the Sumatran Orangutan (Pongo abelii), the Domestic Chicken (Gallus gallus domesticus), the Eastern Loggerhead Shrike (Lanius ludovicianus migrans), the African House Snake (Lamprophis fuliginosus) and the Eastern Massasauga Rattlesnake (Sistrurus catenatus catenatus). Complete biochemical validation was performed for the feather and shed skin corticosterone and fecal corticosterone enzyme immunoassays in the Domestic Chicken and the African House Snake. Biological validation was performed in the Domestic Chicken. Biological and physiological validation were attempted in the African House Snake. African Elephant, Western Lowland Gorilla and Sumatran Orangutan hair cortisol concentrations ranged from 2.10 - 312.70 ng/g. African Elephant hair corticosterone concentrations ranged from 2.68 - 20.70 ng/g. Domestic Chicken and Eastern Loggerhead Shrike feather corticosterone concentrations ranged from 1.31 - 8.09 pg/mm and from 1.09 - 6.59 pg/mm, respectively. African House Snake and Massasauga Rattlesnake shed skin corticosterone concentrations ranged from 4.42 - 124.35 ng/g and 3.82 - 22.85 ng/g, respectively. In the majority of cases, a statistically significant association was not found between summary statistical measures of fecal and keratin glucocorticoid concentrations. A statistically significant positive association was detected between hair cortisol and the coefficient of variation of fecal corticosterone in the African Elephants. A statistically significant negative association was detected between feather corticosterone and the 75th percentile and coefficient of variation of fecal corticosterone in the Eastern Loggerhead Shrikes. A statistically significant positive association was also detected between shed skin corticosterone and the mean fecal corticosterone from 3 weeks before to 1 week after the previous ecdysis in the African House Snake. Feather corticosterone concentrations were significantly higher in feathers from Domestic Chickens that were socially housed with roosters than in feathers from chickens housed individually in laying cages. A statistically significant difference was not detected between the shed skin corticosterone concentrations of the minimally handled control and the weekly handled experimental African House Snakes. Adrenocorticotropic hormone stimulation did not result in the physiological validation anticipated for shed skin corticosterone concentrations in the African House Snake. / Toronto Zoological Foundation and Ontario Ministry of Agriculture, Food and Rural Affairs

A number of routine painful procedures such as castration and tail-docking are currently performed in swine production without the benefit of anaesthesia or analgesia. In addition, parturition is generally considered painful. Providing analgesics at the time of castration and tail-docking lowered plasma cortisol levels of the piglets suggesting a reduction in pain associated with the procedures. The use of the non-steroidal antiinflammatory drug meloxicam also resulted in less isolated behaviour of male piglets following castration. Providing meloxicam routinely following parturition did not result in reduced neonatal mortality or piglet growth, but lowered plasma cortisol suggesting a reduction in pain. Producers in the future may need to consider using pain control as part of their standard operating procedures in order improve piglet welfare and meet their consumers’ expectations, but are unlikely to see an economic return associated with improved productivity. / Please do not reject this before tomorrow afternoon. I am going to stop by the Office of Graduate Studies and hand in the necessary documents. / Boehringer Ingelheim (Canada) Ltd. and Ontario Pork

Few studies have compared cortisol responses to psychological and physical stress tasks with or without social evaluation. Flow-mediated dilation (FMD) with reactive hyperemia is impaired following acute stress though less is known regarding the impact of stress and cortisol on FMD with exercise induced increases in shear stress (EX-FMD). The purpose of this study was 1) to compare cortisol responses between the Trier Social Stress Test (TSST) and 5min cold pressor test with and without social evaluation (CPT, CPT+SE) and 2) to examine the impact of these stressors and cortisol elevation on EX-FMD. 59 healthy male subjects were randomly assigned to one of three conditions: TSST, CPT, or CPT+SE. Brachial artery EX-FMD was assessed before, 15 and 35min post-stress with Echo and Doppler ultrasound. Results are mean ± SD. Baseline parameters did not differ between conditions (p>.05) and stress responses were similar between the three conditions for peak cortisol: TSST 11.34±5.53nmol/L; CPT 10.08±4.48nmol/L; CPT+SE 8.51±3.60nmol/L; condition effect p=.292; cortisol responders only (increase >2nmol/L) TSST 12.48±5.24nmol/L; CPT 12.13±5.31nmol/L; CPT+SE 10.70±2.86nmol/L; condition effect p=.560; peak MAP: 131.99 ±18.56mmHg, condition effect p=.664; peak TPR: 25.84 ± 9.78mmHg/L/min, condition effect p=0.841; peak stress rating out of 10: 5.11 ± 2.12, condition effect p= 0.292; with the exception of HR (TSST: 95.06 ± 15.29bpm; CPT: 79.00 ± 11.85bpm; CPT+SE: 77.98 ± 7.66bpm; condition effect p= 0.003) and pain ratings out of 10 (TSST: 1.21 ± 1.72; CPT: 6.66 ± 1.42; CPT+SE: 6.38 ± 1.73; condition effect p<.001). Shear stress was lower in the 15min post-stress vs. pre stress and 35min post-stress trials (72.34 ± 4.46; 15min post-stress: 70.79 ± 5.39; 35min post-stress: 70.60 ± 6.10; condition effect p= 0.592; trial effect: p= 0.018). EX-FMD increased from pre- stress to 15min post-stress in all conditions (pre-stress 6.22 ± 2.75%; 15min-post stress: 7.91 ± 3.24%; 35min post-stress: 6.60 ± 2.93%; trial effect p<.001). No correlation between change in EX-FMD and change in cortisol was detected (r2= 0.0125; p=.404). In conclusion, the TSST, CPT and CPT+SE elicited similar stress responses and stress transiently enhanced EX-FMD. Cortisol responses did not explain the enhanced EX-FMD post stress. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2012-09-14 15:41:33.325

Caffeine, one of the most commonly consumed substances worldwide, acts as a biogenic stressor and elicits both cardiovascular and endocrine stress responses. The most commonly described endocrine stress response is the hypothalamic-pituitary-adrenal (HPA) axis, whose final product is cortisol. Cortisol is well described as an indicator of stress levels, and it may be elevated chronically in persistently stressful situations. Its subsequent effects include blood pressure elevation, which is an indicator of cardiovascular stress reactivity. Research shows that cardiovascular and endocrine stress responses attenuate—albeit incompletely—with habitual caffeine consumption. However, when caffeine consumption and situational stressors are combined, stress reactivity is potentiated, raising concerns about long-term effects in populations who are regularly exposed to both. Numerous sex-related factors complicate this area of research in female cohorts. Endocrine considerations, especially relating to fluctuating estradiol levels, are well known to affect both caffeine metabolism and stress reactivity. Prior studies, ranging from biochemical to epidemiological levels, have identified variability in caffeine metabolism and stress reactivity attributable to menstrual cycle phase and recent pregnancy. Cardiovascular stress reactivity patterns differ, furthermore, between males and females, a reality that translates to differences in cardiovascular disease risk and forms a critical area of future research with broad public health implications. Based on extensive review of caffeine metabolism and stress reactivity literature, focusing on studies relevant to young females with varying habitual levels of caffeine consumption, I designed a study proposal to further characterize these physiological stress responses within this demographic. The core goal of the proposed study is to assess changes in plasma free cortisol concentration and blood pressure following an acute dose of caffeine (200 mg) at peak (40 min) and elimination half-life (160 min) caffeine plasma concentration time points. Average daily caffeine consumption (low, medium, or high) and menstrual cycle phase were included as additional parameters of interest in order to further characterize interactions within the selected demographic.