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Funder: University of Zurich; Id: http://dx.doi.org/10.13039/501100006447, Funder: MAVA Foundation, Funder: Mammal Research Institute at the University of Pretoria, The ability of dispersing individuals to adjust their behaviour to changing conditions is instrumental in overcoming challenges and reducing dispersal costs, consequently increasing overall dispersal success. Understanding how dispersers' behaviour and physiology change during the dispersal process, and how they differ from resident individuals, can shed light on the mechanisms by which dispersers increase survival and maximise reproduction. By analysing individual behaviour and concentrations of faecal glucocorticoid metabolites (fGCM), a stress-associated biomarker, we sought to identify the proximate causes behind differences in survival and reproduction between dispersing and resident meerkats Suricata suricatta. We used data collected on 67 dispersing and 108 resident females to investigate (a) which individual, social and environmental factors are correlated to foraging and vigilance, and whether the role of such factors differs among dispersal phases, and between dispersers and residents; (b) how time allocated to either foraging or vigilance correlated to survival in dispersers and residents and (c) the link between aggression and change in fGCM concentration, and their relationship with reproductive rates in dispersing groups and resident groups with either long-established or newly established dominant females. Time allocated to foraging increased across dispersal phases, whereas time allocated to vigilance decreased. Time allocated to foraging and vigilance correlated positively and negatively, respectively, with dispersers' group size. We did not find a group size effect for residents. High proportions of time allocated to foraging correlated with high survival, and more so in dispersers, suggesting that maintaining good physical condition may reduce mortality during dispersal. Furthermore, while subordinate individuals rarely reproduced in resident groups, the conception rate of subordinates in newly formed dispersing groups was equal to that of their dominant individuals. Mirroring conception rates, in resident groups, fGCM concentrations were lower in subordinates than in dominants, whereas in disperser groups, fGCM concentrations did not differ between subordinates and dominants. Our results, which highlight the relationship between behavioural and physiological factors and demographic rates, provide insights into some of the mechanisms that individuals of a cooperative species can use to increase overall dispersal success.

Vertebrate muscle myosin, the motor protein, has evolved over long periods of time. In the present study, we specifically aimed at identifying how this evolution has fine-tuned myosin conformational states to the specific needs of organisms with different body masses. As myosin has two different relaxed states (super-relaxed and disordered-relaxed), we initially hypothesized that a linear positive correlation would exist between the amount of myosin molecules in the super-relaxed conformation and the body weight of the organisms in which they are expressed. To verify this hypothesis, we extracted muscle fibres from multiple vertebrate species with body weights ranging from grams to tons. By using a loaded Mant-ATP chase protocol, we observed that vertebrate species with body weights above 1000 kilograms have significantly higher proportions of super-relaxed myosin proteins in their muscle fibres. As myosin heads in the super-relaxed conformation consume five times less ATP than the ones in the disordered-relaxed state, our finding suggest that heavy vertebrate animals have adapted their motor protein conformations to potentially avoid inappropriate and large energy consumption in their metabolically demanding muscles.

In a time of increasing environmental change caused by anthropogenic disturbance, there is a greater need to understand animal adaptations to manmade environments. In this regard, the measurement of stress-related endocrine markers provides a useful tool to examine the impact of environmental challenges and the physiological consequences for wildlife occupying such space. The aims of the present study were to validate fecal glucocorticoid metabolite (fGCM) concentrations as a measure of stress using samples from a male African clawless otter (Aonyx capensis; n = 1) and to compare fGCM concentrations of otters occurring in a transformed and in 2 natural areas in South Africa. From the 5 different enzyme-immunoassays (EIA) tested, a cortisol and oxoetiocholanolone (measuring 11,17 dioxoandrostanes) EIA revealed the highest response (74% and 48% increase, respectively) 30 and 24 hours after a stress event (translocation of a captive individual as part of its rehabilitation prior to release), respectively. For both EIAs, fGCM concentrations were comparable for samples collected up to 3 h post-defecation. Using the cortisol EIA for subsequent analyses, fGCM concentrations of animals from the transformed area (n = 20; mean [± SD]: 0.468 [± 0.539] µg/g dry weight [DW]) were significantly higher (P = 0.013) than those from otters in the natural areas (n = 17; 0.242 [± 0.226] µg/g DW). These preliminary results suggest that African clawless otters may have increased adrenocortical activity that could be due to conditions linked to living in a transformed environment.

There are few stressful factors which have been investigated to affect adrenocortical function in the African wild dog (AWD) Lycaon pictus. Understanding what animals perceive as stressors is important for not only the implementation of management practices promoting general animal welfare in captivity, but also because a prolonged stress perception is known to disrupt reproduction, immune function and ultimately pose a threat to survival. In this regard, faecal glucocorticoid metabolite (fGCM) measurements are commonly used as a non-invasive approach to assess the impact of factors which may be acting as perceived stressors in wildlife. This study was aimed at determining if there are significant differences in AWD fGCM concentrations as a result of sex, presence of absence of an injury, age-class, body condition, dietary provisioning (through stable nitrogen (δ15N) and carbon (δ13C) isotope analysis), hierarchal status, and setting (i.e. captive or free-ranging). A total of 47 faecal samples were collected immediately post-defaecation from 39 AWDs across four free-ranging sites (Hluhluwe-iMfolozi Park, Madikwe Game Reserve, Kruger National Park and the Waterberg), two permanently captive sites (Johannesburg and Pretoria Zoo), and four temporary captive holding facilities (Hoedspruit Endangered Species Centre and Maremani, Tembe and Zimanga bomas) in South Africa. Captive AWDs had distinctively higher fGCM levels than their free-ranging counterparts, regardless of sex, body condition, hierarchal status, age-class or dietary provisioning. The present study is the first to assess physiological stress responses across permanently captive, temporarily captive and free-ranging AWDs within the South African managed metapopulation, while incorporating the use of stable isotope analysis to quantify differences in dietary isotopic profiles between these different settings. Ultimately this demonstrates the usefulness of fGCM analysis as a tool for assessing animal welfare in both captive and free-ranging AWDs, and underpins the importance of understanding factors perceived as stressors for the management of the species. Keywords: animal welfare, body condition scoring, faecal glucocorticoid metabolite monitoring, managed metapopulation, stress, wildlife management.

Reports of the vaginal flora of wild cats such as lions or leopards are scarce. The micro-organisms most commonly found in the vagina of clinically healthy cats are aerobic bacteria such as coagulase-negative Staphylococcus, Streptococcus canis, and Escherichia coli. Simonsiella spp are large Gram-negative bacteria belonging to the Neisseriaceae family, typically found in the oral cavity and upper respiratory tract of many species. To date, there are no reports of the detection of Simonsiella spp in the vaginal flora of any felid. For a period of six months, daily behaviour monitoring was performed on six captive lionesses at a South African conservation centre, in parallel with the collection of vaginal swabs and interpretation of the resultant vaginal cytologies every other day. Oestrus was identified by typical female reproductive behaviours, as well as by enlarged and separated vulvar lips, and a predominant proportion of superficial cornified cells, clearing of the background, and high bacterial presence in the vaginal smear. Simonsiella spp were identified by their characteristic morphology in 58% (60 of 103) of the vaginal samples collected during oestrus. They were also found in oral swabs of three out of three lions tested. Additionally, Simonsiella spp were opportunistically found in a vaginal smear from a zoo housed female Sri Lankan leopard in oestrus, during a routine reproduction assessment. The finding of Simonsiella spp may be more common than previously suspected, transitory, and without detectable clinical relevance. A connection between occurrence of these bacteria and oestrus was apparent.

The National Research Foundation, South Africa and a postgraduate bursary from the DST-NRF SARChI chair for Mammal behavioural ecology and physiology to (NCB).

A physiological stress response can be triggered by a variety of intrinsic and extrinsic stimuli, but minimal information is available about the physiological stress response related to pain in wildlife. Recently established techniques now allow the non-invasive measurement of faecal glucocorticoid metabolite (fGCM) concentrations to monitor the physiological stress response in giraffe. We examined the consequences of injury of various severities and loss of body condition in relation to glucocorticoid output in free-ranging giraffes. Body condition (BC) was visually estimated based on the amount of fat and muscle covering the bones, using a species-specific scoring system (one – emaciated to eight – obese). An adapted animal trauma triage scoring system was also applied to evaluate the severity of injuries observed. Individual fGCM concentrations were determined to assess stress-related glucocorticoid output using an enzyme immunoassay technique, and compared with assigned BC and injury scoring. Significantly elevated fGCM levels were found in injured individuals that showed wounds with deep tissue involvement and/or poor BC, but not in individuals that showed superficial wounds. Responsible for the observed changes in fGCM levels may be a combination of differences in the severity of the injuries and the subsequent degree of pain associated with it, the influence of the stress response on the energetic condition, and the duration of the injuries. The results of this study are somewhat limited due to the small sample size, and therefore the effect of food intake on the body conditions cannot be controlled for. However, euthanasia is a common management tool used to prevent unnecessary suffering, nevertheless, especially in wild animals the severity of an injury and the associated pain perceived may be difficult to assess. Combining an assessment of BC and analysis of individual stress-hormone levels can help improve health assessments in free-ranging giraffes and thus assist management decisions.

Non-invasive techniques for the monitoring of animal well-being, such as faecal hormone analysis, are increasingly becoming some of the most desirable methods for addressing practical conservation questions. Despite the widespread use of faecal hormone measurements for monitoring responses to stressors and its known applicability to African wild dogs Lycaon pictus, the potential influence of time of collection post-defaecation on stress-steroid concentrations in faecal matter has not yet been investigated. In the present study, we determined the rate at which African wild dog faecal glucocorticoid metabolite (fGCM) concentrations change over a 16-day period post-defaecation, in order to provide recommendations for best sampling practice. No significant changes in fGCM concentrations were found for the first 48 h post-defaecation. However, an approximately 30% increase in fGCM concentrations were already noted between day 1 and day 2, followed by a significant 150% increase at 96 h post-defaecation. We therefore suggest that respective faecal material should be collected within the first 24 h post-defaecation to ensure the reliability of fGCM analysis. In addition, we collected baseline data denoting the fGCM concentrations of captive African wild dogs sampled across three South African captive sites. Determined baseline fGCM concentrations differed between African wild dogs at the sites sampled. These data could be used in future studies aimed at identifying the key stressor complexes perceived by captive African wild dogs in order to improve management strategies.

Living under predation risk may alter both behaviour and physiology of potential prey. In extreme cases, such alterations may have serious demographic consequences, and recent studies support that non-lethal effects of predation may have broad ecological consequences. However, behavioural and physiological responses to predation risk may be related to trade-offs associated with resource acquisition and direct predation risk. We validated an enzyme-linked immunoassay (EIA) for non-invasive monitoring of stress in plains zebras (Equus quagga) from faecal material. We used this assay in combination with behavioural data to assess if plains zebras living with and without lions (Panthera leo) in a mountain savannah in southern Africa differed in behaviour and physiology, and if such differences were influenced by seasons with contrasting resource availability. Zebra group sizes did not differ between areas with and without lions, but zebra groups had more juveniles in an area with lions than groups in an area without lions, but only during the wet season. Similarly, we observed differences in individual vigilance, foraging behaviour and stress hormone concentrations, but all these differences were influenced by seasons. Despite these seasonal influences, our study did not suggest that zebras in an area with lions spent a higher proportion of time being vigilant, a lower proportion of time foraging, or had higher stress hormone levels. Our results instead suggest that zebras' responses to lion presence were highly context dependent and the result of complex interactions between resource abundance and cues about predation risk. Because of the obvious ecological and evolutionary ramifications of such findings, we argue that further research is needed to define the spatial and temporal scales over which predators impose indirect effects on their prey.

The golden langur (Trachypithecus geei) is an endangered primate endemic to northern India and Bhutan. The main stressors to the species are habitat degradation and fragmentation. Non-invasive fecal glucocorticoid metabolite (fGCM) analysis is a powerful tool for assessing stress associated with environmental disturbances in wildlife. However, interspecific differences in glucocorticoid metabolism require careful selection of the antibody used in their quantification. The goals of this study were to: 1) validate an enzyme immunoassay (EIA) to determine fecal GC metabolite (fGCM) concentrations in the golden langur and 2) compare fGCM concentrations between golden langurs living under different environmental conditions. We compared five enzyme immunoassays for determining stress related physiological responses in golden langurs by performing an adrenocorticotropic stimulation test in both sexes. Our validations identified an 11-oxoaetiocholanolone EIA detecting 11, 17 dioxoandrostanes as the most suitable assay for monitoring adrenocortical activity in the species. FGCM concentrations from semi-captive temple langurs were significantly higher than respective stress steroid concentrations in free-ranging or pet/zoo langurs. This study presents a validated practical method for non-invasive monitoring of adrenocortical function in this rare and declining species.

Stress in animals has been linked to behavioural and physiological changes in response to environmental, social and anthropogenic stimuli. Hence, stress-related responses in animals, especially in rodents, have been used as biological indicators of ecosystem health. This study aimed to establish an enzyme immunoassay (EIA) for monitoring adrenocortical activity in free-ranging Namaqua rock mice Micaelamys namaquensis (Rodentia: Muridae) using faeces as a prerequisite for assessing the effects of anthropogenic land use and season on faecal glucocorticoid metabolite (fGCM) concentration. Rodents were live-trapped seasonally across four land use types: an agricultural crop farm, an agricultural livestock farm, a human-populated site and a nature reserve; all situated in Limpopo Province, South Africa. Determined fGCM concentrations from capture and recapture events were used for biologically validating an EIA detecting steroids with a 5α-3β-11β-diol structure. Recapturing resulted in a significant overall 40% elevation of individual fGCM concentrations demonstrating the effectiveness of the chosen EIA to reliably detect glucocorticoid output in the study species. Neither land use type nor season affected fGCM concentrations in the species, suggesting that land use and season-related environmental changes do not necessarily act as stressors for M. namaquensis, presumably due to their adaptive and resilient nature. Such species can be used to identify ecosystems affected by human-mediated disturbances and allow insights into the management and restoration of these threatened ecosystems and their associated species.

The giraffe (Giraffa camelopardalis) is usually described as an exclusive browser, feeding only on shrubs and trees, preferrably between 2 and 5 m above ground (Lamprey, 1963; McNaughton & Georgiadis, 1986; Ciofolo & Le Pendu, 2002). Although browsing seems to be an easier form of feeding for giraffes in terms of accessibility and vigilance (Young & Isbell, 1991), a few studies mention that the giraffe also ‘very occasionally’ feeds on grass (Pienaar, 1963; Du Toit, 2005). To be able to graze, a giraffe has to adopt the typical ‘drinking position’, where the forelegs are splayed out laterally, and sometimes the carpal joints are also flexed. In this position, the animals are particularly vulnerable to predators (Periquet et al., 2010). In this note, we show that grazing, although not a core activity, is a recurrent event in a nutrient-poor environment such as Hwange National Park and suggest a possible function.

Free-ranging African elephants Loxodonta africana use their front feet frequently during the process of foraging and this could be the reason for the high prevalence of physical injuries to these parts of the body. Although the occurrence of severe lameness caused by foot lesions in adult elephants has already been investigated and the clinical and pathological findings have been reported, the effect of foot injuries on glucocorticoid levels as a potential physiological stress response has not been examined. Given the practical difficulties involved in monitoring unpredictable events in free-ranging animals, like the occurrence of foot injuries in elephants, it is not surprising that information regarding the endocrine correlates of physical injury is still limited for elephants. In our study we investigated the effects of foot injuries on concentrations of faecal glucocorticoid metabolites (GCM), body condition score (BCS) and reproductive behaviour in two GPS/radio-collared elephant bulls in the Kruger National Park, South Africa. We monitored the bulls aged 40+ (Bull 1) and 30+ (Bull 2) 2-3 times per week for 13 months starting in June 2007 and frequently collected faecal samples for non-invasive hormone monitoring. Faecal samples were lyophilised, extracted and assayed with an enzyme immunoassay which detects GCM with a 3a-hydroxy-11-oxo-structure. Both bulls acquired foot injuries (right-front), which caused temporary lameness, but the effect of injury on GCM concentration differed between bulls (P , 0.001). In Bull 1 the injury lasted 6 250 days and was associated with an up to four-fold increase in GCM concentrations (P , 0.001) and his BCS reduced from ’good’ to ’very thin’ by the end of the injury period. In Bull 2 the injury lasted 65 days and was associated with a smaller increase in GCM concentrations (P ¼ 0.03) together with a reduced loss in condition when compared to Bull 1. Following recovery, the condition of both bulls improved progressively and faecal GCM returned to baseline concentrations. Collectively, the data clearly underlined the value of non-invasive hormone measurements as a tool to provide information on the level of stress experienced by elephants. Thus, monitoring GCM levels could help improve the assessment of an elephant’s state of health.

Androgen measurements in urine and/or feces represent a potentially important tool for monitoring testicular endocrine function in the African elephant. To assess the feasibility of this approach, the aims of the present study were to: 1) examine the presence and relative abundance of immunoreactive testosterone (iT) and its 5α-reduced 17-oxometabolite epiandrosterone (iEA) in African elephant excreta, and 2) compare urine and fecal androgen profiles in animals of different ages and during the musth and non-musth condition. Urine and fecal samples were collected over periods of up to 3 years from five bulls (ages 7–24 years) living in three mixed social groups. In parallel, indications of musth were recorded by keeper staff as an independent marker of male androgen status. Measurements of iT and iEA were carried out by enzymeimmunoassay (EIA) following methanolic extraction of hydrolyzed urine and lyophilized fecal powder. High-pressure liquid chromatography (HPLC) of musth phase samples confirmed the presence of substantial quantities of testosterone (T) and epiandrosterone (EA) in both urine and feces. EA was predominant in feces, whereas T was more abundant in urine. In each male, the two androgen measures were significantly correlated (feces, r = 0.71–0.93, P < 0.0001; urine, r = 0.86–0.91, P < 0.0001), as were fecal and urinary concentrations of each of the two androgens measured (r = 0.35–0.77, P < 0.0001). Moreover, in the two oldest males that showed clear signs of musth, levels of iEA and iT were markedly elevated during musth compared to non-musth periods (differences were significant for feces in both animals, but in urine only for one). Collectively, the data show that measurement of urinary and fecal androgens generates useful information on gonadal status in male African elephants, and as such should provide new opportunities to improve the management and welfare of bulls maintained in captivity, as well as to examine physiological correlates of reproductive function in free-ranging animals. Zoo Biol 21:27–36, 2002. © 2002 Wiley-Liss, Inc.

Reasons for performing study Commingling of horses from various populations, together with stress associated with transport and confinement at a sales complex, may predispose horses to EHV-1 and -4 shedding and transmission. Current information on the prevalence and associated risk factors of EHV-1 and -4 in South Africa is limited. Relevant research could enhance scientific-based risk management strategies for horses attending sales events. Objectives Detect nasal shedding of EHV-1 and -4 at a sales event. Identify the temporal pattern of viral shedding. Investigate the association between clinical signs and EHV-1 and -4 shedding. Identify risk factors for EHV-1 and -4 shedding and transmission. Study design Prospective cohort study. Methods Data was collected over a 9 day period during August 2013 at the National Two Year Old Sales in Germiston, South Africa. The study population included 90 Thoroughbreds (51 colts, 39 fillies) in their second year of life that originated from 8 studs situated in 3 provinces. Nasal swabs were collected from each horse on arrival and on departure from the event. During their stay horses were monitored twice daily for pyrexia and once daily for nasal discharge. Nasal swabs were collected daily from any horse with nasal discharge and/or pyrexia. Nasal swabs were submitted for qPCR to detect EHV-1 and -4. Results No EHV-1 shedding was detected; however, 14.4% of the population shed EHV-4. A biphasic shedding pattern with peaks one day post arrival and on the first day of auction was observed. Pyrexia, with or without nasal discharge, was observed prior to first shedding in 61.5% of EHV-4-positive horses. Province, associated longer travel duration and smaller resident horse populations on farms of origin were associated with increased risk of EHV-4 shedding. Conclusions Young Thoroughbreds consigned to a South African sale shed EHV-4. Pyrexia proved useful to identify impending EHV-4 shedding. Ethical animal research: The study was approved by the Animal Ethics Committee (AEC) of the University of Pretoria (Study V040-13). Informed, written consent for participation was obtained from the owners of each of the studs included in the study. Sources of funding: Funding for this study was provided by Racing South Africa and the Departments of Companion Animal Clinical Studies and Production Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria. Competing interests: None.

Periods of reproduction are linked to changes in male behaviour, physiology and physical parameters. Although high androgen concentrations hold numerous advantages, especially during reproductive periods, chronically elevated androgen concentrations over long periods may be costly and thus need to be regulated. As such seasonal breeders will display temporary elevated androgen concentrations, increased testis levels and mating behaviour only during important reproductive periods. We studied a captive as well as a free‐ranging population of the polygamous strepsirrhine primate, the African lesser bushbaby Galago moholi, to clarify the link between androgen concentration, reproductive behaviour and testis size and the importance of the two mating periods observed in the species. To monitor androgen patterns, we used faecal sampling and quantification of faecal androgen metabolites (fAM). We additionally collected testicular measurements and behavioural data. G. moholi displayed a strong degree of reproductive seasonality, with maximum fAM concentration, testicular volume (TV) and behavioural activity focused on the mating periods. In contrast to other studies, TV increased prior to fAM, with reproductive activity being initiated only when fAM concentrations reached high levels. Changes in TV and fAM concentrations were not significantly different between both mating periods. Based on the absence of a significant difference between mating seasons, it is likely that male G. moholi attempt to maximize their reproductive success by utilizing both mating periods equally. This study is the first to describe the reproductive endocrine pattern linked to physical changes and mating behaviour in any galago species, increasing our understanding of the reproductive biology of nocturnal, polygamous primates.