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1.
Appetite ; 198: 107372, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38657683

RESUMEN

Avid eating behaviours, including greater responsiveness to food cues and emotional over-eating, have been linked to child overweight and obesity. Parental feeding practices are modifiable components of a child's food environment and may be key levers for behaviour change in tailored interventions to support parents of children with avid eating behaviour. However, there is a lack of research examining parents' experiences in this context. This study aimed to explore parents' experiences of feeding children with avid eating behaviour and to understand any challenges experienced in this context. Semi-structured interviews with parents (N = 15) of a preschool child (3-5 years) identified as having an avid eating behaviour profile explored how children's avid eating manifests, the parental feeding practices used to manage avid eating, and the perceived effectiveness of these strategies. Data were analysed using reflexive thematic analysis. Four core themes were generated. Theme one, 'Have they got worms? Children's insatiable hunger', captures parents' interpretation of the complex ways in which avid eating behaviour manifests. Theme two, 'Parenthood as a duty', illustrates how parents' perceived responsibilities shape their feeding practices. Theme three, 'Lifelong habits', captures parents' use of responsive feeding practices to support children's healthy relationship with food. Theme four, 'Picking battles', captures the structure- and coercive-based feeding strategies commonly used to manage children's avid eating. This novel study provides an in-depth understanding of the complex ways that children's avid eating behaviour manifests, and the strategic and creative parental feeding practices used to manage these behaviours. Such findings are valuable for informing the development of future support resources for parents/caregivers to help their children with avid eating behaviours to develop a healthy relationship with food.


Asunto(s)
Conducta Alimentaria , Responsabilidad Parental , Padres , Humanos , Preescolar , Femenino , Masculino , Padres/psicología , Conducta Alimentaria/psicología , Responsabilidad Parental/psicología , Conducta Infantil/psicología , Relaciones Padres-Hijo , Obesidad Infantil/psicología , Adulto , Hambre , Investigación Cualitativa , Señales (Psicología) , Hiperfagia/psicología
2.
Am J Primatol ; 85(3): e23457, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36537335

RESUMEN

Although biomarkers are often used for predicting morbidity and mortality in humans, similar data are lacking in our closest relatives. This study analyzed 16 biomarkers in zoo-housed chimpanzees and bonobos from serum samples collected during both routine and nonroutine veterinary immobilizations. Generalized linear and generalized linear mixed models were used to determine the efficacy of each biomarker to predict all-cause morbidity, defined as the presence of at least one chronic condition, or cardiac disease as a subset of all-cause morbidity. Cox proportional hazards models were used to examine associations between biomarkers and mortality risk from any cause. Analyses were conducted using two data sets for each species, one with all values retained (chimpanzees: n = 148; bonobos: n = 33) and the other from samples collected during routine immobilizations only (chimpanzees: n = 95; bonobos: n = 23). Consistent results across both data sets in chimpanzees included associations of higher cortisol with all-cause morbidity risk, lower creatinine with cardiac disease risk, and higher creatinine with mortality risk, and in bonobos were increased cardiac disease risk with higher cortisol and lower dehydroepiandrosterone-sulfate, fructosamine, and triglycerides. However, there were some inconsistencies between data sets, such as tumor necrosis factor-α predicting mortality risk positively in chimpanzees when all values were retained, but negatively for routine values only. Despite the close evolutionary relationships between chimpanzees and bonobos, the only result observed in both species was a negative association between albumin and mortality risk in the all values retained data sets. Thus, data suggest some biomarkers may be useful predictors of future health outcomes, although a better understanding of both individual and species variation in biomarkers and their contribution to health risks is needed.


Asunto(s)
Hominidae , Pan troglodytes , Humanos , Animales , Pan paniscus , Conducta Social , Creatinina , Hidrocortisona , Biomarcadores
3.
J Zoo Wildl Med ; 53(4): 696-704, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36640071

RESUMEN

Amyloidosis is frequently identified during postmortem examination of captive eastern bongo (Tragelaphus eurycerus isaaci) in the European Endangered Species Programme (EEP). However, its significance and etiopathogenesis are poorly understood. The objective of this study was to investigate the prevalence of amyloidosis within this population and identify potential predictive factors for the presence of disease. Postmortem reports obtained from 24 EEP institutions were analyzed and assessed for evidence of amyloidosis. Seventy-two individuals had histopathological assessment performed after gross postmortem examination and were included in the study. Further histopathological analysis was performed on Congo red-stained slides from 26 individuals, and organ predilection sites were identified. Immunohistochemical analysis was performed in six individuals to identify the type of amyloid present. Serum amyloid A (SAA) analysis was performed on blood samples from 34 individuals, and concentrations in affected and unaffected individuals were compared. Amyloidosis was reported in 26 animals (36%). The association between the presence of amyloidosis and sex, age, or body condition was not statistically significant. However, amyloidosis was not identified in any individuals under the age of 6 yr. The presence of chronic inflammatory conditions was the only statistically significant predictive factor for the presence of amyloidosis (P = 0.03). Chronic inflammatory conditions present included nephritis, enteritis, and pneumonia. The majority of affected animals presented with amyloid deposition in multiple organs, with the liver and kidneys being most commonly affected. Immunohistochemistry confirmed the presence of AA amyloid. The association between the presence of amyloidosis and SAA values measured on a single occasion was not statistically significant. This study identified a high prevalence of amyloidosis within the captive European eastern bongo population associated with chronic inflammatory conditions. Antemortem diagnosis of amyloidosis remains challenging, and this study indicates that SAA protein concentrations are not a reliable indicator for the presence of amyloidosis.


Asunto(s)
Amiloidosis , Proteína Amiloide A Sérica , Animales , Proteína Amiloide A Sérica/metabolismo , Prevalencia , Riñón/metabolismo , Amiloidosis/epidemiología , Amiloidosis/veterinaria
4.
J Zoo Wildl Med ; 53(4): 801-810, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36640083

RESUMEN

Osteoarthritis (OA) is common in zoo Asian (Elephas maximus) and African (Loxodonta africana) elephants. This study investigated the relationship between confirmed or suspected OA with ovarian cyclicity, gonadotropins, progestagens, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and collagen type I (CTX-I) in zoo elephants. In Asian elephants, odds of having confirmed or suspected OA decreased with cycling (OR = 0.22, P = 0.016; OR = 0.29, P = 0.020, respectively), however, not when adjusted for age (odds ratio [OR] = 0.31, P = 0.112; OR = 0.58, P = 0.369, respectively). In African elephants, none of the models between confirmed OA and cycling status were significant (P > 0.060), while the odds of having suspected OA decreased with cycling (OR = 0.12, P = 0.001), even after adjusting for age (OR = 0.15, P = 0.005). Progestagens (Asian elephants P > 0.096; African elephants P > 0.415), LH (Asian P > 0.129; African P > 0.359), and FSH (Asian P > 0.738; African P > 0.231) did not differ with confirmed or suspected OA status, unadjusted. CTX-I concentrations were not related to OA status (P > 0.655). This study concluded hormonal changes may not have a strong impact on OA, so additional investigation into other serologic biomarkers is warranted.


Asunto(s)
Elefantes , Osteoartritis , Animales , Progestinas , Hormona Luteinizante , Hormona Folículo Estimulante , Osteoartritis/veterinaria , Animales de Zoológico
5.
Appetite ; 168: 105779, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34756937

RESUMEN

Research has shown that seeing positive facial expressions (FEs) towards food increased children's desire to eat foods rated as disliked. However, the effect of adults' positive FEs whilst eating a raw vegetable on children's acceptance and intake of nutritious foods that are less preferred (e.g., vegetables) remains to be established. This study aimed to examine the effect of models' FEs eating raw broccoli on children's acceptance and intake of raw broccoli. 111 children aged 4-6 years (64 male, 47 female) were randomised to watch a video of unfamiliar adult models eating raw broccoli with a positive or neutral facial expression (FE), or a non-food control video. Children's acceptance and intake of raw broccoli was assessed. Data about parent and child characteristics was provided by parents. There was a main effect of FE type on children's frequency of tastes (p = .03) and intake of broccoli (p = .02). Children who were exposed to models eating broccoli with positive FEs had greater frequency of tastes (p = .04) and intake of broccoli (p = .03), than children in the control condition, but not compared to children in the neutral FE condition (p > .05). There was no effect of positive FEs on children's willingness to try broccoli (p > .05). These findings suggest that observing others enjoy a commonly disliked vegetable can encourage children's tastes and intake of the vegetable. Thus, exposing children to others enjoying vegetables could be a useful strategy for encouraging healthier eating in children. Further work is needed to determine whether a single exposure is sufficient and whether these effects are sustained over time.


Asunto(s)
Expresión Facial , Verduras , Adulto , Niño , Ingestión de Alimentos , Conducta Alimentaria , Preferencias Alimentarias , Humanos , Padres , Gusto
6.
Proc Biol Sci ; 288(1957): 20210552, 2021 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-34403636

RESUMEN

Interactions between hosts and their resident microbial communities are a fundamental component of fitness for both agents. Though recent research has highlighted the importance of interactions between animals and their bacterial communities, comparative evidence for fungi is lacking, especially in natural populations. Using data from 49 species, we present novel evidence of strong covariation between fungal and bacterial communities across the host phylogeny, indicative of recruitment by hosts for specific suites of microbes. Using co-occurrence networks, we demonstrate marked variation across host taxonomy in patterns of covariation between bacterial and fungal abundances. Host phylogeny drives differences in the overall richness of bacterial and fungal communities, but the effect of diet on richness was only evident in the mammalian gut microbiome. Sample type, tissue storage and DNA extraction method also affected bacterial and fungal community composition, and future studies would benefit from standardized approaches to sample processing. Collectively these data indicate fungal microbiomes may play a key role in host fitness and suggest an urgent need to study multiple agents of the animal microbiome to accurately determine the strength and ecological significance of host-microbe interactions.


Asunto(s)
Microbiota , Micobioma , Animales , Bacterias/genética , Interacciones Microbiota-Huesped , Filogenia
7.
Reprod Fertil Dev ; 33(18): 841-854, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34844663

RESUMEN

With fewer than 7500 cheetahs remaining in the wild, ex situ cheetah populations serve as an insurance policy against extinction and a resource to study species' biology. This study aimed to identify the age of pubertal onset in ex situ female cheetahs using non-invasive faecal steroid hormone monitoring and body weights. Faecal samples from nine female cheetahs were collected two to three times weekly from 2 to 36months of age and body weights were recorded every 3months. Faecal oestrogen metabolites (FOM) and faecal glucocorticoid metabolites (FGM) were analysed using enzyme immunoassays and samples were categorised into 6-month intervals to compare endocrine characteristics. Faecal hormone and body weight data were analysed using generalised linear mixed models. Age was a significant predictor of mean and baseline FOM concentrations, number of FOM peaks, mean and maximum FOM peak concentrations and the number of cycles. Female cheetahs aged 24-30months exhibited a marked rise in mean FOM concentration and the number of FOM peaks and cycles increased with age until 24-30months. Females attained adult body weight by 21months of age. Mean and baseline FGM concentrations were highest at the 0-6 and 12-18months of age groups and did not follow the same FOM patterns. Based on body weight data, the FOM concentrations and peak patterning, females were considered pubertal from 24 to 30months of age. Characterisation of cheetah puberty has direct and significant implications for the improvement of management and reproductive success of cheetahs under human care. This information is particularly informative for identifying important windows of development, littermate dispersal and breeding introductions.


Asunto(s)
Peso Corporal/fisiología , Estrógenos/metabolismo , Heces/química , Glucocorticoides/análisis , Maduración Sexual/fisiología , Acinonyx , Animales , Estrógenos/análisis , Femenino
8.
Gen Comp Endocrinol ; 289: 113376, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31881202

RESUMEN

To achieve self-sustaining and genetically diverse populations ex situ, captive breeding programmes must ensure good overall rates of reproduction, and equal contribution across individuals. Previous research in the critically endangered eastern black rhinoceros (Diceros bicornis michaeli) revealed a high incidence of irregular oestrous cyclicity; in particular extended cycle duration among nulliparous females and acyclic periods in parous females that have not bred for several years. Irregular ovarian activity could play a role in reduced reproductive output; however, the mechanisms underlying these anomalies are poorly understood. The aim of this study was to measure faecal glucocorticoid metabolite (fGCM) concentrations and variability prior to and during periods of regular and irregular ovarian activity, and determine if adrenal activity influences the occurrence of different cycle types in this species. Faecal samples were collected every other day from parous (N = 6) and nulliparous (N = 12) females at eight European institutions for periods of 9-15 months. Concentration and variability in fGCM were compared between periods of regular and irregular cyclicity and between different cycle types (<20 days, 20-40 days, >40 days, acyclic) using generalized linear mixed models. Concentrations of fGCM were influenced by season and higher during the luteal than the follicular phase of the oestrous cycle. Taking this into account, fGCMs were increased during periods of irregular cyclicity (all types combined and during cycles >40 days in length) compared to 20-40 day cycles. This was predominantly driven by nulliparous females. The variation in fGCM concentration also differed between periods of regular and irregular cyclicity; higher standard deviation in fGCM preceded irregular cycles and >40 day cycles compared to 20-40 day cycles. These results suggest that although fGCM concentrations fluctuate across the oestrous cycle in this species, changes in adrenal activity at specific times could be one factor associated with irregular ovarian activity in the black rhinoceros.


Asunto(s)
Ciclo Estral/fisiología , Ovario/metabolismo , Animales , Femenino , Perisodáctilos , Reproducción
9.
Zoo Biol ; 39(4): 217-229, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32506680

RESUMEN

The impact of visitors on the well-being of captive animals presents both positive and potentially negative consequences. While some amount of novelty through visitor stimulation offers the opportunity for a more complex captive environment, anecdotal evidence from primate staff observations at the Smithsonian's National Zoo and Conservation Biology Institute suggested that gorillas exhibited increased restlessness during the annual month-long late night ZooLights (ZL) event than before it. The current study compared activity budgets, aggression (interactions involving contact between conspecifics and displays toward visitors), and abnormal behaviors in two groups of socially housed gorillas for 1-month periods before, during, and after the 2015 ZL event. We also compared the fecal glucocorticoid metabolite profiles of all six gorillas across these same observation periods. Physiologically, most individuals appeared to cope appropriately with the increased visitor presence during the event. We saw little difference in contact aggression; however, abnormal behavior was observed in some gorillas during and after the event, which highlights the importance of individual analysis and data interpretation. As predicted, we found that the majority of gorillas rested less during ZL than during other observation periods, particularly adult females in the mixed sex troop. Preliminary results of this study aided the decision of zoo management to close initially the Great Ape House and subsequently most animal buildings during future ZL events to avoid the potential disruption of normal activity patterns. While the findings of this study were mixed as to the impact of the event on these gorillas, the results suggest that zoos should carefully consider the possible ramifications of keeping great ape buildings open for lengthy multi-night events.


Asunto(s)
Bienestar del Animal , Animales de Zoológico , Conducta Animal , Gorilla gorilla/fisiología , Animales , Femenino , Gorilla gorilla/psicología , Masculino , Conducta Social , Estrés Psicológico
10.
Gen Comp Endocrinol ; 276: 1-13, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-30735672

RESUMEN

Longitudinal analyses of serum testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin, glucose, insulin, triglycerides, cholesterol, total and free thyroxine (T4), total triiodothyronine (T3), thyroid stimulating hormone (TSH), and cortisol were conducted to investigate pituitary, metabolic, and adrenal changes related to testicular function and musth status in zoo-housed elephant bulls. Blood samples were collected twice a month for 12 months from 14 African and 12 Asian bulls at 17 facilities in North America. Building on previous studies, our results show that musth is associated with increased testosterone, LH, FSH, and cortisol secretion, and a decrease in thyroid hormone (total and free T4) production. In addition, glucose and triglycerides were higher during musth than non-musth periods, indicative of altered sugar and fat metabolism. There were significant differences associated with age for LH, FSH and testosterone, all increasing, whereas the glucose-to-insulin ratio (G:I) decreased with age. A species comparison found African and Asian elephants differed in measures of insulin, prolactin, cholesterol and the G:I. Across all hormones, high inter-individual variability was observed, making it difficult to define a general musth endocrine profile or to assess musth status from single samples. These results highlight the need for facilities hosting bulls to closely and consistently monitor each individual from an early age and throughout musth and non-musth periods to determine the pattern for each male.


Asunto(s)
Glándulas Suprarrenales/metabolismo , Conducta Animal , Elefantes/metabolismo , Gónadas/metabolismo , Hormonas/metabolismo , Hipófisis/metabolismo , Glándula Tiroides/metabolismo , África , Agresión , Animales , Asia , Glucemia/metabolismo , Colesterol/sangre , Elefantes/sangre , Insulina/sangre , Modelos Lineales , Masculino , Triglicéridos/sangre
11.
Adv Exp Med Biol ; 1200: 91-162, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31471796

RESUMEN

To reverse the trend of declining wildlife populations globally, individuals must be provided with conditions that allow them to not just survive, but to thrive. It is no longer only the remit of captive breeding programs to ensure animal well-being; in situ conservation efforts also must consider how environmental and anthropogenic pressures impact wild populations, and how to mitigate them-especially with regards to reproduction and survival. Stress and welfare are complex concepts that necessitate an understanding of how stressors affect animals on both individual and population levels. There are species differences in how factors impact well-being, related in part to natural history, which also are shaped by individual perceptions and coping abilities. A multitude of stress-related responses then have the potential to disrupt fertility on many levels, and ultimately fitness. A major limitation to advancing welfare science is the lack of definitive tests to verify welfare status; i.e., is the animal happy or not? While analyses of circulating or excreted glucocorticoids have for decades been the primary method of assessing stress, today we recognize the need for more objective indicators that incorporate multiple physiological systems, including behavior, to assess both negative and positive welfare states. In this chapter, we discuss the potential for stress to disrupt, and sometimes facilitate reproduction, including the key role that glucocorticoids play. We then discuss a number of physiological biomarkers, which in addition to glucocorticoids, have the potential to assess well-being and the role of stress on reproduction. Finally, we discuss allostatic load, a method by which multiple physiological markers are used to inform on morbidity and mortality risk in humans, which if applied to wildlife, could be a powerful tool for conservation.


Asunto(s)
Alostasis , Animales Salvajes , Glucocorticoides/fisiología , Reproducción , Estrés Fisiológico , Animales , Biomarcadores , Conservación de los Recursos Naturales
12.
Gen Comp Endocrinol ; 268: 22-33, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30026021

RESUMEN

Cheetahs are one of the most heavily studied felid species, with numerous publications on health, disease, and reproductive physiology produced over the last 30 years. Despite this relatively long history of research, there is a paucity of crucial biological data, such as pubertal onset, which has direct and significant applications to improved management of ex situ cheetah populations. This study aimed to determine age of pubertal onset in ex situ male cheetahs using non-invasive fecal steroid hormone monitoring and body weights. Fecal samples from 12 male cheetahs from four institutions were collected 2-3 times weekly from 1 to 42 months of age. Fecal androgen and glucocorticoid metabolites were analyzed using enzyme immunoassays previously validated for use with cheetah feces. Animal body weights were recorded monthly. Fecal hormone and body weight data were analyzed using generalized linear mixed models. Androgen concentrations exhibited an increase to levels similar to those observed in adult males by 18-24 months of age, and males attained adult body weights by 21 months of age. Based on these weight data and the initial increase in androgens toward adult concentrations, males were considered pubertal from 18 to 24 months of age. Glucocorticoid concentrations and amplitude of concentration over baseline were also increased during this period. Knowledge about the physiological changes associated with puberty is useful for management and improving reproductive success of cheetah populations under human care, particularly for determining timing of litter separation from dam, littermate dispersal and when to introduce potential breeding pairs.


Asunto(s)
Peso Corporal/fisiología , Heces/química , Hormonas/metabolismo , Pubertad/metabolismo , Acinonyx , Animales , Gatos , Masculino , Maduración Sexual
13.
Gen Comp Endocrinol ; 225: 104-116, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26393308

RESUMEN

Routine faecal steroid monitoring has been used to aid the management of five captive Asian elephant (Elephas maximus) females at Chester Zoo, UK, since 2007. Progestagen analysis initially revealed synchronised oestrous cycles among all females. However, a 14- to 20-week period of temporary acyclicity subsequently occurred in three females, following several management changes (increased training, foot-care and intermittent matriarch removal for health reasons) and the initiation of pregnancy in another female. The aim of this study was to retrospectively investigate whether these management changes were related to increased adrenal activity and disruption of ovarian activity, or whether social factors may have been involved in the temporary cessation of cyclicity. Faecal samples collected every other day were analysed to investigate whether glucocorticoid metabolites were related to reproductive status (pregnant, cycling, acyclic) or management (training, foot-care, matriarch presence). Routine training and foot-care were not associated with adrenal activity; however, intensive foot-care to treat an abscess in one female was associated with increased glucocorticoid concentration. Matriarch presence influenced adrenal activity in three females, being lower when the matriarch was separated from the group at night compared to being always present. However, in the females that exhibited temporary acyclicity, there was no consistent relationship between glucocorticoids and cyclicity state. Although the results of this study do not fully explain this occurrence, the highly synchronised nature of oestrous cycles within this group, and the concurrent acyclicity in three females, raises the question of whether social factors could have been involved in the temporary disruption of ovarian activity.


Asunto(s)
Animales de Zoológico , Conducta Animal/fisiología , Ciclo Estral/fisiología , Glucocorticoides/análisis , Progestinas/análisis , Conducta Social , Animales , Elefantes , Femenino , Embarazo , Reproducción
14.
Gen Comp Endocrinol ; 214: 186-94, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25150145

RESUMEN

Ex situ populations of endangered species such as the black rhinoceros play an important role in global conservation strategies. However, the European captive population of eastern black rhinoceros is performing sub-optimally, with growth rates and genetic viability limited by low birth rates and high reproductive skew. We investigated several intrinsic differences between parous and nulliparous females that may underlie differences in reproductive success, including ovarian cyclicity, adrenal activity, behaviour and body condition. Faecal samples were collected from 39 females (17 parous, 15 nulliparous and 7 pre-reproductive) at 11 zoological institutions, every other day for between 4months and 6years. Progestagen metabolite concentration indicated that although all non-pregnant females exhibited ovarian activity, irregular cyclicity was common. Longer cycles (>40days) were more common in nulliparous females and periods of acyclicity observed more often in females that had not bred for at least 7years. Even when endocrine data indicated clear ovarian activity, overt behavioural signs of oestrus were not always apparent, particularly among nulliparous females. Faecal glucocorticoids did not differ between parous and nulliparous females, although did differ according to individual temperament. More unpredictable temperaments were associated with higher glucocorticoids, and nulliparous females tended to be rated as more unpredictable. Finally, nulliparous females had higher body condition scores than parous females. This is the first comprehensive survey of the reproductive physiology of this European captive population, and highlights a number of intrinsic differences related to parity, which may underlie differences in reproductive success among captive female black rhinoceros.


Asunto(s)
Estro/fisiología , Fertilidad/fisiología , Ovario/fisiología , Perisodáctilos/fisiología , Reproducción/fisiología , Conducta Sexual Animal/fisiología , Glándulas Suprarrenales/metabolismo , Animales , Especies en Peligro de Extinción , Heces/química , Femenino , Glucocorticoides/metabolismo , Paridad , Embarazo
15.
Gen Comp Endocrinol ; 213: 40-9, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25562628

RESUMEN

Among natural populations of polygynous species, males often vary in their lifetime reproductive success. However, in managed populations of endangered species, either in situ or as part of captive breeding programmes, it is important to understand why differences in reproductive success occur. The European captive population of the critically endangered eastern black rhinoceros is currently under-performing relative to their wild counterparts, with low reproductive output and high reproductive skew limiting growth and genetic diversity. To investigate why over 40% of captive males fail to breed, faecal samples were collected weekly from 23 males at 12 institutions across Europe for 4-32 months. Testosterone metabolite concentration was compared between proven and non-proven males and a number of intrinsic and extrinsic factors that could influence reproductive success were also investigated. Males that sired within the last 3½ years had significantly higher androgen concentrations than non-proven males, and average testosterone was positively correlated with the number of offspring sired per year spent in the reproductive age class. Proven and non-proven males did not differ in their body condition, or in average faecal glucocorticoid concentration. Differences in individual temperament were associated with adrenal activity, but did not correlate with reproductive category. Highest testosterone concentrations were observed in proven males that were housed with females during oestrus, and lowest concentrations in non-proven females not housed with females at all during the study period. Further work is necessary to determine whether proven males had higher testosterone due to underlying differences associated with quality, or whether external stimuli such as access to females could influence testosterone concentration and increase a male's chances of becoming a successful breeder.


Asunto(s)
Heces/química , Fertilidad/fisiología , Perisodáctilos/fisiología , Reproducción/fisiología , Conducta Sexual Animal/fisiología , Testosterona/sangre , Animales , Cruzamiento , Femenino , Masculino , Preferencia en el Apareamiento Animal/fisiología , Perisodáctilos/sangre , Medio Social
16.
Eat Behav ; 53: 101872, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537417

RESUMEN

Exposing children to adults eating a raw vegetable with positive facial expressions ('positive modelling') increases children's consumption of the modelled vegetable. However, whether repeated versus a single exposure to positive modelling enhances this effect, and whether it generalises to a non-modelled vegetable, remains to be examined. Hence, this study examined the effect of a single exposure, versus repeated, exposure to positive modelling on children's acceptance and intake of a modelled and non-modelled vegetable. Children aged 5-6 years (N = 153; 81 males, 72 females) were randomised to one of three conditions in which they had i) a single or ii) repeated exposure to a video of adults eating raw broccoli with positive facial expressions or iii) were exposed to a no-food control video. Children's acceptance (measured as willingness to try and number of tastes), intake and liking of a modelled (raw broccoli) and non-modelled vegetable (raw mangetout) were measured. Children had greater raw broccoli consumption and liking if they had received repeated exposure to positive modelling, compared to children who had received a single exposure, but not compared to children in the control condition. Children's mangetout intake was greater in the single (versus repeated) positive condition, but this effect was not dependent on time. There was no effect on children's vegetable acceptance. Repeatedly exposing children to adults enjoying a vegetable encourages children's intake of the modelled vegetable in comparison to a single exposure. Thus, repeated exposure to others' food enjoyment may be a practical and useful strategy to encourage children's vegetable consumption.


Asunto(s)
Expresión Facial , Preferencias Alimentarias , Verduras , Niño , Preescolar , Femenino , Humanos , Masculino , Brassica , Ingestión de Alimentos/psicología , Conducta Alimentaria/psicología , Preferencias Alimentarias/psicología
17.
Gen Comp Endocrinol ; 186: 16-24, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23462197

RESUMEN

Endocrinology is a useful tool for conservation biologists and animal managers, and measuring glucocorticoids can help understand biological mechanisms associated with species decline and animal welfare. The current study describes the development and optimization of a glucocorticoid enzyme immunoassay (EIA) to non-invasively assess adrenal activity in a variety of taxa. The antiserum (CJM006) was raised in rabbits to a corticosterone-3-CMO-BSA immunogen and used in a standard competitive EIA system. However, the EIA initially produced results with unacceptably high inter-assay variation, attributed to consistent patterns observed within the optical density of developing plates. To determine the cause of this variability, a number of factors were examined using synthetic corticosterone standard and endogenous faecal extract, including: plate type (Nunc MaxiSorp® II versus Immulon IB plates); the use of non-specific secondary antibody; type (artificial versus natural) and presence (light versus dark) of light during incubation; plate loading temperature (4°C versus room temperature); and substrate reagent temperature (4°C versus room temperature). Results indicated that variability was associated with plate location effects, which were not initially detected because control samples were always run in the same positions across plates. Light and temperature were the two major factors that affected EIA reliability. For this assay, the standard protocol required slight modification, with the optimal protocol using Nunc MaxiSorp® plates, room temperature substrate reagents and dark incubation conditions. Following optimization, this EIA was then validated biochemically for 38 species, through parallel displacement curves and interference assessment tests of faecal and urine samples. Additionally, biological validation was performed opportunistically in a subset of species, with use of this EIA demonstrating significant elevations in faecal glucocorticoid metabolites following potentially challenging events. In summary, this glucocorticoid EIA cross-reacts with excreted glucocorticoid metabolites across a wide range of taxa, including ungulates, primates, felids, birds, rodents and amphibians. We conclude that when used with optimal reagent and incubation conditions, this EIA will be useful for non-invasive monitoring of adrenal activity in a wide range of wildlife species.


Asunto(s)
Glucocorticoides/análisis , Técnicas para Inmunoenzimas/métodos , Anfibios/metabolismo , Animales , Aves/metabolismo , Primates/metabolismo , Roedores/metabolismo
18.
Gen Comp Endocrinol ; 186: 72-9, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23474330

RESUMEN

Faecal glucocorticoid metabolite (fGCM) concentrations have been used to evaluate adrenal activity in a variety of species; including as an indicator of the physiological response to social stress. However, across studies, the relationships between dominance rank, social behaviours and adrenal responses can be inconsistent. Differences in the relationship between rank and glucocorticoids may be due to the relative costs of social status, and the relative frequencies of social stressors and potential coping mechanisms. However, the differences in observed relationships between specific social behaviours and glucocorticoids may be partly explained by sampling frequency, as studies often use average fGCM concentrations collected over a period of weeks or months, rather than fGCM concentrations that are temporally-matched with behavioural data. In this study, we directly compared long-term average and temporally-matched data to determine whether particular social behaviours were related to adrenal activity in female Barbary macaques (Macaca sylvanus) at Trentham Monkey Forest, UK; and whether observed relationships were consistent using these two approaches. Average rates of autogrooming were positively correlated with average fGCM; however, this relationship was not robust in temporally-matched samples. Instead, specific social behaviours associated with agonism were associated with fGCM in temporally-matched samples within individuals. These results indicate that analyses of relationships using long-term average fGCM and temporally-matched samples do not necessarily provide comparable results, highlighting that study design is critical in determining associations between an individual's social behaviour and the relative physiological costs involved.


Asunto(s)
Glándulas Suprarrenales/metabolismo , Heces/química , Glucocorticoides/metabolismo , Macaca/metabolismo , Conducta Social , Animales , Conducta Animal/fisiología , Femenino , Macaca/fisiología , Masculino
19.
Front Psychol ; 14: 1252369, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38274690

RESUMEN

Introduction: Food enjoyment can be conveyed through facial expressions. Observing others' enjoyment of food has been found to influence adults' desirability of liked and disliked food. Exposing adults to other eaters enjoying nutritious foods that are typically disliked (e.g., vegetables) could enhance the consumption of vegetables by young adults. However, this remains to be examined in young adult populations. This study examined the effect of models' facial expressions towards raw broccoli on young adult women's change in liking and change in desire to eat a modelled vegetable (raw broccoli) and a non-modelled vegetable (cucumber). Methods: Young adult women (N = 205) were randomised to watch a video of unfamiliar adult models eating raw broccoli with a positive, negative, or neutral facial expression. Participants' change in liking and change in desire to eat the modelled and non-modelled vegetable was examined. Results: Observing models conveying negative facial expressions whilst eating raw broccoli resulted in a statistically significant reduction in liking ratings of broccoli, but not cucumber. There was no effect of models' facial expressions on the change in desire to eat foods. Discussion: These findings suggest that watching others express a negative facial expression whilst eating a raw vegetable reduces women's liking of the modelled vegetable, in the absence of a significant change to their desire to consume these foods. This highlights the power of others' negative facial expressions on food liking. Further work is needed to establish the effect of others' facial expressions on vegetable intake.

20.
Animals (Basel) ; 12(7)2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35405799

RESUMEN

Cheetahs have been the subject of reproductive study for over 35 years, yet steroid hormone activity remains poorly described after ovulation. Our objective was to examine and compare fecal progestagen (fPM), estrogen (fEM), and glucocorticoid (fGM) metabolite concentrations post-ovulation in pregnant and non-pregnant animals to better understand female physiology (1) during successful pregnancy, (2) surrounding frequent non-pregnant luteal phases, and (3) after artificial insemination (AI) to improve the low success rate. Secondarily, the authors also validated a urinary progestagen metabolite assay, allowing pregnancy detection with minimal sample collection. Fecal samples were collected from 12 females for ≥2 weeks prior to breeding/hormone injection (the PRE period) through 92 days post-breeding/injection. Samples were assessed for hormone concentrations using established enzyme immunoassays. Urine samples were collected for 13 weeks from 6 females after natural breeding or AI. There were no differences among groups in fGM, but in pregnant females, concentrations were higher (p < 0.01) in the last trimester than any other time. For pregnant females that gave birth to singletons, fGM was higher (p = 0.0205), but fEM tended to be lower (p = 0.0626) than those with multi-cub litters. Our results provide insight into the physiological events surrounding natural and artificially stimulated luteal activity in the cheetah.

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