A Case-Controlled Comparison of Behavioural Arousal Levels in Urine Spraying and Latrining Cats.

It is often suggested that both latrining and spraying in the home are associated with increased stress in cats. However, the scientific evidence for this is weak. We therefore examined faecal cortisol metabolite (FCM) levels in subjects using a case-control design. Eleven spraying and 12 problematic latrining cats (assessed as healthy after detailed medical examinations on an initial population of 18 spraying and 23 latrining cats) were assessed along with behaviourally normal and similarly healthy control subjects from the same multi-cat (n = 3-9) households. Individual faecal samples were collected by owners from both "case" and "control" cats after observing them defecate in all but one pair in each group. A total of five samples per cat (typically taken on a weekly basis) were collected and submitted to extraction procedures prior to FCM analysis via an 11-oxoaetiocholanolone enzyme immunoassay (EIA). Participant cats, both "cases" (nine "sprayers" and eight "latriners") and controls, were also individually video recorded (together with the owner) for 5 min in a dedicated room. FCM levels were significantly higher in individuals ("sprayers" and their controls) from spraying households than from the latrining households ("latriners" and their controls), but there was no significant difference between cats from the same household. Within a video observation test, cats from spraying houses spent proportionally more time moving (as opposed to stationary), but again there was no difference between cats from the same house. These results indicate that households in which a cat exhibits urine spraying, are generally more aroused, but "sprayers" are not more aroused than their housemates. Accordingly, we suggest appropriate management needs to be applied to the whole household to help alleviate the potential stress of all the cats in the home, and not just the one expressing this through urinary spraying behaviour.

Maternal depression and offspring's cortisol concentrations in a Brazilian sample / Depressão materna e concentração de cortisol de recém-nascidos em uma amostra brasileira / La depresión materna y la concentración de cortisol del recién nacido en una muestra brasilieira

Postpartum depression (PPD) is believed to cause a variety of child developmental problems, including alterations of the hypothalamic-pituitary-adrenal (HPA) axis function. The association of maternal depression with children's salivary cortisol level was investigated in three different moments: at birth (N=58), at four (N=64) and 36-month (N=81) after delivery. Mothers were screened for PPD at four months and for depression at 36-months after delivery using Edinburgh Postnatal Depression Scale (EPDS). Through ANOVA analysis results revealed a marginal difference of moderate effect size on cortisol concentration with higher levels for newborns whose mothers would be later screened for PPD when compared with control group. Contrary to our hypothesis we did not find this difference at four and neither at 36-months. Assuming that infants of mothers at risk for depression are born with slightly higher cortisol baseline, this difference among groups could not be verified on subsequent analysis at four and 36-months.

Acredita-se que a depressão pós-parto (DPP) possa prejudicar diversos aspectos do desenvolvimento infantil, incluindo alterações das funções do eixo Hipotálamo-pituitária-adrenal (HPA). A associação entre depressão materna e nível de cortisol salivar dos filhos foi investigada em três amostras brasileiras diferentes: ao nascimento (N=58), aos quatro (N=64) e 36 meses (N=81) após o parto. Mães preencheram a Escala de Depressão Pós-parto de Edinburgh aos 4 e 36 meses após o parto. Por meio da ANOVA resultados indicaram diferença marginal com tamanho de efeito moderado na concentração de cortisol com maiores concentrações em recém-nascidos cujas mães desenvolveram depressão pós-parto em comparação ao grupo controle. Contrariando nossa hipótese, esta diferença no nível de cortisol basal não foi encontrada aos quatro e aos 36 meses. Admitindo que os filhos de mães com sinais de DPP nascem com níveis basais de cortisol ligeiramente mais altos, esta diferença não foi verificada em momentos posteriores.

Se cree que la depresión post-parto (DPP) causa una variedad de problemas del desarrollo, incluyendo alteraciones funcionales en el eje hypotálamo-hipofisario-adrenal (HHA). Nuestro objetivo era el investigar la posible asociación entre niveles de cortisol salivar en hijos y depresión materna en tres momentos distintos: 2 días después del parto (N=58), cuatro meses después (N=64) y 36 meses después (N=81). Las madres completaron la Escala de Depresión Postparto de Edimburgo a las 4 y 36 meses después del parto. Un test de ANOVA mostró diferencias marginales de efecto moderado en los niveles de cortisol en hijos de madres con DPP comparados con grupo de control. Suponiendo que los hijos de madres con DPP tienen niveles de cortisol ligeramente elevados al nacer, no se observaron estas diferencias en otros momentos.

Comparison of two methods for glucocorticoid evaluation in maned wolves / Comparação de dois métodos para avaliação de glicocorticóides em lobos guarás

Analysis of faecal glucocorticoid metabolites provides a powerful noninvasive tool for monitoring adrenocortical activity in wild animals. However, differences regarding the metabolism and excretion of these substances make a validation for each species and sex investigated obligatory. Although maned wolves (Chrysocyon brachyurus) are the biggest canids in South America, their behaviour and physiology are poorly known and they are at risk in the wild. Two methods for measuring glucocorticoid metabolites in maned wolves were validated: a radio- and an enzyme immunoassay. An ACTH challenge was used to demonstrate that changes in adrenal function are reflected in faecal glucocorticoid metabolites. Our results suggest that both methods enable a reliable assessment of stress hormones in maned wolves avoiding short-term rises in glucocorticoid concentrations due to handling and restraint. These methods can be used as a valuable tool in studies of stress and conservation in this wild species.

A análise de metabólitos de glicocorticóides fecais é uma ferramenta não-invasiva poderosa para o monitoramento da atividade adrenal em animais silvestres. Entretanto, diferenças no metabolismo e na excreção dessas substâncias tornam obrigatória a validação desse método para cada espécie e sexo investigado. Embora os lobos guarás (Chrysocyon brachyurus) sejam os maiores canídeos da América do Sul, seu comportamento e fiisiologia são ainda pouco conhecidos e estes animais são ameaçados. Dois métodos para mensuração de metabólitos de glicocorticóides em lobos guarás foram validados: um radio- e um enzima- imuno-ensaio. Um desafiio de ACTH foi usado para demonstrar que alterações no funcionamento adrenal podem ser detectadas nas concentrações metabólitos de glicocorticóides fecais. Nossos resultados sugerem que ambos os métodos possibilitam uma avaliação confiiável dos hormônios relacionados ao estresse em lobos guarás, evitando assim aumentos de curta duração nas concentrações glicocorticóides, devidos ao manejo e contenção. Esses métodos podem ser usados como uma ferramenta valiosa em estudos de estresse e conservação com essa espécie silvestre.

Comparison of two methods for glucocorticoid evaluation in maned wolves / Comparação de dois métodos para avaliação de glicocorticóides em lobos guarás

Analysis of faecal glucocorticoid metabolites provides a powerful noninvasive tool for monitoring adrenocortical activity in wild animals. However, differences regarding the metabolism and excretion of these substances make a validation for each species and sex investigated obligatory. Although maned wolves (Chrysocyon brachyurus) are the biggest canids in South America, their behaviour and physiology are poorly known and they are at risk in the wild. Two methods for measuring glucocorticoid metabolites in maned wolves were validated: a radio- and an enzyme immunoassay. An ACTH challenge was used to demonstrate that changes in adrenal function are reflected in faecal glucocorticoid metabolites. Our results suggest that both methods enable a reliable assessment of stress hormones in maned wolves avoiding short-term rises in glucocorticoid concentrations due to handling and restraint. These methods can be used as a valuable tool in studies of stress and conservation in this wild species.(AU)

A análise de metabólitos de glicocorticóides fecais é uma ferramenta não-invasiva poderosa para o monitoramento da atividade adrenal em animais silvestres. Entretanto, diferenças no metabolismo e na excreção dessas substâncias tornam obrigatória a validação desse método para cada espécie e sexo investigado. Embora os lobos guarás (Chrysocyon brachyurus) sejam os maiores canídeos da América do Sul, seu comportamento e fiisiologia são ainda pouco conhecidos e estes animais são ameaçados. Dois métodos para mensuração de metabólitos de glicocorticóides em lobos guarás foram validados: um radio- e um enzima- imuno-ensaio. Um desafiio de ACTH foi usado para demonstrar que alterações no funcionamento adrenal podem ser detectadas nas concentrações metabólitos de glicocorticóides fecais. Nossos resultados sugerem que ambos os métodos possibilitam uma avaliação confiiável dos hormônios relacionados ao estresse em lobos guarás, evitando assim aumentos de curta duração nas concentrações glicocorticóides, devidos ao manejo e contenção. Esses métodos podem ser usados como uma ferramenta valiosa em estudos de estresse e conservação com essa espécie silvestre.(AU)

Social stress and reproductive success in the female Syrian hamster: endocrine and behavioral correlates.

In many mammal species, reproduction is not shared equally among the members of a social unit. Even though reproductive skew seems unlikely in females of solitary species, this phenomenon could result from environmental factors. Although solitary in the wild, captive Syrian hamsters (Mesocricetus auratus) are generally housed in groups. We investigated whether social stress produces some degree of reproductive skew in this solitary species and whether female reproductive success varies as a function of social rank. To assess the physiological relationship between social stress and fertility, we monitored reproductive hormones and glucocorticoids of solitary and pair-housed females during pregnancy by means of recently established non-invasive methods for measuring hormone metabolites in the feces. The patterns of fecal progesterone, estrogen and glucocorticoid metabolites were similar to those found in blood and reported in the literature for pregnant hamsters. As expected, dominant females had higher breeding success than subordinate females. However the rate of reproductive failure was also very high among the singly housed females of our control group. The number of pups per litter, the average sex-ratio in each group, and the mean weight of pups did not differ significantly among groups. Glucocorticoid concentrations were unaffected by housing and social rank and the few differences between the endocrine profiles of singly- and pair-housed females are not sufficient to explain the observed difference in breeding success. It is likely that social isolation impairs reproduction in the same manner as subordination. Our findings suggest that social isolation of animals accustomed to group living was equally as disturbing as cohabitation with an unknown conspecific.

Validação de um radioimunoensaio para a quantificação de metabólitos fecais de testosterona em hamster Sírio (Mesocricetus auratus) / Validation of a radioimmunoassay for the quantification of fecal testosterone metabolites in the Syrian hamster (Mesocricetus auratus)

Modelo para o estudo de diversas doenças humanas, o hamster tem sido objeto de numerosos estudos comportamentais e envolvendo estresse e/ou comportamento agonístico que supõem, muitas vezes, o monitoramento das flutuações hormonais nos indivíduos envolvidos. O objetivo do presente trabalho foi confirmar a adequação de um conjunto comercial para dosagem de testosterona em sangue humano para a quantificação de metabólitos fecais de testosterona (MFT) em hamsters Sírios machos e fêmeas. Dez machos foram submetidos a um desafio com um agonista de GnRH para estimular a atividade testicular, elevando os níveis circulantes de testosterona. Cinco fêmeas receberam uma injeção de testosterona enquanto cinco outras receberam uma injeção de solução salina. Amostras de fezes coletadas antes e depois dos procedimentos, assim como amostras fecais de 20 fêmeas gestantes coletadas ao longo da gestação foram analisadas com um conjunto comercial para radioimunoensaio. Um pico de MFT 12h após a injeção seguido de uma queda abaixo do nível basal comprovou que, nos machos, as alterações nos níveis de MFT refletem as alterações da concentração de testosterona no sangue. Nestes observou-se um ciclo circadiano das concentrações de MFT com acrofase no início do período claro correspondendo ao ciclo descrito para as concentrações sanguíneas na literatura. Nas fêmeas a administração de testosterona exógena provocou uma elevação importante dos níveis de MFT, mas as concentrações medidas ao longo da gestação não refletiram o padrão dos níveis sanguíneos do hormônio endógeno. O conjunto para radioimunoensaio para testosterona em sangue humano mostrou-se adequado para o monitoramento da função testicular no hamster macho, mas um ensaio mais específico seria necessário para as fêmeas.

Besides being models for a variety of human diseases, hamsters have been object of numerous behavioral studies about stress and agonistic behavior. Such studies usually involve hormone change monitoring. The aim of the present study was to confirm the suitability of a commercial kit for human serum testosterone analysis to quantify testosterone metabolites in the feces (MFT) of male and female Syrian hamsters. Ten males were submitted to a GnRH challenge test to stimulate testicular activity and increase circulating testosterone levels. Five females received a testosterone injection and five other females were given a saline injection. Fecal samples collected before and after the procedures, and fecal samples collected from 20 pregnant females through gestation were analyzed for MFT with a commercial radioimmunoassay. The detection of a MFT peak 12 h after GnRH administration followed by a decrease under baseline showed that, in males, changes in the levels of MFT are related to respective changes of testosterone concentrations in the blood. Again in males a circadian cycle of MFT similar to the circadian rhythm described in literature for blood concentrations was detected. The administration of exogenous testosterone caused in females a dramatic peak of MFT. However, the concentrations measured through gestation did not reflect the pattern of endogenous testosterone blood levels as described in the literature. Therefore, the use of a radioimmunoassay for human blood testosterone was validated in male Syrian hamster, but a more specific assay would be necessary for female hamsters.

Validação de um radioimunoensaio para a quantificação de metabólitos fecais de testosterona em hamster Sírio (Mesocricetus auratus) / Validation of a radioimmunoassay for the quantification of fecal testosterone metabolites in the Syrian hamster (Mesocricetus auratus)

Modelo para o estudo de diversas doenças humanas, o hamster tem sido objeto de numerosos estudos comportamentais e envolvendo estresse e/ou comportamento agonístico que supõem, muitas vezes, o monitoramento das flutuações hormonais nos indivíduos envolvidos. O objetivo do presente trabalho foi confirmar a adequação de um conjunto comercial para dosagem de testosterona em sangue humano para a quantificação de metabólitos fecais de testosterona (MFT) em hamsters Sírios machos e fêmeas. Dez machos foram submetidos a um desafio com um agonista de GnRH para estimular a atividade testicular, elevando os níveis circulantes de testosterona. Cinco fêmeas receberam uma injeção de testosterona enquanto cinco outras receberam uma injeção de solução salina. Amostras de fezes coletadas antes e depois dos procedimentos, assim como amostras fecais de 20 fêmeas gestantes coletadas ao longo da gestação foram analisadas com um conjunto comercial para radioimunoensaio. Um pico de MFT 12h após a injeção seguido de uma queda abaixo do nível basal comprovou que, nos machos, as alterações nos níveis de MFT refletem as alterações da concentração de testosterona no sangue. Nestes observou-se um ciclo circadiano das concentrações de MFT com acrofase no início do período claro correspondendo ao ciclo descrito para as concentrações sanguíneas na literatura. Nas fêmeas a administração de testosterona exógena provocou uma elevação importante dos níveis de MFT, mas as concentrações medidas ao longo da gestação não refletiram o padrão dos níveis sanguíneos do hormônio endógeno. O conjunto para radioimunoensaio para testosterona em sangue humano mostrou-se adequado para o monitoramento da função testicular no hamster macho, mas um ensaio mais específico seria necessário para as fêmeas.(AU)

Besides being models for a variety of human diseases, hamsters have been object of numerous behavioral studies about stress and agonistic behavior. Such studies usually involve hormone change monitoring. The aim of the present study was to confirm the suitability of a commercial kit for human serum testosterone analysis to quantify testosterone metabolites in the feces (MFT) of male and female Syrian hamsters. Ten males were submitted to a GnRH challenge test to stimulate testicular activity and increase circulating testosterone levels. Five females received a testosterone injection and five other females were given a saline injection. Fecal samples collected before and after the procedures, and fecal samples collected from 20 pregnant females through gestation were analyzed for MFT with a commercial radioimmunoassay. The detection of a MFT peak 12 h after GnRH administration followed by a decrease under baseline showed that, in males, changes in the levels of MFT are related to respective changes of testosterone concentrations in the blood. Again in males a circadian cycle of MFT similar to the circadian rhythm described in literature for blood concentrations was detected. The administration of exogenous testosterone caused in females a dramatic peak of MFT. However, the concentrations measured through gestation did not reflect the pattern of endogenous testosterone blood levels as described in the literature. Therefore, the use of a radioimmunoassay for human blood testosterone was validated in male Syrian hamster, but a more specific assay would be necessary for female hamsters.(AU)

Sex differences in the excretion of fecal glucocorticoid metabolites in the Syrian hamster.

We verified the relevance of measuring fecal glucocorticoid metabolites (FGM) to assess the stress response of the Syrian hamster. Male and female hamsters (n = 10 each) were submitted to an adrenocorticotropic hormone (ACTH) challenge test, whereas animals in the control group received 0.5 mL of sterile isotonic saline solution. All feces voided by each animal were collected at 4 h intervals from 24 h before (baseline) until 48 h after injections. FGM were quantified using an 11-oxoetiocholanolone enzyme immunoassay (EIA). Basal concentrations of FGM were almost four times higher in males than in females. Following ACTH administration, FGM levels started rising from 8 h onwards, reaching peak concentrations 20 or 28 h post injection in males and females, respectively. Despite the much higher absolute concentrations present in males, the relative increase (500%) in response to the ACTH stimulation was similar in both sexes. Sex differences in FGM levels are in accordance with results reported by others regarding the hamster adrenal physiology. The comparison of the adrenocortical response of males and females to an ACTH challenge provided new information about the amplitude and the timing of such a response and the excretion of glucocorticoids in both sexes. We demonstrated for the first time in the Syrian hamster that adrenocortical activity can be monitored in fecal samples in a noninvasive way. Our study provides a humane, practical, and noninvasive alternative to blood removal and therefore a powerful tool for stress-related studies in a species frequently used as an animal model in medical research.

Validação laboratorial e fisiológica de conjunto comercial para a quantificação de corticóides fecais em chimpanzé (Pan troglodytes) e orangotango (Pongo pygmaeus), cativos e submetidos a enriquecimentos ambientais / Laboratorial and physiological validation of comercial kits for quantification of fecal corticoids of captive chimpanzees (Pan troglodytes) and orangutangs (Pongo pygmaeus) under environmental enriched conditions

Neste trabalho foi realizado estudo comparativo dos níveis decorticóides fecais (CF) de chimpanzé (Pan troglodytes) e orangotango(Pongo pygmaeus). Foram analisadas amostras coletadas em duas fasesdistintas, relacionadas com a introdução de técnicas de enriquecimentoambiental, a saber: Base (antes da introdução) e Habituação(imediatamente após). Realizamos as validações do conjunto comercialpara radioimunoensaio ImmunuChem™ Double AntibodyCorticosterone da MP Biomedicals, para mensuração de CF. A validaçãolaboratorial dos conjuntos diagnósticos para uso em extrato fecal deprimatas foi realizada pelo método de paralelismo, no qual, para cadaespécie, concentrações conhecidas de corticosterona foram adicionadasa um pool de extratos fecais, sendo estas amostras analisadas emseguida. As inclinações das curvas obtidas nestes ensaios e da curvapadrão do ensaio foram então comparadas. Os resultados obtidospara chimpanzé e orangotango, foram respectivamente, Y=17,23+1,31*X;R

A comparative study of fecal corticoids (FC) concentrations was carriedout with chimpanzees (Pan troglodytes) e orangutans (Pongo pygmaeus).Fecal samples were collected before (Basal) and just after (Habituation)enrichment introduction and analyzed. We performed biochemical andphysiological validations of the ImmunuChem™ Double AntibodyCorticosterone kit for radioimmunoassay from MP Biomedicals forquantifying FC concentrations. To establish the biochemical validity ofour assay we performed parallelism assays in which pooled fecal extractsfrom both species were spiked with known quantities of corticosteronestandard and the slopes of the curves obtained with these samples andthe standard curves of the kits were compared. The correlation coefficientswere R

Assessment of the physiologic stress response by quantification of fecal corticosteroids.

Noninvasive techniques to monitor reproductive or stress hormones are now widely used in captive and free-ranging wildlife. These methods offer great advantages and deserve to be used also in laboratory rodents. However, we remain naïve about factors that may influence the accuracy of these techniques. The aim of this study was to evaluate the adequacy of measuring the concentration of cortisol fecal metabolites to assess the physiologic stress response. Ten adult female Syrian hamsters were ovariectomized, and all feces voided were collected daily for 4 d before and 5 d after surgery. Cortisol fecal metabolites were extracted and quantified by radioimmunoassay. We determined per-gram fecal cortisol metabolite concentrations, total 24-h fecal output and total 24-h fecal cortisol metabolite production. Surgery considerably affected fecal output, and using per-gram versus total cortisol metabolites led to different conclusions: whereas concentrations increased significantly just after ovariectomy and decreased on subsequent days, the total excreted cortisol metabolites varied in a symmetrical pattern. Therefore, the relative per-gram measure of hormones may not reflect the total amount of circulating hormones, because these measures are comparable only if the volume of the material in which the hormone is contained is the same in the 2 groups.