Research has centred on multidimensional chromatographic techniques which utilise the high specificity of immunoaffinity chromatography for extraction of analytes from complex biological matrices. On-line immunoaffinity chromatography-high performance liquid chromatography-mass spectrometry (IAC-HPLC-MS) systems (IAC and HPLC coupled via a loop interface) were developed for the confirmatory analysis of the corticosteroids dexamethasone and flumethasone with MS detection. Utilising an atmospheric pressure chemical ionisation (APCI) LC-MS interface, dexamethasone was confirmed in both spiked and post administration equine urine samples, with a detection limit of 0.1 ug 1-l. Detection by quadrupole ion trap mass spectrometry (ITMS) using a particle beam (PB) interface was performed for dexamethasone and flumethasone in post administration equine urine samples with high precision (6.9-7.4 %) with limits of detection in the range 3-4 ug 1-l. Studies were also conducted in this work into the antibody crossreactivity and non-specific binding of corticosteroids on a HEMA bound anti-dexamethasone lAC column. On-line IAC-HPLC and IAC-HPLC-GC have been developed and assessed for the determination of testosterone in equine urine. A novel approach to interfacing lAC with HPLC being achieved using a porous graphitic carbon (PGC) column. The IAC-HPLC system developed was used for sample pre-treatment for combustion isotope ratio mass spectrometry analysis. The IAC-HPLC and IAC-HPLC-GC systems finally being coupled with mass spectrometry to enable confirmation of the endogenous steroid at 0.5 ug 1-l and 1 ug 1-l respectively in stripped equine urine.

Within animal societies, individuals often differ greatly in their level of investment in cooperative activities. Individuals are predicted to show high cooperative investment if high levels of relatedness lead to large indirect fitness benefits, or if differences in individual characteristics such as age, sex, rank, or body condition increase the direct fitness benefits of helping. However, individual differences often persist after these differences are controlled for; a residual variation that remains unexplained. Understanding the proximate mechanisms underlying variation in behaviour can give novel insights into the selection pressures shaping behavioural differences. This suggests that a research focus onto the proximate mechanisms underpinning cooperative behaviours is needed to further our understanding of why individuals behave differently within social groups. In this thesis, I address this shortfall in understanding by investigating hormonal variation alongside individual differences in cooperative investment in the banded mongoose (Mungos mungo). Banded mongooses are a highly social carnivore with two highly conspicuous forms of cooperative offspring care that are easily measurable and show large inter-individual variation. In chapter 3, I demonstrate a negative carry-over effect of investment in offspring care in consecutive breeding attempts. I show that this carry-over effect is mediated by variation in glucocorticoid concentrations, which may be attributable to the energetic costs of helping. Glucocorticoids predict investment in offspring care, suggesting that this mechanism may drive inter-individual variation in cooperative investment. In chapter 4, I find evidence for a testosterone mediated trade-off between offspring care and mating effort, which suggests that inter-individual differences may also be driven by variation in the costs of helping attributable to missed mating opportunities. In chapter 5, I use simulated territorial intrusions to show that there is unlikely to be a trade-off between offspring care and territory defence in banded mongoose societies. However, carers and non-carers show a differential physiological response to territorial intrusion, suggesting that there may be a more subtle behavioural trade-off that occurs post-intrusion. In chapter 6, I find evidence for consistent individual differences in both cooperative and competitive behaviours, which suggests that individual differences in adult behaviour may be determined by early-life effects. Individual differences in cooperative investment are positively correlated, suggesting that individuals are not specialised to different cooperative activities, but are consistently either helpful or selfish. Together, these results give insights into the selection pressures shaping individual differences and highlight endocrine research as a valuable tool in understanding the evolution of cooperative societies.

Testosterone levels change in response to a variety of social situations including, sexual and challenge situations. Yet, little is known about the role of testosterone dynamics in in young adults in romantic relationships. Furthermore, the effect of compatibility of the relationship dyad on testosterone reactivity in response to social-challenge is unknown. Prior studies suggest that attachment levels may predict testosterone responsivity during stressors such as social challenge. What is missing from the literature is whether testosterone response to social-challenge is specifically modified within the confines of an attachment relationship, such as within romantic couples. I measured salivary testosterone in healthy romantically involved young adult couples in response to a examined romantic couples during a standardized laboratory stressor in the SPIT lab. Testosterone was measured repeatedly from saliva in both members of each dyad and assayed using an enzymeimmunoassay. Participants completed questionnaires measuring perceived relationship commitment, support, satisfaction, and passion. This was collectively described as relationship compatibility. I revealed that participants in romantic relationships showed significant testosterone response to the Trier Social Stress Test (TSST). Testosterone levels of the participant were moderated by testosterone levels of the supporter during the socialchallenge, such that the supporter’s response was coupled with their partner’s testosterone response to stress. When the couples reported high-compatibility, their testosterone profiles were more coupled than for couples reporting low-compatibility. Findings fit within the challenge hypothesis and extend it in interesting ways. Testosterone may help an individual confront a challenge, and, more interestingly, testosterone may help a couple confront a challenge together.

Stress often precedes the onset of physical and mental health disorders, leading to costly and extended disability and even increased risk for death. I investigate psychosocial and endocrine precursors to stress responses, specifically examining the causal effects of status-relevant factors that modulate endocrine, affective, and behavioral responses to social-evaluative stressors. For example, while high social status reduces stress responses in numerous species, this stress-buffering effect of status may dissipate or even reverse during times of hierarchical instability. Similarly, some research links testosterone to reduced stress system activity, but correlational research indicates that higher testosterone is related to increased stress responses in threatening social situations. In each case, the causal influence of these psychosocial (status and hierarchy stability) and endocrine (testosterone) antecedents to stress responses was unclear. Results from this work (Chapter 2) reveal that high status in a stable hierarchy buffered stress responses and improved behavioral responses to the stressor, but high status in an unstable hierarchy boosted stress responses and did not lead to better performance. This general pattern of effects was observed across endocrine (cortisol and testosterone), psychological (feeling in control), and behavioral (competence, dominance, and warmth) responses to the stressor. Further (Chapters 4 & 6), exogenous testosterone treatment caused increased motivated persistence – which can help persevere through stressful encounters – but, once exposed to a stressor, testosterone caused increased cortisol reactivity, increased negative affect, and decreased motivation in response to social-evaluative stress, especially for individuals high in trait dominance. This work provides evidence of the causal effects of psychosocial and endocrine factors on stress responses and demonstrates the importance of considering these status-relevant precursors when investigating stress within social contexts.

O objetivo da presente dissertação foi investigar o efeito da territorialidade e do nível do adversário nas respostas hormonais e comportamentais de jogadores de basquetebol. Para tanto, foram realizados dois estudos. No primeiro, investigou-se o efeito da territorialidade nas respostas hormonais e comportamentais decorrentes de jogos oficiais de basquetebol. Dezoito jogadores, do sexo masculino, de duas equipes da categoria sub-19 (ranqueadas em primeiro e segundo lugar na competição) foram avaliados. As equipes jogaram entre si e, portanto, cada equipe realizou um jogo \"em casa\" e um jogo \"fora de casa\". Amostras de saliva foram coletadas antes e após as duas partidas, para análise dos hormônios testosterona (T) e cortisol (C). Antes do aquecimento, os atletas responderam um questionário de ansiedade pré-competitiva, (Competitive State Anxiety Inventory-2; CSAI-2), e 30 minutos após a partida, classificaram a magnitude do esforço através do método da percepção subjetiva de esforço da sessão (PSE da sessão). A concentração de T PRÉ-jogo foi maior na condição \"casa\" (versus \"fora de casa\"); verificou-se um aumento da concentração de T e C do momento PRÉ- para o PÓS-jogo, independentemente do local do jogo; correlações significantes foram apresentadas entre as respostas hormonais e comportamentais. Esses resultados sugerem a ocorrência do fenômeno da territorialidade, e confirmam que a competição é um evento estressor capaz de alterar a concentração hormonal. No segundo estudo, a influência do nível do adversário nas respostas hormonais e comportamentais de jogadores de basquetebol foi investigada. Dez atletas de uma equipe sub-19 foram avaliados em três jogos oficiais distintos e em uma sessão de treinamento (ST). Em cada um dos jogos oficiais, a equipe enfrentou adversários de diferentes níveis de qualificação, a saber: jogo fácil (JF), jogo médio (JM) e jogo difícil (JD). A classificação do nível do adversário foi realizada por um membro da comissão técnica no início da temporada e monitorada de acordo com a posição de cada uma das equipes durante o campeonato. Foram realizadas coletas de saliva antes e após as quatro condições (três jogos e uma sessão de treinamento) para análise da concentração de T e C. Antes do aquecimento, em todas as condições, os jogadores responderam o questionário CSAI-2 e, aproximadamente 30 minutos após o jogo, responderam a PSE da sessão. A concentração de T aumentou de PRÉ para PÓS no ST e JD; a concentração de T PRÉ-JD foi maior em relação a situação PRÉ-ST. A concentração de C aumentou de PRÉ para PÓS em ST, JM e JD, e a concentração C PRÉ- e PÓS-JD foi maior quando comparada aos mesmos momentos na ST. As ansiedades somática e cognitiva se mostraram maiores no JM e JD em relação ao JF. A autoconfiança foi maior na ST quando comparado com o JM e JD. A PSE da sessão foi maior nos JM e JD em relação à ST. Os resultados do presente estudo indicam que jogos oficiais contra adversários de diferentes níveis podem promover diferentes respostas hormonais e perceptuais / The aim of this dissertation was to investigate the effect of territoriality and the level of opponent on hormonal and behavioral responses in basketball players. Two studies were conducted. In the first one, in order to investigate the effect of territoriality on hormonal and behavioral responses from official basketball matches, eighteen male players, from two under-19 teams (ranked matches in first and second place in the competition) were investigated. The teams played against each other, so each team performed a game \"at home\" and \"away from home\" game. Saliva samples were collected before and after the two matches for hormone analysis [testosterone (T) and cortisol (C)]. Before warm-up, a pre-competitive anxiety questionnaire was answered (Competitive State Anxiety Inventory-2, CSAI-2), and 30 minutes after the matches, the athletes classified the magnitude of effort by means of session-RPE. It was observed a higher value for T PRE game during \"at home\" condition when compared to \"away from home\"; there was a rise in T and C concentrations from moment PRE to POST in both conditions (\"at home\" and \"away\"); significant correlations were observed between hormonal and behavioral responses. These results show the occurrence of territoriality phenomenon, demonstrated by the higher T concentration during \"at home\" PRE game moment, and that official competitive condition is a stressor event capable of altering hormonal concentration. In the second study, the purpose was to verify the influence of the level of the opponent on hormonal and behavioral responses in basketball players. Twelve athletes from an under-19 team were evaluated in three different official matches and one training session (TS). Each official match was played against an opponent with different level of quality: weak match (WM), medium match (MM) and strong match (SM). The classification of the level of the opponent was made by a member of the coaching staff at the beginning of the competitive season and monitored in accordance with the position of the teams during the championship. Saliva samples were collected before and after the four conditions (three games and a training session) for T and C analyzing. Before warm-up, players answered the CSAI-2 questionnaire and approximately 30 minutes after the game, answered session-RPE. It was demonstrated an increase in T concentration from PRE to POST moments in response to TS and SM conditions and T concentration during PRE-SM was higher when compared to PRE-TS condition. The concentration of C increased from PRE to POST moments during TS, MM, and SM and C concentration during PRE and POST-SM were higher compared to the same moments for TS condition. Athletes reported higher values of somatic and cognitive anxieties in MM and SM when compared to WM condition. Self-confidence values were greater during TS compared to MM and SM. Session-RPE presented higher scores in MM and SM compared to TS. The results of the present investigation indicate that official games against opponents of different levels may promote hormonal and perceptual responses of distinct magnitudes

O objetivo da presente dissertação foi investigar o efeito da territorialidade e do nível do adversário nas respostas hormonais e comportamentais de jogadores de basquetebol. Para tanto, foram realizados dois estudos. No primeiro, investigou-se o efeito da territorialidade nas respostas hormonais e comportamentais decorrentes de jogos oficiais de basquetebol. Dezoito jogadores, do sexo masculino, de duas equipes da categoria sub-19 (ranqueadas em primeiro e segundo lugar na competição) foram avaliados. As equipes jogaram entre si e, portanto, cada equipe realizou um jogo \"em casa\" e um jogo \"fora de casa\". Amostras de saliva foram coletadas antes e após as duas partidas, para análise dos hormônios testosterona (T) e cortisol (C). Antes do aquecimento, os atletas responderam um questionário de ansiedade pré-competitiva, (Competitive State Anxiety Inventory-2; CSAI-2), e 30 minutos após a partida, classificaram a magnitude do esforço através do método da percepção subjetiva de esforço da sessão (PSE da sessão). A concentração de T PRÉ-jogo foi maior na condição \"casa\" (versus \"fora de casa\"); verificou-se um aumento da concentração de T e C do momento PRÉ- para o PÓS-jogo, independentemente do local do jogo; correlações significantes foram apresentadas entre as respostas hormonais e comportamentais. Esses resultados sugerem a ocorrência do fenômeno da territorialidade, e confirmam que a competição é um evento estressor capaz de alterar a concentração hormonal. No segundo estudo, a influência do nível do adversário nas respostas hormonais e comportamentais de jogadores de basquetebol foi investigada. Dez atletas de uma equipe sub-19 foram avaliados em três jogos oficiais distintos e em uma sessão de treinamento (ST). Em cada um dos jogos oficiais, a equipe enfrentou adversários de diferentes níveis de qualificação, a saber: jogo fácil (JF), jogo médio (JM) e jogo difícil (JD). A classificação do nível do adversário foi realizada por um membro da comissão técnica no início da temporada e monitorada de acordo com a posição de cada uma das equipes durante o campeonato. Foram realizadas coletas de saliva antes e após as quatro condições (três jogos e uma sessão de treinamento) para análise da concentração de T e C. Antes do aquecimento, em todas as condições, os jogadores responderam o questionário CSAI-2 e, aproximadamente 30 minutos após o jogo, responderam a PSE da sessão. A concentração de T aumentou de PRÉ para PÓS no ST e JD; a concentração de T PRÉ-JD foi maior em relação a situação PRÉ-ST. A concentração de C aumentou de PRÉ para PÓS em ST, JM e JD, e a concentração C PRÉ- e PÓS-JD foi maior quando comparada aos mesmos momentos na ST. As ansiedades somática e cognitiva se mostraram maiores no JM e JD em relação ao JF. A autoconfiança foi maior na ST quando comparado com o JM e JD. A PSE da sessão foi maior nos JM e JD em relação à ST. Os resultados do presente estudo indicam que jogos oficiais contra adversários de diferentes níveis podem promover diferentes respostas hormonais e perceptuais / The aim of this dissertation was to investigate the effect of territoriality and the level of opponent on hormonal and behavioral responses in basketball players. Two studies were conducted. In the first one, in order to investigate the effect of territoriality on hormonal and behavioral responses from official basketball matches, eighteen male players, from two under-19 teams (ranked matches in first and second place in the competition) were investigated. The teams played against each other, so each team performed a game \"at home\" and \"away from home\" game. Saliva samples were collected before and after the two matches for hormone analysis [testosterone (T) and cortisol (C)]. Before warm-up, a pre-competitive anxiety questionnaire was answered (Competitive State Anxiety Inventory-2, CSAI-2), and 30 minutes after the matches, the athletes classified the magnitude of effort by means of session-RPE. It was observed a higher value for T PRE game during \"at home\" condition when compared to \"away from home\"; there was a rise in T and C concentrations from moment PRE to POST in both conditions (\"at home\" and \"away\"); significant correlations were observed between hormonal and behavioral responses. These results show the occurrence of territoriality phenomenon, demonstrated by the higher T concentration during \"at home\" PRE game moment, and that official competitive condition is a stressor event capable of altering hormonal concentration. In the second study, the purpose was to verify the influence of the level of the opponent on hormonal and behavioral responses in basketball players. Twelve athletes from an under-19 team were evaluated in three different official matches and one training session (TS). Each official match was played against an opponent with different level of quality: weak match (WM), medium match (MM) and strong match (SM). The classification of the level of the opponent was made by a member of the coaching staff at the beginning of the competitive season and monitored in accordance with the position of the teams during the championship. Saliva samples were collected before and after the four conditions (three games and a training session) for T and C analyzing. Before warm-up, players answered the CSAI-2 questionnaire and approximately 30 minutes after the game, answered session-RPE. It was demonstrated an increase in T concentration from PRE to POST moments in response to TS and SM conditions and T concentration during PRE-SM was higher when compared to PRE-TS condition. The concentration of C increased from PRE to POST moments during TS, MM, and SM and C concentration during PRE and POST-SM were higher compared to the same moments for TS condition. Athletes reported higher values of somatic and cognitive anxieties in MM and SM when compared to WM condition. Self-confidence values were greater during TS compared to MM and SM. Session-RPE presented higher scores in MM and SM compared to TS. The results of the present investigation indicate that official games against opponents of different levels may promote hormonal and perceptual responses of distinct magnitudes

The basis for sex differences in cognitive ability remains poorly defined and controversial both scientifically and politically. One of the biological hypotheses on sex differences, of particular relevance to this thesis, concerns the role of gonadal steroids, specifically testosterone (T) and oestrogen, and their relationship to individual differences in the performance of specific cognitive tasks. In addition, the role that age-related changes in these hormones play in relation to generalised and pathological cognitive ageing in males is studied. It is important to determine whether decreases in T levels that occur with ageing in males are associated with age-related decreases in cognitive performance because T levels can potentially be modified. Males have consistently been found to outperform females on measures of visuo-spatial function; performance on the Vandenberg and Kuse Mental Rotation Test (MRT) shows the largest and most robust of sex differences. Gonadal steroids have both organisational and activational effects which contribute to both withinsex variability and between-sex differences in visuo-spatial cognition. As males age, endogenous plasma T levels decline gradually yet variably between individuals. Studies in older males show improvement in visuo-spatial cognition following T supplementation; however, it remains to be resolved whether decreases in endogenous T levels with ageing are associated with poorer MRT performance. Some recent studies in older males have reported positive correlations between measures of plasma T levels and cognitive functioning, including processing speed and executive function measures. These data are inconsistent, however, and important questions remain concerning, for example: the age at which the effect is strongest; whether there are different effects at different ages; whether there is an optimal level at which T levels affect particular abilities; and which abilities show the strongest association with endogenous plasma T levels. Increased intra-individual variability in performance on Choice Reaction Time (RT) tasks has recently been shown to be a strong predictor of cognitive functioning in university students. Methodological advances in the analyses of RT distributions has allowed for the calculation of robust estimates of intra-individual RT variability. The association between these estimates and cognitive performance in middle and older aged males, however, remains to be determined. Further, the association between endogenous plasma T levels and intra-individual RT variability in aged males is unknown. The thesis addresses these issues; firstly, through cross-sectional analyses of the associations between different measures of plasma T levels, learning and memory, processing speed, and executive function performance in a large population based sample of 1046 men aged between 35 and 81 years. Secondly, further cross-sectional analyses are reported from a subsequent study in a healthy sub-sample of 96 of these men on the associations between endogenous plasma T levels, MRT performance, constituent abilities related to MRT performance, and performance on composite measures of both processing speed and executive function. In a third study, these data are re-analysed in relation to intra-individual variability in RT performance. In light of the results of these studies, the role that age-related declines in plasma T levels play in relation to generalised age-related cognitive decline in males is discussed. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1330807 / Thesis (Ph.D.) -- University of Adelaide, School of Psychology and School of Medicine, 2008

Graduation date: 1996

Onset of puberty was observed in 12 bison bulls by the collection of semen at monthly intervals for 12 months beginning at 13 months of age. Onset of puberty was defined as the time in development when an ejaculate contained a minimum of 50x106 sperm showing at least 10% progressive motility. At each collection, data were recorded on body weight, semen quality, fecal testosterone concentration, and physical development. Semen was evaluated for gross motility, individual progressive motility, sperm morphology, sperm concentration and volume. From these data bison bulls attained onset of puberty at an average age of 16.5 months and an average body weight of 353 ± 52.8 kg. Age was the greatest determining factor for onset of puberty in this group of bulls. <p> Monthly abattoir collections of epididymal sperm (n=288) and testicular tissue (n=120) were evaluated to determine if bison bulls undergo seasonal changes in sperm production. Although epididymal sperm morphology did not give any indication of seasonal variation, the histological study of testicular tissue showed greater seminiferous tubule diameter (27.0 ± 4.3 ìm) during the breeding months (July, August and September) than during any other seasons. Semen collected at 4 different occasions during the year (June, November, January, and April) from live mature breeding bulls (n=21) was used to verify data collected from abattoir samples. Semen from mature bulls showed a significantly greater proportion of normal sperm in June than in November (73.8 ± 9.1%; 44.1 ± 24.3%), respectively. There was little improvement in sperm morphology at the January sampling but in April morphology improved to a level close to that observed in June. Fecal testosterone concentrations were highest in June (128.6 ± 67.4 ng/g) and lowest in April (48.5 ± 33.3 ng/g). Although there was no clear seasonal trend in sperm morphology from bulls sampled at the abattoir, mature bulls showed slight seasonal variations in semen quality.

Onset of puberty was observed in 12 bison bulls by the collection of semen at monthly intervals for 12 months beginning at 13 months of age. Onset of puberty was defined as the time in development when an ejaculate contained a minimum of 50x106 sperm showing at least 10% progressive motility. At each collection, data were recorded on body weight, semen quality, fecal testosterone concentration, and physical development. Semen was evaluated for gross motility, individual progressive motility, sperm morphology, sperm concentration and volume. From these data bison bulls attained onset of puberty at an average age of 16.5 months and an average body weight of 353 ± 52.8 kg. Age was the greatest determining factor for onset of puberty in this group of bulls. <p> Monthly abattoir collections of epididymal sperm (n=288) and testicular tissue (n=120) were evaluated to determine if bison bulls undergo seasonal changes in sperm production. Although epididymal sperm morphology did not give any indication of seasonal variation, the histological study of testicular tissue showed greater seminiferous tubule diameter (27.0 ± 4.3 ìm) during the breeding months (July, August and September) than during any other seasons. Semen collected at 4 different occasions during the year (June, November, January, and April) from live mature breeding bulls (n=21) was used to verify data collected from abattoir samples. Semen from mature bulls showed a significantly greater proportion of normal sperm in June than in November (73.8 ± 9.1%; 44.1 ± 24.3%), respectively. There was little improvement in sperm morphology at the January sampling but in April morphology improved to a level close to that observed in June. Fecal testosterone concentrations were highest in June (128.6 ± 67.4 ng/g) and lowest in April (48.5 ± 33.3 ng/g). Although there was no clear seasonal trend in sperm morphology from bulls sampled at the abattoir, mature bulls showed slight seasonal variations in semen quality.