Despite the controversy over environmental sustainability, salmon aquaculture in British Columbia is economically important for many coastal communities and is reported as being the largest agricultural export product for the province. This thesis examined the welfare status of commercially produced Atlantic salmon smolts during transport from freshwater farms to the saltwater net pens using physiology and behaviour to assess transport stress. Smolts were transported first by truck from the freshwater farm to the dock, and then in the flow-through cargo holds of a live-haul vessel to the saltwater net pens. Fish and water were sampled before and after truck transport, and several times aboard the vessel. Assessment of stress was based on measurement of plasma cortisol, glucose, lactate, potassium, sodium and chloride concentrations, as well as behavioural observations made on underwater video footage. Seven transports of fish originating from two different hatcheries were sampled; one was a land-based tank hatchery that required a 30-min drive to the dock, and the other a lake net pen facility that was 90 min to the dock. Analysis of plasma constituents supported previous studies that recovery from the stress accumulated during loading and truck transport can be quite rapid in a live-haul vessel. Underwater video footage, recorded at the freshwater farms and in the cargo holds of the Sterling Carrier, also suggested recovery onboard in that for the most part, behaviour onboard was similar to behaviour at the freshwater farms. There were some significant differences between fish from the two types of hatcheries, particularly in the original hatchery conditions and in their behavioural responses to transport conditions; however, post-transport growth and mortality rates reported by the saltwater farms showed no significant difference. Although fish were subjected to moderately stressful conditions during part of the process, smolt transport as currently carried out by our industry partners reflects good husbandry practices and fish welfare. / Land and Food Systems, Faculty of / Graduate

Mountain caribou (Rangifer tarandus caribou) are endangered in British Columbia and motorized backcountry recreation has been identified as a potential threat to their persistence. My objective was to test if fecal glucocorticoids (GCs), indicative of physiological effects of ecological stress in wildlife, could be used as a non-invasive tool to quantify stress response in free-ranging caribou exposed to motorized recreation. I validated an enzyme-linked immunosorbent assay (ELISA) to measure concentration of fecal GCs for R. tarandus using an adrenocorticotropic hormone (ACTH) challenge experiment on captive reindeer exposed to extreme variation in winter weather. Female reindeer expressed elevated fecal GCs 9-11 hrs after ACTH injection. Males showed no detectable increase, perhaps due to underdosing. Fecal GCs varied markedly in both sexes in response to natural variation in weather. Overall, my results indicated fecal assays can be used to track biologically meaningful changes in adrenal activity in R.tarandus. I investigated the effects of motorized recreation on stress hormone production by measuring GCs in feces of mountain caribou exposed to snowmobile and heli-ski activity. Concentrations of fecal GCs in snowmobile and heli-ski areas were higher than those measured from caribou in areas where motorized recreation was not allowed. Caribou sampled up to 4km. 8km and I0 km distant from snowmobile activity showed elevated fecal GCs when compared to those sampled further from snowmobile activity areas. Other variables with a significant effect on fecal GCs included reproductive state, snow, aspect. minimum ambient temperature, and daily temperature range. My study indicates that measurement of fecal GCs provides a useful, noninvasive approach in the evaluation of physiological effects of environment, reproductive state, and human-induced stressors on free-ranging mountain caribou. Although research on many species indicates that chronically elevated GCs carry a variety of physiological costs, more study is needed to know whether GCs can be used as an index of human impact on population health or trend. / Forestry, Faculty of / Graduate

In contrast to most teleost fish that are ammoniotelic, the gulf toadfish (Opsanus beta) is both facultatively ureogenic and ureotelic. In vivo pharmacological manipulations were used to show that lowering circulating cortisol levels or blocking glucocorticoid receptors (GR) enhanced both urea excretion and urea pulse size. These findings demonstrated that changes in pulsatile urea excretion in the toadfish are mediated by the permissive action of cortisol through GRs. Measurement of urea transport across isolated basolateral gill membranes revealed a cortisol-sensitive carrier mechanism. Cortisol infusion in vivo significantly reduced urea transport capacity, suggesting that cortisol inhibits the recruitment of urea transport proteins (UT) to the basolateral membrane to ultimately decrease the size of the urea pulse in toadfish. A 1.2 kb fragment of the upstream transcription start site for the toadfish urea transporter (tUT) gene was isolated and in silico analysis revealed the presence of several putative glucocorticoid response element (GRE) half sites. Toadfish provided with this regulatory sequence in a reporter gene construct showed increased reporter gene transcription driven by cortisol. The data indicated that cortisol-mediated upregulation of tUT mRNA by GREs may be necessary to maintain tUT activity. Four Rhesus (Rh) glycoproteins (Rhag, Rhbg, Rhcg1, Rhcg2) were isolated from toadfish; these sequences grouped with those of other vertebrates coding for membrane channels that transport ammonia. In vivo increases in circulating cortisol reduced branchial Rh glycoprotein expression and decreased ammonia excretion. These changes were accompanied by cortisol-induced increases in glutamine synthetase activity, an enzyme that captures ammonia for urea synthesis. Taken together, the data indicated that cortisol reduces the loss by branchial excretion of ammonia, instead favouring biochemical pathways that convert ammonia to urea. This thesis confirms that nitrogen excretion in toadfish is controlled and regulated in fashions unlike those in other teleosts. The results demonstrate the importance of the GR signaling pathway in mediating changes in both urea and ammonia transport through molecular mechanisms. As a whole, the data provide a new understanding of branchial nitrogen excretion in the gulf toadfish and enhance our evolutionary perspective of the integrated biological systems involved in nitrogen excretion in fish.

The daughters of women with a history of depression are at heightened risk for a range of mental health problems. The present study investigated emotion regulation, cortisol reactivity to stress, and interpersonal competence as potential indicators of risk in adolescent girls at high versus low risk for depression. Participants were a community sample of 47 girls and their mothers (27 high risk and 20 low risk). Mothers and daughters had been interviewed to assess diagnostic history as part of a previous longitudinal study. In the current study, daughters completed the Trier Social Stress Test for Children (TSST-C) and cortisol samples were collected before and after exposure to this psychosocial stressor. Both mothers and daughters completed self-report questionnaires and daughters were re-assessed using the Depressive Disorders module of the Kiddie Schedule for Affective Disorders and Schizophrenia. High risk mothers were also interviewed to assess the timing and chronicity of their depressive episodes during their daughters’ lifetime. High and low risk girls had equivalent ratings of self-reported stress following the TSST-C, but different physiological responses. Girls at high risk for depression showed a blunted cortisol response to the TSST-C whereas low risk girls showed a normal cortisol response. High risk status for depression predicted a blunted cortisol response to stress, which predicted difficulties with emotion regulation; difficulties with emotion regulation in turn predicted a greater number of self-reported depressive symptoms. These results suggest that maternal depression may act as a stressor that compromises stress-response system functioning in daughters and produces related difficulties with emotion regulation.

The proposed study examined the relationship between parental anxiety, measured both subjectively (via self-report questionnaires) and objectively (via salivary cortisol) and the child's feeding progress. Children diagnosed with a feeding disorder were recruited with their parents at Our Children's House at Baylor (n=19; 11 females, 8 males). The patients and their parents were housed in the clinic for an eight-week intensive multidisciplinary pediatric feeding disorder treatment program. Calorie intake was recorded daily as outcome measures of treatment progression. Parental anxiety was measured by the Pediatric Inventory for Parents (PIP), state anxiety on the State Trait Anxiety Inventory (STAI), and by salivary cortisol at three different time points. The present study attempted to examine whether parental feeding (phase three of treatment program) would continue to cause a decrease in the child's caloric intake. In averaging ten meals prior to parental feeding in comparison to the average of ten meals following parental feeding, there was no significant difference as measured by a t-test. Paired t-tests examined parental anxiety from time one to time two and found that salivary cortisol increased significantly t(15) = -6.07, p = .000 from Time 1 (M = 2.30, SD = 1.64) to Time 2 (M = 5.24, SD = 2.58). This demonstrated that while parental anxiety increased as measured by salivary cortisol, the children continued to make improvements. This may be the result of the multidisciplinary feeding program which encompassed a strong behavioral component and parent training. Even though the current results did not demonstrate a direct relationship between parental stress and caloric intake, parental stress as measured by salivary cortisol did increase.

O trabalho noturno e a alternância de turnos são identificados como fatores de maximização de efeitos negativos na saúde do trabalhador, como o estresse e a fadiga, por dificultarem a adaptação do ritmo circadiano do cortisol ao de trabalho. Objetivo: investigar o efeito do esquema de trabalho em turnos fixo e alternante e noturno de enfermeiros nos índices de estresse ocupacional e fadiga e na expressão circadiana do cortisol salivar. Método: estudo observacional de corte transversal e abordagem quantitativa dos dados estruturado com base no referencial teórico de Cooper. Realizado com 104 enfermeiros das Unidades de Emergência e Bloco Cirúrgico de hospital de ensino público do Estado de São Paulo e outro de Minas Gerais, no período de janeiro a março de 2017. Índices de estresse e fadiga foram mensurados por meio da aplicação de dois instrumentos: o Inventário de Estresse em Enfermeiros e a Escala de Avaliação de Fadiga, ambos validados para utilização no Brasil. A quantificação do cortisol salivar foi realizada por meio da técnica de ELISA. O projeto foi aprovado pelo Comitê de Ética em pesquisa sob protocolo. 55695416.7.0000.5393. Resultados: 66,67% dos enfermeiros trabalhavam em esquema de turnos alternantes e 39,39% eram fixos no turno matutino. Constatou-se 50,8% apresentaram alto índice de estresse e 46,03% fadiga. Não foram observadas associações estatisticamente significativas entre índices de cortisol salivar, turno de trabalho, esquema de turno fixo ou alternante, estresse e fadiga. Entretanto, profissionais de enfermagem de unidades críticas que trabalhavam em esquema de turnos alternante e matutino apresentaram tendência a mais altos índices de estresse e fadiga e menor secreção de cortisol ao longo do dia de trabalho do que aqueles dos turnos fixo e noturno. A fadiga mostrou-se significativa e positivamente correlacionada com a secreção total de cortisol no período da manhã. Conclusão: Os achados do presente estudo fornecem evidências de uma dessincronização do eixo HipotálamoHipófise-Adrenal em enfermeiros dos turnos alternante e matutino e, consequentemente, maior susceptibilidade destes ao desenvolvimento de doenças cardíacas, metabólicas e imunológicas / Night-work and shiftwork are identified as maximizing negative effects on worker health, such as stress and fatigue, by making it difficult to adapt the circadian rhythm of cortisol to work. Objective: to investigate the effect of the fixed and alternating and nocturnal shifts of nurses on the occupational stress index, fatigue and circadian expression of salivary cortisol. Method: observational, cross-sectional and quantitative study based on Cooper\'s theoretical framework. Performed with 104 nurses from the emergency units and surgical center of a public teaching hospital in the State of São Paulo and another from Minas Gerais, from January to March, 2017. Stress and fatigue indexes were measured using two instruments, the Nurses\' Stress Inventory and the Fatigue Assessment Scale, both of which were validated and salivary cortisol quantification was performed by ELISA assay. The project was approved by the Research Ethics Committee under protocol. 55695416.7.0000.5393. Results: 66.67% of the nurses worked on alternating shifts and 39.39% were fixed on the morning shift. It was found that 50.8% of the nurses had a high stress index and 46.03% presented fatigue. There were no statistically significant associations between salivary cortisol index, shiftwork, fixed or alternating shift scheme, stress and fatigue. However, nursing professionals from critical units who worked in an alternating and morning shift schedule showed a trend towards higher levels of stress and fatigue and lower cortisol secretion throughout the workday than fixed and night shift workers. Fatigue was significantly and positively correlated to overall morning cortisol. Conclusions: The findings of the present study provide evidence of a hypothalamic-pituitary-adrenal axis desynchronization in nurses of the alternating and morning shift and, consequently, a greater susceptibility of these to the development of cardiac, metabolic and immunological diseases

Este trabalho teve como objetivo principal investigar o desempenho das funções executivas (FEs), a relação com a velocidade de processamento da informação e com medidas subjetivas e fisiológica do estresse em indivíduos diagnosticados com Esclerose Múltipla (EM) com incapacidade leve e moderada, avaliada pela Expanded Disability Status Scale (EDSS). O primeiro estudo corresponde a uma revisão sistemática da literatura sobre o estresse e as FEs na EM. No segundo estudo, foram apresentados os dados da comparação entre grupos no desempenho FEs e as correlações entre a cognição e a velocidade de processamento da informação. Os grupos estudados foram: controles saudáveis (n = 35); EM com EDDS 3 (n = 37); EM com EDSS entre 4-6 (n = 32). O grupo de EM com EDSS entre 4-6 apresentou pior desempenho em controle inibitório e planejamento em comparação aos demais grupos, sendo que as correlações significativas entre a velocidade de processamento da informação e o desempenho das FEs estiveram mais presentes no grupo controle e de EM com EDDS 3. No terceiro estudo, foram apresentados dados das correlações entre as FEs e medidas de estresse através da percepção e do cortisol no grupo de controles saudáveis (n = 35) e de EM (n = 69). Os dados mostraram mínimas associações entre o cortisol, especialmente, no controle inibitório e a influência de baixos níveis de cortisol na resolução de problemas⁄flexibilidade cognitiva no grupo de EM em comparação ao grupo de controles saudáveis. Concluiu-se que o desempenho das FEs pode estar associado ao nível de incapacidade medido pela EDSS de indivíduos diagnosticados com EM, sendo que a velocidade de processamento da informação parece não estar associada, de forma significativa, às FEs de indivíduos com maior incapacidade. Na presente amostra, o estresse percebido não esteve associado às FEs, porém, níveis baixos de cortisol parecem prejudicar determinados subcomponentes executivos no grupo de EM. Dados da revisão sistemática mostraram uma associação indireta entre a percepção do estresse a o desempenho das FEs após diferentes intervenções. / The main objective of this study was to investigate the performance of executive functions (EF), the relationship with information processing speed and subjective and physiological measures of stress in individuals diagnosed with Multiple Sclerosis (MS); mild and moderate disability, evaluated by Expanded Disability Status Scale (EDSS). Initially, the literature on stress and EF in MS is systematically reviewed. In the second study, we present the data of the comparison between groups in the EF performance and the correlations between the cognition and the speed of information processing. The groups studied were: healthy controls (n = 35); MS with EDDS 3 (n = 37); MS with EDSS between 4-6 (n = 32). The MS group with EDSS between 4-6 had worse performance in inhibitory control and planning in comparison to the other groups, and the significant correlations between the information processing speed and the performance of the EF were more evident in the control and MS groups with EDDS 3. In the third study, data are presented on correlations between EF and stress measures through perception and cortisol in healthy controls (n = 35) and MS (n = 69). The data showed minimal associations between cortisol, especially the influence of low cortisol levels on inhibitory control and problem-solving-cognitive flexibility in the MS group compared to the healthy controls group. We concluded that the performance of EF may be associated with the level of disability measured by the EDSS of individuals diagnosed with MS, and the speed of information processing seems not to be significantly associated to the EF of individuals with greater disability. In the present sample, perceived stress was not associated with EF, but low levels of cortisol appear to impair certain executive subcomponents in the MS group. However, data from the systematic review showed an indirect association between the perception of stress and the performance of EF after different interventions.

abstract: Stress in individuals presents in various forms and may accumulate across development to predict maladaptive physical and psychological outcomes, including greater risk for the onset of internalizing symptoms. Early life stress, daily life experiences, and the stress response of the hypothalamic-pituitary-adrenal (HPA) axis have all been examined as potential predictors of the development of psychopathology, but rarely have researchers attempted to understand the covariation or interaction among these stress domains using a longitudinal design when looking at the influence of stress on internalizing psychopathology. Further, most research has examined these processes in adulthood or adolescence with much less attention given to the influence of these dynamic stress pathways in childhood. Guided by the biopsychosocial model of stress, this study explored early life stress, daily life stress, diurnal cortisol (cortisol AM slope), and internalizing symptoms in a racially/ethnically and socioeconomically diverse sample of twins participating in an ongoing longitudinal study (N=970 children; Arizona Twin Project; Lemery-Chalfant et al. 2013). An additive model of stress and a stress sensitization framework model were considered as potential pathways of stress to internalizing symptoms in middle childhood. Based on a thorough review of relevant literature, it was expected that each stress indicator would individually predict internalizing symptoms. It was also predicted that early life stress would moderate the associations between diurnal cortisol and internalizing symptoms, as well as daily life stress and internalizing symptoms. Multilevel modeling analyses showed that early life stress and cortisol AM slope, but not daily life stress, predicted internalizing symptoms. Early life stress did not moderate the associations between daily life stress and internalizing symptoms or cortisol AM slope and internalizing symptoms. Results support independent additive contributions of both physiological stress processes and early life parental stressors in the development of internalizing symptoms in middle childhood. Future investigation is needed to better understand the sensitizing effects of early parental life stress during this developmental stage. / Dissertation/Thesis / Masters Thesis Psychology 2020

Teams are being used more in organizations to do important work. However, both positive and negative effects come with the increased use of teams. One problem is the "bad apple" effect where a highly disagreeable team mate, for example, damages team performance. This research aims to study how this person damages team performance and what can be done to minimize the negative impact. I propose that a disagreeable teammate negatively impacts team affective states which in turn give rise to defensive behaviors among teammates. These defensive behaviors impact team processes which in turn impact the team's performance. In addition, I propose that team interdependence moderates the impact of disagreeableness on teammate affective reactions such that teammates in less interdependent contexts will react less negatively to the "bad apple." I designed a 2x2 lab experiment with a confederate, or trained research participant, to test these hypotheses. I manipulated disagreeableness through the behaviors of the confederate and I manipulated interdependence through the information, goals, and rewards of the teams. Results support all the hypothesized relationships. Of note, I found that interdependence interacted with disagreeableness to predict team affective reactions as measured by salivary cortisol - a well established biomarker for affective reactions. I also found support for a mediating model using team core affect or affective culture mediating the impact of disagreeableness on team process. Finally, I found support for a mediated moderation model demonstrating that the moderation of interdependence and disagreeableness on team process was mediated by team cortisol. However, the impact on process was in the opposite direction than expected. Namely, that more interdependent teams had higher processes despite elevated cortisol levels indicating a negative affective, or stress reaction. This counterintuitive finding has implications for future research attempting to discover useful methods of minimizing the impact of a disagreeable teammate on the team.

Chronic stress exposure is hypothesized to increase the risk for developing a mental or physical disease, which can be summarized as an overall increased vulnerability to adverse health conditions. This thesis shows one potential pathway of stress exposure entering the body via activation of the hypothalamus pituitary adrenal (HPA) axis and the interaction between HPA axis and immune activation. Chronic stress caused by work overload or the experience of stressful life events was associated with altered levels of cortisol, the main effector hormone of the HPA axis. Further, chronic stress was shown to effect the distribution of neutrophils, a leukocyte subtype known for its defence properties as well as for its side effects of tissue damage. Additional analyses support a theory that HPA axis and immune cells work in synergy to adapt the organism to chronic stress exposure and therefore represent one pathway how stress can cause altered immune defence toward an increased vulnerability to disease.