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1.
Animal ; 18(4): 101112, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38518429

RESUMO

Feedlot cattle are at times exposed to high environmental temperatures. Faecal cortisol metabolites were related to possible indicators of heat stress that could be measured under field conditions: respiratory dynamics (respiration rate), body surface temperature and adaptive behaviours, such as water consumption, posture (standing, lying), and activity (eating, drinking and rumination). Twelve (12) yearling Black Angus steers were divided into two treatment groups: a hot treatment (HOT; n = 6) and a thermoneutral-treatment (TN; n = 6) and individually housed in a climate-controlled facility at The University of Queensland, Australia. In the TN treatment, all animals were exposed to an ambient temperature of 20.34 ± 0.25 °C, relative humidity 71.51 ± 3.26% and Temperature humidity index (THI) 66.91 ± 0.33 throughout. In the HOT treatment group, environmental conditions were exposed to different climatic phases from thermoneutral to hot conditions, where they remained for 7 d, and then returned to TN conditions in the recovery period. The dry bulb ambient temperature (TA) and relative humidity (RH) in the pens of cattle in the HOT treatment were increased from 28 °C (daily maximum ambient temperature) and 45% RH at 0700 h to a daily maximum TA and RH of 35 °C (daily maximum ambient temperature) and 50% (THI 77) at 1100 h, which was maintained until 1600 h, after which it declined until it reached the baseline at 2000 h. In both treatments, there was a significant decrease in faecal cortisol metabolite concentration from the start to the end of the experiments they adapted to the experimental facility. The concentration of faecal cortisol metabolites was greater in the HOT treatment, compared to the TN treatment during the heat exposure period, but there was no difference in the transition or recovery periods. Respiration rate was greater in the HOT treatment during heat exposure, and it increased with ambient dry bulb temperature above 26 °C, the latter being the upper critical temperature. Although positive correlations were detected between faecal cortisol metabolites and body surface temperature measurements, particularly the shoulder and rump, as well as standing time, panting score and drinking, a stepwise regression found that faecal cortisol metabolites were only significantly correlated with one variable, respiration rate. It is concluded that respiration rate is the best indicator of the stress induced by hot conditions for cattle.


Assuntos
Temperatura Corporal , Hidrocortisona , Bovinos , Animais , Temperatura Alta , Temperatura , Resposta ao Choque Térmico , Umidade
2.
Trials ; 22(1): 306, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902699

RESUMO

BACKGROUND: Patient-reported outcomes (PROs) are used in clinical trials to assess the effectiveness and tolerability of interventions. Inclusion of participants from different ethnic backgrounds is essential for generalisability of cancer trial results. PRO data collection should include appropriately translated patient-reported outcome measures (PROMs) to minimise missing data and sample attrition. METHODS: Protocols and/or publications from cancer clinical trials using a PRO endpoint and registered on the National Institute for Health Research Portfolio were systematically reviewed for information on recruitment, inclusion of ethnicity data, and use of appropriately translated PROMs. Semi-structured interviews were conducted with key stakeholders to explore barriers and facilitators for optimal PRO trial design, diverse recruitment and reporting, and use of appropriately translated PROMs. RESULTS: Eighty-four trials met the inclusion criteria, only 14 (17%) (n = 4754) reported ethnic group data, and ethnic group recruitment was low, 611 (13%). Although 8 (57%) studies were multi-centred and multi-national, none reported using translated PROMs, although available for 7 (88%) of the studies. Interviews with 44 international stakeholders identified a number of perceived barriers to ethnically diverse recruitment including diverse participant engagement, relevance of ethnicity to research question, prominence of PROs, and need to minimise investigator burden. Stakeholders had differing opinions on the use of translated PROMs, the impact of trial designs, and recruitment strategies on diverse recruitment. Facilitators of inclusive research were described and examples of good practice identified. CONCLUSIONS: Greater transparency is required when PROs are used as primary or secondary outcomes in clinical trials. Protocols and publications should demonstrate that recruitment was accessible to diverse populations and facilitated by trial design, recruitment strategies, and appropriate PROM usage. The use of translated PROMs should be made explicit when used in cancer clinical trials.


Assuntos
Neoplasias , Medidas de Resultados Relatados pelo Paciente , Ensaios Clínicos como Assunto , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Pesquisadores
3.
Horm Behav ; 117: 104606, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639386

RESUMO

For most cetacean species, there is little known about how an individual's physiology influences its behaviour. Humpback whales (Megaptera novaeangliae) are a good candidate to examine such links as they have a well-described distribution and behaviour, can be consistently sampled using remote biopsy systems, and have been the subject of several previous endocrine studies. The objective here was to examine whether a female humpback whale's social state (i.e. escorted by a male or not) is related to her endocrine condition, and whether male dominance ranking is related to testosterone levels. Skin and blubber biopsies were collected from the east and west Australian humpback whale populations in 2010-2016 (n = 252) at multiple times throughout the winter-spring breeding season. Steroid hormones were extracted from blubber and concentrations of progesterone (a marker for pregnancy), testosterone (a marker of male testicular activity) and oestradiol (a potential marker of ovarian activity) measured using enzyme-immunoassays. Principal escorts-the dominant males in mixed sex groups-had significantly higher blubber testosterone levels (mean ±â€¯SE; 1.43 ±â€¯0.20 ng/g wet weight) than subordinate, secondary escorts (0.69 ±â€¯0.06 ng/g wet weight). Females that were escorted by males typically possessed elevated blubber oestradiol levels (1.96 ±â€¯0.25 ng/g wet weight; p = 0.014); few were considered to be pregnant (p = 0.083). 'Unescorted' females displayed characteristically lower blubber oestradiol levels (0.56 ±â€¯0.06 ng/g wet weight). Together, these results are consistent with 'challenge hypothesis' theory and suggest the existence of associated reproductive patterns in humpback whales.


Assuntos
Jubarte/fisiologia , Comportamento Sexual Animal/fisiologia , Tecido Adiposo , Migração Animal/fisiologia , Animais , Austrália , Constituição Corporal/fisiologia , Feminino , Hormônios/análise , Hormônios/química , Hormônios/metabolismo , Masculino , Gravidez , Reprodução/fisiologia , Estações do Ano , Pele/química , Pele/metabolismo , Testosterona/análise , Testosterona/metabolismo
4.
Gen Comp Endocrinol ; 274: 37-49, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30605661

RESUMO

Blubber and respiratory vapour ('blow') are now commonly used for endocrine studies on cetaceans, primarily because they can be obtained using minimally invasive methods. For many species, these samples have yet to be validated for these purposes. The objective of this study was to examine the performance of blow and blubber hormone monitoring, relative to serum hormone monitoring, for evaluating the reproductive and adrenal condition of captive bottlenose dolphins (Tursiops spp.). Eighteen bottlenose dolphins were sampled five times for serum and blow and twice for blubber throughout a one-year period. Concentrations of progesterone, testosterone, oestradiol and cortisol were measured in each sample type. Hormone levels were examined in relation to dolphin age, sex, reproductive status, season, time of sample collection (morning/afternoon) and collection type (in- or out-of-water sampling). Patterns in hormone levels were similar for serum and blubber. For instance, in both sample types, progesterone levels were significantly higher in pregnant (serum: 34.10 ±â€¯8.64 ng/mL; blubber: 13.01 ±â€¯0.72 ng/g) than in non-pregnant females (serum: 0.32 ±â€¯0.09 ng/mL; blubber: 1.17 ±â€¯0.10 ng/g). This pattern was not detected in blow, primarily because seawater contamination, nylon sampling materials and variable sample volumes influenced measured concentrations. In addition, the respiratory water content of a blow sample is known to affect measured hormone levels. Two methods were trialled to control for variability in sample volumes and dilution: (1) normalising blow hormone concentrations relative to urea nitrogen levels (a potential endogenous standard), and (2) measuring the relative proportions (i.e. ratios) of blow hormones. These correction measures had little influence on blow hormone results. Further refinement of blow hormone monitoring methods is required before they can be used for reproductive or adrenal assessments of bottlenose dolphins. Blubber, on the other hand, should be a suitable proxy for serum when attempting to classify pregnancy status and male maturity in these species.


Assuntos
Golfinho Nariz-de-Garrafa/anatomia & histologia , Golfinho Nariz-de-Garrafa/metabolismo , Testes Respiratórios , Sistema Endócrino/metabolismo , Respiração , Animais , Golfinho Nariz-de-Garrafa/sangue , Feminino , Hormônios/sangue , Masculino , Modelos Estatísticos , Gravidez , Reprodução
5.
Gen Comp Endocrinol ; 261: 40-50, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29373814

RESUMO

Although southern hairy-nosed wombats (SHN wombats; Lasiorhinus latifrons) rarely breed in captivity, further knowledge of their reproductive physiology and behavior is likely to improve their breeding potential. This study examined the effect of seasonal variation and changes in social dynamics on the physiology and behavior of a captive population of male SHN wombats (n = 6). Seasonal changes in urinary testosterone metabolites (UTM), urinary cortisol metabolites (UCM), qualitative estimates of spermatorrhoea (QS), aggressive behavior and reproductive behavior were measured over an 11-month period. While there was no effect of month on QS (GLM ANOVA, P = 0.27), reproductive behavior (GLM ANOVA, P = 0.19) or aggressive behavior (Tukey pairwise comparisons), the secretion of UTM (GLM ANOVA, P = 0.051) was only marginally affected by season, compared to that reported for wild male SHN wombats. Mean UCM concentrations of July and August 2016 were significantly higher than those between October 2015 and January 2016 (Tukey pairwise comparisons). To examine social dynamics, two trials of animal positioning exchange with the enclosure system were implemented and behavioral data were examined for each trial over a six week period; UTM, UCM and general behaviors (n = 27) were measured for each trial. Neither UTM nor UCM concentration varied significantly (P ≥ 0.45) before and after the exchanges. "Scratching" decreased at the group level following the animal exchange in both trials, suggesting reduction in self-grooming may be a behavioral response to novel stimuli. UCM and UTM concentrations were both positively correlated with "standing still" and "body rub" behaviors. This may be evidence of a hormonal control of a "freezing behavioral response" to external stimuli and marking behavior, respectively. As there was no evidence that changing the social dynamics affected reproductive or agonistic behavior or hormone concentrations, it was concluded that captive male wombats in this study showed reduced reproductive seasonality compared to wild wombats and that animal exchange resulted in a behavioral response to novel stimuli but was not sufficient to affect testosterone or cortisol secretion, within the context of our study.


Assuntos
Comportamento Animal , Sistema Endócrino/fisiologia , Marsupiais/fisiologia , Estações do Ano , Comportamento Social , Animais , Feminino , Hidrocortisona/urina , Masculino , Marsupiais/urina , Reprodução , Testosterona/urina
7.
Gen Comp Endocrinol ; 250: 70-79, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28599837

RESUMO

This study reports the validation and use of enzyme immunoassays (EIA) to measure changes in plasma and urinary luteinizing hormone, testosterone metabolites (UTM) and cortisol metabolites (UCM) in captive southern hairy-nosed wombats (Lasiorhinus latifrons). GnRH agonist and ACTH agonist challenges were conducted to validate urinary testosterone (male wombat only) and cortisol (male and female wombats) EIAs. Following intra-muscular injection of 8-12µg buserelin (n=4 males), there was a significant increase in both plasma (P<0.001) and urinary testosterone concentrations (P<0.001) 60min and 21h after administration, respectively. Plasma LH levels were elevated (p<0.05) at 20min but there was no significant increase found in urinary LH concentrations after injection. Intra-muscular injection of Synacthen® Depot (250µg) (n=3 males, 3 females) resulted in a significant increase (p<0.05) in plasma cortisol secretion 15min and in urinary cortisol concentrations 3h post injection, respectively. Sex-related differences in cortisol secretion were also reported in this study. These findings indicate that (1) urinary LH might not be an appropriate index for describing the reproductive status in captive male L. latifrons, and (2) the UTM and UCM assays appear to be suitable for the assessment of the testicular steroidogenic capacity and the adrenocortical activity in captive southern hairy-nosed wombats, respectively.


Assuntos
Hidrocortisona/metabolismo , Hidrocortisona/urina , Hormônio Luteinizante/urina , Marsupiais/urina , Testosterona/urina , Hormônio Adrenocorticotrópico/agonistas , Hormônio Adrenocorticotrópico/farmacologia , Animais , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/farmacologia , Masculino , Testosterona/sangue
8.
Theriogenology ; 95: 33-41, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28460677

RESUMO

The synchrony and timing of reproductive events are crucially important factors to maximize individual and offspring survival, especially in seasonal environments. To increase our understanding of the physiological basis of seasonality and the influence of associated environmental factors (maximum temperature, day length and rate of day length change associated with different latitudes) on reproduction in Tasmanian devils, we reviewed records and research data from captive facilities throughout Australia in comparison to those from a wild population study (1974-1987). Overall, breeding activity began 2 weeks earlier in the captive than the wild population (week 5.7 ± 0.6 versus week 7.7 ± 0.5 for devils entering into estrus during the first two week phase; n = 24 and n = 23 respectively). If the timing of reproductive activity is considered against absolute day length rather than date, both the captive and wild populations displayed similar distributions (12.9 ± 0.7 h versus 13.0 ± 0.7 h respectively; P < 0.01) confirming day length as a proximal cue involved in eliciting a physiological response to trigger seasonal reproductive activity regardless of location. Wild devils had a higher breeding success (75%; n = 169 versus 43%; n = 115) and larger litter size (3.4 ± 0.9 versus 2.8 ± 1.1 joeys per litter) than captive devils (P < 0.05). Mean maximum temperature at the onset of reproductive activity (P < 0.05) was higher for the captive than the wild population (28.1 ± 4.0 °C versus 22.3 ± 2.7 °C respectively). The drivers for reproductive success in captive Tasmanian devils are likely multifactorial, but our results suggest that elevated temperatures associated with shifts in breeding activity and geographical location should be examined further.


Assuntos
Marsupiais/fisiologia , Reprodução/fisiologia , Estações do Ano , Animais , Animais Selvagens , Animais de Zoológico , Austrália , Espécies em Perigo de Extinção , Feminino , Geografia , Tamanho da Ninhada de Vivíparos , Masculino , Fotoperíodo , Temperatura
9.
Reprod Fertil Dev ; 29(11): 2235-2244, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28356183

RESUMO

The aim of the present study was to develop a protocol for the successful cryopreservation of Saltwater crocodile spermatozoa. Sperm cells were frozen above liquid nitrogen vapour in phosphate-buffered saline (PBS) containing either 0.3M trehalose, 0.3M raffinose or 0.3M sucrose and compared with glycerol (0.3-2.7M). Although the highest levels of mean post-thaw motility were observed following cryopreservation in 0.3M trehalose (7.6%) and 0.3M sucrose (7.3%), plasma membrane integrity (PI) was best following cryopreservation in 2.7M glycerol (52.5%). A pilot study then assessed the cytotoxicity of glycerol and sucrose prior to cryopreservation and revealed no loss of survival when spermatozoa were diluted in 0.68M glycerol or 0.2-0.3M sucrose once cryoprotectants were washed out with PBS or Biggers, Whitten and Whittingham medium containing sperm capacitation agents (BWWCAP). A final study refined the combined use of permeating (0.68 or 1.35M glycerol) and non-permeating (0.2 or 0.3M sucrose) cryoprotectants. Spermatozoa were cryopreserved in liquid nitrogen vapour at rates of approximately -21°Cmin-1 (fast freeze) or -6.0°Cmin-1 (slow freeze). Post-thaw survival was highest with a combination of 0.2M sucrose and 0.68M glycerol and when these cryoprotectants were washed out with BWWCAP, regardless of whether spermatozoa were frozen using a fast (motility 14.2±4.7%; PI 20.7±2.0%) or slow (motility 12.0±2.7%; PI 22±4%) cryopreservation rate.


Assuntos
Jacarés e Crocodilos , Criopreservação/métodos , Preservação do Sêmen/métodos , Espermatozoides , Animais , Crioprotetores/administração & dosagem , Masculino , Motilidade dos Espermatozoides , Sacarose/administração & dosagem , Trealose/administração & dosagem
10.
Res Vet Sci ; 107: 30-33, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27473971

RESUMO

This study reports the first documented clinical case of a spermatic granuloma and varicocele in a marsupial. Initial clinical presentation included gross morphological changes in the left scrotal cord, epididymis and testis. Ultrasonography of the scrotum and spermatic cord, and gross and histopathological examination after hemicastration, confirmed the condition as a spermatic granuloma affecting the left caput epididymis, with a varicocele in the left proximal spermatic cord, which was causing azoospermia and infertility. Semen quality and serum testosterone secretion following a GnRH challenge was assessed prior to, and following surgery. After hemi-castration, an increase in androgen secretion to within normal reference ranges for the koala was observed with a subsequent increase in semen production and sperm quality resulting in the sire of a pouch young, 12months later.


Assuntos
Granuloma/veterinária , Phascolarctidae , Varicocele/veterinária , Animais , Hormônio Liberador de Gonadotropina/farmacologia , Granuloma/diagnóstico , Granuloma/cirurgia , Masculino , Orquiectomia/veterinária , Análise do Sêmen/veterinária , Testosterona/sangue , Varicocele/diagnóstico , Varicocele/cirurgia
11.
Trials ; 17(1): 230, 2016 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27142835

RESUMO

BACKGROUND: Core outcome sets (COS) help to minimise bias in trials and facilitate evidence synthesis. Delphi surveys are increasingly being used as part of a wider process to reach consensus about what outcomes should be included in a COS. Qualitative research can be used to inform the development of Delphi surveys. This is an advance in the field of COS development and one which is potentially valuable; however, little guidance exists for COS developers on how best to use qualitative methods and what the challenges are. This paper aims to provide early guidance on the potential role and contribution of qualitative research in this area. We hope the ideas we present will be challenged, critiqued and built upon by others exploring the role of qualitative research in COS development. This paper draws upon the experiences of using qualitative methods in the pre-Delphi stage of the development of three different COS. Using these studies as examples, we identify some of the ways that qualitative research might contribute to COS development, the challenges in using such methods and areas where future research is required. RESULTS: Qualitative research can help to identify what outcomes are important to stakeholders; facilitate understanding of why some outcomes may be more important than others, determine the scope of outcomes; identify appropriate language for use in the Delphi survey and inform comparisons between stakeholder data and other sources, such as systematic reviews. Developers need to consider a number of methodological points when using qualitative research: specifically, which stakeholders to involve, how to sample participants, which data collection methods are most appropriate, how to consider outcomes with stakeholders and how to analyse these data. A number of areas for future research are identified. CONCLUSIONS: Qualitative research has the potential to increase the research community's confidence in COS, although this will be dependent upon using rigorous and appropriate methodology. We have begun to identify some issues for COS developers to consider in using qualitative methods to inform the development of Delphi surveys in this article.


Assuntos
Ensaios Clínicos como Assunto/métodos , Técnica Delphi , Determinação de Ponto Final , Projetos de Pesquisa , Consenso , Humanos , Resultado do Tratamento
12.
Health Qual Life Outcomes ; 14: 36, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26940027

RESUMO

BACKGROUND: The ICECAP measures potentially offer a broader assessment of quality of life and well-being, in comparison to measures routinely used in economic evaluation, such as the EQ-5D-3 L. This broader assessment may allow measurement of the full effects of an intervention or treatment. Previous research has indicated that the ICECAP-O (for older people) and EQ-5D-3 L measure provide complementary information. This paper aims to determine similar information for the ICECAP-A (for the entire adult population) in terms of whether the measure is a substitute or complement to the EQ-5D-3 L. METHODS: Data from the BEEP trial - a multi-centre, pragmatic, randomised controlled trial - were used. Spearman rank correlations and exploratory factor analytic methods were used to assess whether ICECAP-A and EQ-5D-3 L are measuring the same, or different, constructs. RESULTS: A correlation of 0.49 (p < 0.01) was found between the ICECAP-A tariff score and the EQ-5D-3 L index. Using the pooled items of the EQ-5D-3 L and the ICECAP-A a two factor solution was optimal, with the majority of EQ-5D-3 L items loading onto one factor and the majority of ICECAP-A items onto another. CONCLUSION: The results presented in this paper indicate that ICECAP-A and EQ-5D-3 L are measuring two different constructs and provide largely different, complementary information. Results showed a similarity to results presented by Davis et al. using the ICECAP-O. TRIAL REGISTRATION: ISRCTN 93634563.


Assuntos
Joelho , Medição da Dor/instrumentação , Dor/psicologia , Qualidade de Vida/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
13.
Qual Life Res ; 24(10): 2319-31, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25894061

RESUMO

PURPOSE: The ICECAP-A is a simple measure of capability well-being for use with the adult population. The descriptive system is made up of five key attributes: Stability, Attachment, Autonomy, Achievement and Enjoyment. Studies have begun to assess the psychometric properties of the measure, including the construct and content validity and feasibility for use. This is the first study to use longitudinal data to assess the responsiveness of the measure. METHODS: This responsiveness study was completed alongside a randomised controlled trial comparing three physiotherapy-led exercise interventions for older adults with knee pain attributable to osteoarthritis. Anchor-based methodologies were used to explore the relationship between change over time in ICECAP-A score (the target measure) and change over time in another measure (the anchor). Analyses were completed using the non-value-weighted and value-weighted ICECAP-A scores. The EQ-5D-3L was used as a comparator measure to contextualise change in the ICECAP-A. Effect sizes, standardised response means and t tests were used to quantify responsiveness. RESULTS: Small changes in the ICECAP-A scores were seen in response to underlying changes in patients' health-related quality of life, anxiety and depression. Non-weighted scores were slightly more responsive than value-weighted scores. ICECAP-A change was of comparable size to change in the EQ-5D-3L reference measure. CONCLUSION: This first analysis of the responsiveness using longitudinal data provides some positive evidence for the responsiveness of the ICECAP-A measure. There is a need for further research in those with low health and capability, and experiencing larger underlying changes in quality of life.


Assuntos
Osteoartrite/diagnóstico , Dor/diagnóstico , Perfil de Impacto da Doença , Idoso , Ansiedade/diagnóstico , Estudos Transversais , Depressão/diagnóstico , Feminino , Seguimentos , Humanos , Joelho , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pacientes/psicologia , Psicometria , Qualidade de Vida , Inquéritos e Questionários
14.
Aust Vet J ; 91(12): 534-537, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31027400

RESUMO

BACKGROUND: Stress can play a role in disease incidence in all species via immunosuppression and has been implicated as a contributing factor in significant infectious diseases of koalas. Faecal cortisol measurement may represent a non-invasive methodology for quantifying stress in koalas. METHODS: We used an ACTH (adrenocorticotropic hormone) stimulation test (10 IU) to induce sustained secretion of cortisol, which was measured in serum samples from four koalas and subsequently it was attempted to locate a corresponding elevation in either cortisol or corticosterone measurements within the faeces. RESULTS: Although ACTH administration resulted in an elevation of serum cortisol for at least 4 h post injection, it was not possible to identify a corresponding peak in corticosterone or cortisol concentrations in extracts from the faeces, consistent with the known gut transit time of the koala. CONCLUSION: Faecal cortisol and corticosterone metabolites may not be reliable indices of acute changes in cortisol secretion in the koala and studies that attempt to use faecal cortisol as an index of stress will need to be interpreted with caution.

15.
Reprod Fertil Dev ; 24(7): 1008-18, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22935162

RESUMO

Electroejaculation (EEJ) has been used successfully to collect samples suitable for genome resource banking from a variety of endangered wildlife species. Ejaculates can also be used to evaluate the reproductive potential of individuals and provide information on seminal characteristics to aid in the development of sperm cryopreservation techniques. Electroejaculation techniques used for marsupial and eutherian species were tested on Tasmanian devils (n=35). Spermic ejaculates were collected in 54% (19/35) of EEJ attempts. Spermic ejaculates were low in volume (3.9±6.5×10(2) µL, range 10-3000 µL) and contained low numbers of spermatozoa (3.3±7.8×10(3) spermatozoa per ejaculate, range 6-33000). The osmolality and pH of presumptive urine-free ejaculates were 389±130 mOsm kg(-1) (range 102-566) and 7.0±0.9 (range 6.0-8.0), respectively. Prostatic bodies were observed in 79% (26/33) of ejaculates. Episodic fluctuations in serum testosterone concentrations were not detected during the EEJ procedure (P>0.05). Increases observed in serum cortisol concentrations during EEJ were less (P<0.05) than those observed after an adrenalcorticotropic hormone challenge and diurnal variation suggested that cortisol concentrations are greater during the day than at night (P<0.05). This information can be used to provide range values for the future examination of basic endocrine responses and the adrenal-pituitary axis of this species. This study also demonstrated that spermatozoa-rich devil electroejaculates are more difficult to obtain and poorer in quality than those of other marsupials.


Assuntos
Ejaculação , Espécies em Perigo de Extinção , Marsupiais/fisiologia , Recuperação Espermática/veterinária , Hormônio Adrenocorticotrópico/administração & dosagem , Animais , Ritmo Circadiano , Estimulação Elétrica , Hidrocortisona/sangue , Concentração de Íons de Hidrogênio , Injeções Intramusculares , Masculino , Marsupiais/sangue , Concentração Osmolar , Próstata/diagnóstico por imagem , Análise do Sêmen/veterinária , Contagem de Espermatozoides/veterinária , Motilidade dos Espermatozoides , Testosterona/sangue , Ultrassonografia
16.
Reprod Fertil Dev ; 24(7): 999-1007, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22935161

RESUMO

Devil facial tumour disease (DFTD) is the cause of the rapid decline of wild Tasmanian devils. Female devils are seasonal breeders with births peaking during autumn (i.e. March) but the degree of reproductive seasonality in male devils is unknown. The objective of this study was to examine the potential effects of season and DFTD on reproductive function in male devils (n=55). Testicular (1.90±0.23 g) and epididymal (0.90±0.06 g) weights were maximal during autumn and spring (P<0.05), whereas prostate (3.71±0.74 g) and Cowper's gland (0.68±0.22; 0.52±0.21 g) weights peaked during autumn (P<0.001). The motility of spermatozoa from the cauda epididymides extracted post-mortem was similar (P>0.05) across season and disease state (31.5±13.1% total motility). Testicular and epididymal weights were no different between animals displaying late or early-stage DTFD signs or disease-free animals (P>0.1). The accessory sex glands were larger in late-stage DFTD animals than in animals with early-stage disease signs or which were disease-free (P<0.01) but effects of season on this result can't be excluded. Serum testosterone concentrations peaked during summer (0.25±0.18 ng mL(-1)) but values were not different from the preceding and subsequent seasons (P>0.05), nor influenced by disease stage (P>0.1). Seasonal and DFTD-related changes in serum cortisol concentrations were not evident (P>0.1). Male devil reproduction does not appear to be restricted by season nor inhibited by DFTD.


Assuntos
Neoplasias Faciais/veterinária , Marsupiais/fisiologia , Reprodução , Estações do Ano , Animais , Glândulas Bulbouretrais/crescimento & desenvolvimento , Progressão da Doença , Epididimo/crescimento & desenvolvimento , Neoplasias Faciais/sangue , Neoplasias Faciais/fisiopatologia , Feminino , Hidrocortisona/sangue , Masculino , Marsupiais/sangue , Marsupiais/crescimento & desenvolvimento , Tamanho do Órgão , Próstata/crescimento & desenvolvimento , Motilidade dos Espermatozoides , Espermatogênese , Testículo/crescimento & desenvolvimento , Testosterona/sangue
17.
Theriogenology ; 78(2): 315-25, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22444554

RESUMO

Effective sperm cryopreservation protocols are limited to a small number of marsupial species. In this study, postmortem gamete rescue (PMGR) epididymal sperm samples from Tasmanian devils (N=34) euthanized due to the fatal Devil Facial Tumor Disease were used to develop long-term sperm storage techniques for the species. Cryoprotectant toxicity associated with equilibration of sperm samples in a TEST yolk diluent (TEST; 189 mM N-Tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, 85 mM Trizma base [Tris], 11 mM glucose, 20% vol/vol egg yolk; pH 7.1, and 315.0±5.0 mOsm/kg) with a final concentration of 0.06 M trehalose, or 4%, 10%, and 18% vol/vol of either glycerol or dimethyl sulfoxide (DMSO), was examined over 12 h at 15 °C. Trehalose supplementation resulted in an immediate decline (P<0.05) of total motility. After 12 h, total motility was reduced (P<0.05) in treatments containing 18% glycerol, and 10% and 18% dimethyl sulfoxide. The effects of final glycerol concentration (4% and 10%), glycerol equilibration duration (10 min 1 h, or 3 h) prefreeze, freezing rate and the addition of 0.10 M lactose or a combination of 0.10 M lactose and 0.11 M raffinose were assessed during three experiments on the cryopreservation of postmortem gamete rescue samples in TEST. In all experiments, motility and viability were reduced (P<0.01 postthaw). Samples cryopreserved in TEST supplemented with lactose or lactose with raffinose using a fast freezing rate (-8 °C/min from 4 to -40 °C, then -65 °C/min until -165 °C) produced the highest (P<0.05) postthaw motility (18.6±5.5% and 16.9±8.5%, respectively), which represented 35% to 48% retention of prefreeze motility. These results apparently were the best postthaw results of dasyurid sperm reported to date and will help lay the foundations for developing assisted reproductive technologies for marsupial species.


Assuntos
Criopreservação/veterinária , Epididimo/fisiologia , Marsupiais/fisiologia , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Conservação dos Recursos Naturais/métodos , Criopreservação/métodos , Crioprotetores/farmacologia , Masculino , Preservação do Sêmen/métodos , Especificidade da Espécie , Motilidade dos Espermatozoides
18.
Gen Comp Endocrinol ; 176(2): 182-91, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22306283

RESUMO

Numbers of wild Tasmanian devils are declining as a result of the fatal, transmissible Devil Facial Tumor Disease. A captive insurance population program has been initiated but current captive breeding rates are sub-optimal and therefore the goal of this project was to increase our understanding of the estrous cycle of the devil and elucidate potential causes of failed male-female pairings. Temporal patterns of fecal progestagen and corticosterone metabolite concentrations were examined for females (n=41) in three categories of reproductive status (successful: viable young, n=20 estrous cycles; unsuccessful: paired with a male but no young confirmed, n=44 estrous cycles; non-mated: no access to a male during estrus, n=8 estrous cycles) but substantial differences were not found. Females were more likely to produce pouch young if pairing with the male extended into late proestrus (P<0.05), thereby decreasing the time between pairing and presumed ovulation. The interval between the end of proestrous elevation in progestagen metabolite concentrations and the beginning of the luteal phase was 7.6±2.3 days in successful females. The length of the luteal phase in successful females was 12.5±1.4 days which was not different from unsuccessful or non-mated females (P>0.05). Unsuccessful females had 1-3 estrous cycles within a single year. Successful females were predominantly wild-caught (17/19, 90%) and most produced young following the first estrous cycle of the season (18/20, 90%). Unsuccessful females were predominantly captive born (20/27, 74%) in this study. It is possible that a proportion of females that do not produce pouch young achieve conception but the timing of reproductive failure continues to be elusive in this species.


Assuntos
Marsupiais/fisiologia , Reprodução/fisiologia , Animais , Ciclo Estral/fisiologia , Feminino , Masculino
19.
Zoo Biol ; 31(3): 275-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21404327

RESUMO

The Vancouver Island marmot (Marmota vancouverensis; VIM) is one of North America's most endangered species with fewer than 150 individuals remaining in the wild. A captive breeding program was established across four facilities in Canada as an insurance population and source of animals for reintroduction to the wild. The purpose of this study was to gather information about the basic reproductive biology and behavior of this species, which is essential to improve captive breeding programs. Regular fecal samples were obtained from adult female (n = 14) and male (n = 10) marmots, 2 years of age and older, over 1-3 breeding seasons (2-3 months duration posthibernation) for steroid hormone analysis. Enzyme immunoassays were validated for quantifying fecal testosterone metabolite concentrations for males, and fecal estrogen and progesterone metabolite concentrations for females. Results indicated that fecal progesterone metabolite concentrations can be used to monitor ovulation and pregnancy. Behavioral monitoring through infrared video surveillance was conducted in four breeding pairs over a 2-year period (n = 7 behavioral profiles). Breeding behaviors correlated strongly with changes in reproductive endocrine profiles. A high frequency of play behavior or "wrestling" was observed in conjunction with breeding activity before an elevation in progesterone metabolite concentrations. Impending parturition was associated with increased aggression and exclusion of the male from the maternal nestbox as well as an increase in nesting activity. Observational data combined with hormonal analysis suggest that female VIMs are induced ovulators and that multiple breeding attempts may be required for ovulation and conception. Gestation appears to be approximately 34 days from peak breeding activity (32 days from estimated ovulation). Fecal testosterone concentrations suggest that testicular activity is seasonal with the reproductive activity occurring immediately posthibernation. Monitoring breeding behavior is a useful means of indicating estrus, conception and pregnancy, which can also be supported by the hormonal analysis of daily fecal samples of individual animals.


Assuntos
Comportamento Animal/fisiologia , Cruzamento/métodos , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Marmota/metabolismo , Agressão/fisiologia , Animais , Colúmbia Britânica , Estrogênios/análise , Fezes/química , Feminino , Técnicas Imunoenzimáticas , Funções Verossimilhança , Masculino , Marmota/fisiologia , Modelos Estatísticos , Comportamento de Nidação/fisiologia , Observação , Gravidez , Progesterona/análise , Testosterona/análise , Gravação em Vídeo
20.
Theriogenology ; 76(4): 705-14, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21652060

RESUMO

The Tasmanian devil is suffering from a severe population decline due to the fatal Devil Facial Tumour Disease (DFTD). The development of assisted reproductive technologies such as AI and long-term sperm storage could facilitate genetic management of captive insurance populations. The aim of this study was to characterise semen samples collected post-mortem, and to develop a suitable diluent for short-term preservation of devil sperm. Low numbers of sperm (1.33 ± 0.85 × 10(6) sperm per male) were extracted from the epididymides of 17 males. Devil sperm sample characteristics such as concentration and morphology were similar to other dasyurids. The most commonly observed morphological abnormalities were midpiece separation, tail curling, and tail twisting (on the axial plane). Changes in motility occurred throughout the regions of the epididymis with (mean ± SD) 29.4 ± 16.8, 46.8 ± 13.6 and 29.4 ± 18.1% of sperm exhibiting motility, and 88.9 ± 11.4, 32.0 ± 24.3 and 0.1 ± 0.2% of motile sperm exhibiting forward progressive motility in the cauda, corpus and caput, respectively. Sperm from the cauda and corpus epididymis maintained 31.7 ± 26.6 and 80.6 ± 85.9%, respectively, of initial motility after 12 h at 15 °C in a TEST yolk buffer diluent. These findings provided new information regarding devil sperm biology and short-term sperm storage; such information is necessary for future development of long-term sperm preservation methods in the Tasmanian devil.


Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Epididimo/fisiologia , Marsupiais/fisiologia , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Membrana Celular/fisiologia , Conservação dos Recursos Naturais/métodos , Criopreservação/métodos , Masculino , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/ultraestrutura
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