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can an herbivore affect where a top predator kills its prey by modifying woody vegetation structure?in large mammal communities, little is known about modification of interspecific interactions through habitat structure changes. we assessed the effects of african elephants (loxodonta africana) on features of woody habitat structure that can affect predator-prey interactions. we then explored how this can influence where african lions (panthera leo) kill their prey. indeed, lions are stalk-and-ambush predators and habitat structure and concealment opportunities are assumed to influence their hu ...202032060732
serum health biomarkers in african and asian elephants: value ranges and clinical values indicative of the immune response.serum biomarkers indicative of inflammation and disease can provide useful information regarding host immune processes, responses to treatment and prognosis. the aims of this study were to assess the use of commercially available anti-equine reagents for the quantification of cytokines (tumor necrosis factor-alpha (tnf-α), interferon-gamma (ifn-γ), interleukins (il) 2, 6, and 10) in african (loxodonta africana, n = 125) and asian (elephas maximus, n = 104) elephants, and alongside previously val ...202032992555
noninvasive sampling for detection of elephant endotheliotropic herpesvirus and genomic dna in asian (elephas maximus) and african (loxodonta africana) elephants.elephant endotheliotropic herpesvirus (eehv) hemorrhagic disease (eehv-hd) threatens asian elephant (elephas maximus) population sustainability in north america. clusters of cases have also been reported in african elephants (loxodonta africana). risk to range country elephant populations is unknown. currently, eehv detection depends upon sampling elephants trained for invasive blood and trunk wash collection. to evaluate noninvasive sample collection options, paired invasively collected (blood, ...202032549575
distinguishing extant elephants ivory from mammoth ivory using a short sequence of cytochrome b gene.trade in ivory from extant elephant species namely asian elephant (elephas maximus), african savanna elephant (loxodonta africana) and african forest elephant (loxodonta cyclotis) is regulated internationally, while the trade in ivory from extinct species of elephantidae, including woolly mammoth, is unregulated. this distinction creates opportunity for laundering and trading elephant ivory as mammoth ivory. the existing morphological and molecular genetics methods do not reliably distinguish th ...201931827140
weigh and see-body mass recordings versus body condition scoring in european zoo elephants (loxodonta africana and elephas maximus).regular body mass (bm) monitoring plays a key role in preventative health care of zoo animals. in some species, including african (loxodonta africana) and asian elephants (elephas maximus), the process of weighing can be challenging, and alternative methods such as visual body condition scoring (bcs) have been developed. we investigated the temporal development of both parameters regarding correlation patterns between them, and their suitability as monitoring measures in dependence of an elephan ...202031737945
individual and environmental risk factors associated with fecal glucocorticoid metabolite concentrations in zoo-housed asian and african elephants.a recent large-scale welfare study in north america involving 106 asian (elephas maximus) and 131 african (loxodonta africana) elephants at 64 accredited facilities identified links (i.e., risk factors) between zoo environmental factors and a number of welfare outcomes (stereotypic behavior, ovarian acyclicity, hyperprolactinemia, walking and recumbence, body condition, health status, serum cortisol). for this population of elephants, we used the same epidemiological methods to examine associati ...201931483790
update on comparative biology of elephants: factors affecting reproduction, health and welfare.asian (elephas maximus) and african (loxodonta africana) elephants serve as important keystone, umbrella and flagship species. despite that, population numbers are declining, due mainly to poaching and habitat destruction. understanding reproductive mechanisms is vital to effective management, particularly insurance populations in captivity, and to that end, long-term biological databases are key to understanding how intrinsic and extrinsic factors affect reproductive function at individual and ...201931471800
development of a multiplex, pcr-based genotyping assay for african and asian elephants for forensic purposes.wildlife crimes and the threats they present to elephant populations raise the need to develop and implement dna-based methodology as an aid for wildlife forensic investigations and conservation efforts. this study describes the development of a tetra-nucleotide repeat str multiplex, genotyping assay that will identify asian elephant (elephas maximus) and african elephant (loxodonta africana) dna. the assay targets six tetra-nucleotide strs and two sex-typing markers simultaneously in both gener ...202031190288
elequant: a developmental framework and validation of forensic and conservation real-time pcr assays.a framework for the development and validation of a qpcr assay for species identification and dna quantification for conservation and forensic purposes is presented. elephants are commonly poached for their ivory tusks, which is the primary driving force behind their endangered status. in addition to poaching and trade, habitat loss due to logging and mining has also resulted in loss of elephants. crimes against animals can be deterred and/or further prosecution sought through testing with foren ...201930721419
when elephants fall asleep: a literature review on elephant rest with case studies on elephant falling bouts, and practical solutions for zoo elephants.little attention has been paid to the resting and sleeping behavior of zoo elephants so far. an important concern is when elephants avoid lying down, due to degenerative joint and foot disease, social structure, or stressful environmental changes. inability or unwillingness to lie down for resting is an important welfare issue, as it may impair sleep. we emphasize the importance of satisfying rest in elephants by reviewing the literature on resting behavior in elephants (loxodonta africana and e ...201829600558
hypermucoviscous/hypervirulent and extensively drug-resistant qnrb2-, qnrs1-, and ctx-m-3-coproducing klebsiella pneumoniae st2121 isolated from an infected elephant (loxodonta africana).the rapid dissemination of extended-spectrum β-lactamases (esbls)-producing enterobacterales from different spheres worldwide over recent years has become a serious problem in both human and veterinary medicine. ctx-m-3-type esbl has only been reported on few occasions, and in brazil the blactx-m-3 gene has been identified only once in clinical strains. in this study, we aimed to molecularly characterize a hypermucoviscous (hm), hypervirulent (hv), and extensively drug-resistant (xdr) klebsiella ...202033176213
genetic connectivity and population structure of african savanna elephants (loxodonta africana) in tanzania.increasing human population growth, exurban development, and associated habitat fragmentation is accelerating the isolation of many natural areas and wildlife populations across the planet. in tanzania, rapid and ongoing habitat conversion to agriculture has severed many of the country's former wildlife corridors between protected areas. to identify historically linked protected areas, we investigated the genetic structure and gene flow of african savanna elephants in tanzania using microsatelli ...202033144949
frenemy at the gate: invasion by pheidole megacephala facilitates a competitively subordinate plant ant in kenya.biological invasions can lead to the reassembly of communities, and understanding and predicting the impacts of exotic species on community structure and functioning is a key challenge in ecology. we investigated the impact of a predatory species of invasive ant, pheidole megacephala, on the structure and function of a foundational mutualism between acacia drepanolobium and its associated acacia-ant community in an east african savanna. invasion by p. megacephala was associated with the extirpat ...202033098658
increasing browse and social complexity can improve zoo elephant welfare.while recent work has assessed how environmental and managerial changes influence elephant welfare across multiple zoos, few studies have addressed the effects of management changes within a single institution. in this paper, we examine how management changes related to social structure and diet affect the behavior of a group of zoo elephants over a 23-month period while also considering underlying factors, such as time of day, hormonal cycle, and individual differences. we recorded individual b ...202033043537
importance of old bulls: leaders and followers in collective movements of all-male groups in african savannah elephants (loxodonta africana).in long-lived social species, older individuals can provide fitness benefits to their groupmates through the imparting of ecological knowledge. research in this area has largely focused on females in matrilineal societies where, for example, older female african savannah elephants (loxodonta africana) are most effective at making decisions crucial to herd survival, and old post-reproductive female resident killer whales (orcinus orca) lead collective movements in hunting grounds. in contrast, li ...202032883968
behavioural variability among captive african elephants in the use of the trunk while feeding.the proboscideans, an order of mammals including elephants, are the largest of the earth lands animals. one probable consequence of the rapid increase of their body size is the development of the trunk, a multitask highly sensitive organ used in a large repertoire of behaviours. the absence of bones in the trunk allows a substantial degree of freedom for movement in all directions, and this ability could underlie individual-level strategies. we hypothesised a stronger behavioural variability in ...202032874780
african elephants interpret a trunk gesture as a clue to direction of interest.orienting to gaze-direction is widespread among animal species, but evidence for spontaneous use of gesture for direction is limited [1]. remarkably, african elephants (loxodonta africana) have been found able to follow human pointing, including subtle actions in which the contralateral hand is used, and in which the body silhouette is not broken [2,3]. the natural origin of this ability is puzzling, as the species is not reported to use trunk- or limb-gesture for showing directions [4]. one nat ...202032810448
circulating nutrients and hematological parameters in managed african elephants (loxodonta africana) over a 1-year period.african elephants (loxodonta africana) are currently considered a vulnerable species. one key to improving methods of species management is to better monitor and understand elephant nutrition. analyzing circulating nutrients is one of the best and least invasive methods of monitoring managed elephant nutrition, but limited reference values are available. this study examined the circulating basic hematology concentrations, minerals, vitamins a, d, and e, and fatty acids of six african elephants ( ...202032633838
international high-risk clone of multidrug-resistant ctx-m-8-producing escherichia coli c-st410 infecting an elephant (loxodonta africana) in a zoo. 202032622999
effects of diet, habitat, and phylogeny on the fecal microbiome of wild african savanna (loxodonta africana) and forest elephants (l. cyclotis).the gut microbiome, or the community of microorganisms inhabiting the digestive tract, is often unique to its symbiont and, in many animal taxa, is highly influenced by host phylogeny and diet. in this study, we characterized the gut microbiome of the african savanna elephant (loxodonta africana) and the african forest elephant (loxodonta cyclotis), sister taxa separated by 2.6-5.6 million years of independent evolution. we examined the effect of host phylogeny on microbiome composition. additio ...202032607180
the vetmax™ m. tuberculosis complex pcr kit detects mtbc dna in antemortem and postmortem samples from white rhinoceros (ceratotherium simum), african elephants (loxodonta africana) and african buffaloes (syncerus caffer).bovine tuberculosis and tuberculosis are chronic infectious diseases caused by the mycobacterium tuberculosis complex members, mycobacterium bovis and mycobacterium tuberculosis, respectively. infection with m. bovis and m. tuberculosis have significant implications for wildlife species management, public health, veterinary disease control, and conservation endeavours.202032600471
mapping and assessing the impact of small-scale ephemeral water sources on wildlife in an african seasonal savannah.in many savannah regions of africa, pronounced seasonal variability in rainfall results in wildlife being restricted to floodplains and other habitats adjacent to permanent surface water in the dry season. during the wet season, rainfall fills small-scale, ephemeral water sources that allow wildlife to exploit forage and other resources far from permanent surface water. these water sources remain difficult to quantify, however, due to their small and ephemeral nature, and as a result are rarely ...202032598524
normalized difference vegetation index, temperature and age affect faecal thyroid hormone concentrations in free-ranging african elephants.conservation biologists can use hormone measurements to assess animals' welfare, reproductive state, susceptibility to stressors, as well as energy expenditure. quantifying hormone concentrations from faecal samples is particularly advantageous as samples can be collected without disturbing animals' behaviour. in order for an endocrine marker to be useful for wildlife managers, we need to understand how extrinsic and intrinsic factors affect hormone concentrations in free-ranging animal populati ...202032577285
non-invasive assessment of body condition and stress-related fecal glucocorticoid metabolite concentrations in african elephants (loxodonta africana) roaming in fynbos vegetation.fynbos is a unique endemic vegetation type belonging to the cape floral kingdom in the western cape province of south africa, representing the smallest of the six floral kingdoms in the world. nowadays, only a few game reserves in this region support populations of african elephants (loxodonta africana), and thus, little information exists regarding the suitability of the nutritionally poor fynbos vegetation for these megaherbivores. using already established non-invasive methods, the monitoring ...202032397066
spatial geochemistry influences the home range of elephants.the unique geochemistry surrounding the palabora mining company (pmc) land may act as a micronutrient hotspot, attracting elephants to the area. the pmc produces refined copper and extracts phosphates and other minerals. understanding the spatial influence of geochemistry on the home range size of african elephants is important for elephant population management and conservation. the home ranges of collared elephants surrounding the pmc were significantly smaller (p = 0.001) than conspecifics in ...202032388134
characterizing the landscape of movement to identify critical wildlife habitat and corridors.landscape planning that ensures the ecological integrity of ecosystems is critical in the face of rapid human-driven habitat conversion and development pressure. wildlife tracking data provide unique and valuable information on animal distribution and location-specific behaviors that can serve to increase the efficacy of such planning. given the spatiotemporal complexity inherent to animal movements, the interaction between movement behavior and a location is often oversimplified in commonly app ...202032323365
understanding the drivers of mortality in african savannah elephants.populations of african savannah elephants (loxodonta africana) have been declining due to poaching, human-elephant conflict, and habitat loss. understanding the causes of these declines could aid in stabilizing elephant populations. we used data from the great elephant census, a 19-country aerial survey of savannah elephants conducted in 2014 and 2015, to examine effects of a suite of variables on elephant mortality. independent variables included spatially explicit measures of natural processes ...202032297403
understanding prolactin regulation and determining the efficacy of cabergoline and domperidone to mitigate prolactin-associated ovarian cycle problems in zoo african elephants (loxodonta africana ).perturbations in serum prolactin secretion, both over- and underproduction, are observed in zoo african elephants (loxodonta africana) that exhibit abnormal ovarian cycles. similar prolactin problems are associated with infertility in other species. pituitary prolactin is held under constant inhibition by a hypothalamic-derived neurotransmitter, dopamine; thus, regulation by exogenous treatment with agonists or antagonists may be capable of reinitiating normal ovarian cycles. this study tested t ...202032212542
diurnal variation of salivary cortisol in captive african elephants (loxodonta africana) under routine management conditions and in relation to a translocation event.the present study assessed the diurnal variation in salivary cortisol in captive african elephants during routine management (baseline) and in relation to a potential stressor (translocation) to evaluate to what extent acute stress may affect diurnal cortisol patterns. under baseline conditions, we collected morning and afternoon saliva samples of 10 animals (three zoos) on different days in two study periods (n = 3-10 per animal, daytime and period). under stress conditions, we sampled the tran ...202032134143
'remote' behavioural ecology: do megaherbivores consume vegetation in proportion to its presence in the landscape?examination of the feeding habits of mammalian species such as the african elephant (loxodonta africana) that range over large seasonally dynamic areas is exceptionally challenging using field-based methods alone. although much is known of their feeding preferences from field studies, conclusions, especially in relation to differing habits in wet and dry seasons, are often contradictory. here, two remote approaches, stable carbon isotope analysis and remote sensing, were combined to investigate ...202032117638
unilateral phacoemulsification in a captive african elephant (loxodonta africana).the following case reports describe the clinical presentation, surgical protocol, post-operative care, and long-term follow-up of an african elephant (loxodonta africana) presenting with a unilateral cataract.202032042648
sperm motility, kinematics, morphometry and morphology over two seasons in free-ranging african elephants (loxodonta africana).this study aimed to address the lack of information on quantitative semen and sperm characteristics of free-ranging african elephants. nineteen ejaculates were collected from 12 elephant bulls by means of electroejaculation in spring (season 1, end of dry season, n=7) and in autumn (season 2, end of rainy season, n=12). while most elephant cows are in oestrus in the rainy season, it is not evident whether sperm quality also improves during this period. semen samples were assessed using computer- ...202031972123
exploring movement decisions: can bayesian movement-state models explain crop consumption behaviour in elephants (loxodonta africana)?animal movements towards goals or targets are based upon either maximization of resource acquisition or risk avoidance, and the way animals move can reveal information about their motivation. we use hidden markov models (hmms) fitted in a bayesian framework and hourly global positioning system fixes to distinguish animal movements into distinct states and analyse the influence of environmental variables on being in, and switching to, a particular state. specifically, we apply our models to under ...202031960413
ixodid ticks (acari: ixodidae) collected from african savanna elephants (loxodonta africana) and african forest elephants (loxodonta cyclotis).eight ixodid tick species were collected from 173 african savanna elephants (loxodonta africana) in kenya, northern mozambique and zimbabwe, and two species were collected from six african forest elephants (loxodonta cyclotis) in the republic of congo. a new host record is reported for amblyomma eburneum. a list of ticks collected from elephants in various african countries, and stored in the united states national tick collection, is supplied as well as an annotated checklist of the 27 ixodid t ...201931714141
elephant behavior toward the dead: a review and insights from field observations.many nonhuman animals have been documented to take an interest in their dead. a few socially complex and cognitively advanced taxa-primates, cetaceans, and proboscideans-stand out for the range and duration of behaviors that they display at conspecific carcasses. here, we review the literature on field observations of elephants at carcasses to identify patterns in behaviors exhibited. we add to this literature by describing elephant responses to dead elephants in the samburu national reserve, no ...202031713106
analyses of african elephant (loxodonta africana) diet with various browse and pellet inclusion levels.to more closely simulate the diet of free-ranging elephants, the diet of six (2.4) african elephants (loxodonta africana) was altered to include more browse and less pelleted complete feed (5% total diet). dietary proximate compounds, minerals, vitamins a (and carotenoids), d and e, and fatty acids were analyzed on pelleted diet items and forages including hay, grass, and browse. a total of 42 browse species were offered over 1 year with an average total diet inclusion of 5.2% (dry matter basis) ...202031710122
soft and persistent-the influence of sand-flooring and calves on the resting behavior of a zoo-kept african elephant (loxodonta africana) group.caring for all aspects of zoo elephants' well-being is considered a major challenge. providing an appropriate flooring substrate to facilitate lying rest presents a meaningful part of a holistic management concept. investigating the impact of a new sand flooring on the nocturnal resting behavior of a breeding group of seven african elephants living at one zoo revealed more total lying rest, longer bouts of lying rest and a reduced side preference in the adult females. with an average total daily ...202031663179
conservation genetic assessment of savannah elephants (loxodonta africana) in the greater kruger biosphere, south africa.savannah elephant populations have been severely reduced and fragmented throughout its remaining range. in general, however, there is limited information regarding their genetic status, which is essential knowledge for conservation. we investigated patterns of genetic variation in savannah elephants from the greater kruger biosphere, with a focus on those in previously unstudied nature reserves adjacent to kruger national park, using dung samples from 294 individuals and 18 microsatellites. the ...201931590388
african elephant genetics: enigmas and anomalies.during the last two decades, our understanding of the genetics of african elephant populations has greatly increased. strong evidence, both morphological and genetic, supports recognition of two african elephant species: the savanna elephant (loxodonta africana) and the forest elephant (l. cyclotis). among elephantids, phylogeographic patterns for mitochondrial dna are highly incongruent with those detected using nuclear dna markers, and this incongruence is almost certainly due to strongly male ...201931544772
bilateral phacoemulsification in an african elephant (loxodonta africana).a 37-year-old bull african elephant (loxodonta africana) at the north carolina zoo (ncz) was diagnosed with bilateral cataracts leading to behavioral changes and significant weight loss secondary to functional blindness. on initial examination, a weight loss of 234 kg, a mature cataract in the right eye, and a focal cataract in the left eye were diagnosed. ultrasound and electroretinography (erg) indicated normal retinal attachment and both eyes were viable candidates for surgery. after careful ...201931380140
leveraging multidimensional heterogeneity in resource selection to define movement tactics of animals.increasing interest in the complexity, variation and drivers of movement-related behaviours promise new insight into fundamental components of ecology. resolving the multidimensionality of spatially explicit behaviour remains a challenge for investigating tactics and their relation to niche construction, but high-resolution movement data are providing unprecedented understanding of the diversity of spatially explicit behaviours. we introduce a framework for investigating individual variation in ...201931240840
movement reveals reproductive tactics in male elephants.long-term bio-logging has the potential to reveal how movements, and hence life-history trade-offs, vary over a lifetime. reproductive tactics in particular may vary as individuals' trade-off current investment versus lifetime fitness. male african savanna elephants (loxodona africana) provide a telling example of balancing body growth with reproductive fitness due to the combination of indeterminate growth and strongly delineated periods of sexual activity (musth), which results in reproductive ...202031236936
researching immunocontraceptive vaccines with mares (equus caballus) as both a target and model for african elephant (loxodonta africana) cows: a review.a sequence of studies is reviewed that reported the domestic horse (equus caballus) mare as an appropriate and accessible research platform for recording clinical and laboratory data post-immunisation with anti- gnrh and -zona pellucida (zp) immunocontraceptive vaccines. experience with a native porcine zp (pzp) vaccine in african elephant (loxodonta africana) cows highlighted needs for improving vaccine formulations and more clearly defining associated ovarian effects and safety profiles. initi ...201931208844
evidence of a growing elephant poaching problem in botswana.botswana holds roughly one-third of africa's remaining savannah elephants (loxodonta africana) [1, 2] and will play a key role in the future conservation of this species. to date, botswana has been one of the safest countries for elephants, with little poaching reported [3]. here, we present evidence of a new outbreak of elephant poaching for ivory in northern botswana. comparing results from 2014 and 2018 aerial surveys, we found that elephant populations were stable, but numbers of elephant ca ...201931204160
seroprevalence of mycobacterium tuberculosis complex in free-ranging african elephants (loxodonta africana) in kruger national park, south africa.tuberculosis (tb) is a pathogenic disease that affects a range of wildlife species, including african elephants (loxodonta africana). the recent discovery of fatal disease caused by infection with mycobacterium tuberculosis in a bull elephant in the kruger national park (knp), which is a bovine tb endemic area, emphasizes the importance this disease could have on both wild and captive elephant populations globally. elephants with culture-confirmed tb have previously been shown to produce strong ...201931166850
mining morphometrics and age from past survey photographs.researchers often document wildlife surveys using images. these images contain data that can be used to understand alterative research objectives, even years after they were originally captured. we have developed a method to measure age and morphology (body size measurements and tusk size) from survey image databases and future surveys, without the availability of a known subject distance or a scale in each image. african savanna elephants (loxodonta africana) serve as an ideal model species to ...201931114625
"keep your feet on the ground": simulated range of motion and hind foot posture of the middle jurassic sauropod rhoetosaurus brownei and its implications for sauropod biology.the biomechanics of the sauropod dinosaur pes is poorly understood, particularly among the earliest members of the group. to date, reasonably complete and articulated pedes in early middle jurassic sauropods are rare, limited to a handful of taxa. of these, rhoetosaurus brownei, from eastern australia, is currently the only one from the gondwanan middle jurassic that preserves an articulated pes. using rhoetosaurus brownei as a case exemplar, we assessed its paleobiomechanical capabilities and p ...201930964205
do topography and fruit presence influence occurrence and intensity of crop-raiding by forest elephants (loxodonta africana cyclotis)?crop damage by forest elephants (loxodonta africana cyclotis) and the resulting human-elephant conflict are issues of great concern for both the conservation of the species and the protection of rural livelihoods in central africa. addressing these problems requires identifying the factors that facilitate or impede crop-raiding by forest elephants. yet to date, the environmental or anthropogenic factors that influence the occurrence and intensity of crop-raiding by forest elephants are largely u ...201930901366
war-induced collapse and asymmetric recovery of large-mammal populations in gorongosa national park, mozambique.how do large-mammal communities reassemble after being pushed to the brink of extinction? few data are available to answer this question, as it is rarely possible to document both the decline and recovery of wildlife populations. here we present the first in-depth quantitative account of war-induced collapse and postwar recovery in a diverse assemblage of large herbivores. in mozambique's gorongosa national park, we assembled data from 15 aerial wildlife counts conducted before (1968-1972) and a ...201930865663
hyperprolactinemic african elephant (loxodonta africana) females exhibit elevated dopamine, oxytocin and serotonin concentrations compared to normal cycling and noncycling, low prolactin elephants†.many zoo elephants do not cycle normally, and for african elephants, it is often associated with hyperprolactinemia. dopamine agonists successfully treat hyperprolactinemia-induced ovarian dysfunction in women, but not elephants. the objective of this study was to determine how longitudinal dopamine, serotonin, and oxytocin patterns in african elephants are related to ovarian cycle function. we hypothesized that dopamine concentrations are decreased, while oxytocin and serotonin are increased in ...201930848798
determinants of elephant foraging behaviour in a coupled human-natural system: is brown the new green?crop raiding by wildlife poses major threats to both wildlife conservation and human well-being in agroecosystems worldwide. these threats are particularly acute in many parts of africa, where crop raiders include globally threatened megafauna such as elephants, and where smallholder agriculture is a primary source of human livelihood. one framework for understanding herbivore feeding behaviour, the forage-maturation hypothesis, predicts that herbivores should align their movements with intermed ...201930825191
mammoth ivory was the most suitable osseous raw material for the production of late pleistocene big game projectile points.late pleistocene societies throughout the northern hemisphere used mammoth and mastodon ivory not only for art and adornment, but also for tools, in particular projectile points. a comparative analysis of the mechanical properties of tusk dentine from woolly mammoth (mammuthus primigenius) and african elephant (loxodonta africana) reveals similar longitudinal stiffness values that are comparable to those of cervid antler compacta. the longitudinal bending strength and work of fracture of probosc ...201930783179
terrestrial mammalian wildlife responses to unmanned aerial systems approaches.unmanned aerial systems (uas) are increasingly being used recreationally, commercially and for wildlife research, but very few studies have quantified terrestrial mammalian reactions to uas approaches. we used two vertical take-off and landing (vtol) uas to approach seven herbivore species in the moremi game reserve, botswana, after securing the relevant permissions. we recorded responses to 103 vertical and 120 horizontal approaches, the latter from three altitudes above ground level (agl). we ...201930765800
african savanna elephants (loxodonta africana) as an example of a herbivore making movement choices based on nutritional needs.the increasing human population and global intensification of agriculture have had a major impact on the world's natural ecosystems and caused devastating effects on populations of mega-herbivores such as the african savanna elephants, through habitat reduction and fragmentation and increased human-animal conflict. animals with vast home ranges are forced into increasingly smaller geographical areas, often restricted by fencing or encroaching anthropogenic activities, resulting in huge pressures ...201930723615
locally-curved geometry generates bending cracks in the african elephant skin.an intricate network of crevices adorns the skin surface of the african bush elephant, loxodonta africana. these micrometre-wide channels enhance the effectiveness of thermal regulation (by water retention) as well as protection against parasites and intense solar radiation (by mud adherence). while the adaptive value of these structures is well established, their morphological characterisation and generative mechanism are unknown. using microscopy, computed tomography and a custom physics-based ...201830279508
field propagation experiments of male african savanna elephant rumbles: a focus on the transmission of formant frequencies.african savanna elephants live in dynamic fission⁻fusion societies and exhibit a sophisticated vocal communication system. their most frequent call-type is the 'rumble', with a fundamental frequency (which refers to the lowest vocal fold vibration rate when producing a vocalization) near or in the infrasonic range. rumbles are used in a wide variety of behavioral contexts, for short- and long-distance communication, and convey contextual and physical information. for example, maturity (age and s ...201830274350
milk composition of indian rhinoceros ( rhinoceros unicornis) and changes over lactation.the objective of this study was to determine the major nutrient composition of indian rhinoceros milk ( rhinoceros unicornis) over the first 13 mo of an 18-mo lactation period and to compare the results to those of previous studies on rhinoceros, african elephant ( loxodonta africana), and horse milk ( equus ferus caballus). the following parameters were measured: dry matter (dm), crude ash (ash), crude protein (cp), ether extract (ee), nitrogen-free extract (nfe; calculated), lactose, calcium ( ...201830212337
water for african elephants (loxodonta africana): faecal microbial loads affect use of artificial waterholes.in semi-arid protected areas, artificial waterholes ensure that water is locally available to animals for extended periods. however, artificial waterholes may limit animal movement, which contributes towards habitat deterioration. challenges of artificial water provisioning worsen in the presence of ecosystem engineers like african elephants loxodonta africana, capable of transforming environments. camera traps were used to monitor elephant visitation at 21 artificial waterholes in the kruger na ...201830158141
ixodid ticks of african buffalo (syncerus caffer), impala (aepyceros melampus) and elephant (loxodonta africana) in five protected park estates in the zambezi valley, zimbabwe.wildlife hosts many pathogens of economic importance and is considered as a reservoir of important tick-borne diseases of livestock in southern africa. the species composition of ticks parasitizing buffalo (syncerus caffer), impala (aepyceros melampus) and elephant (loxodonta africana) was investigated in five protected parks in the zambezi valley, zimbabwe. a total of 1104 adult ticks was collected from 75 adult animals comprising five buffaloes, five elephants and five impalas drawn from five ...201830088213
partial migration in savanna elephant populations distributed across southern africa.migration is an important, but threatened ecological process. conserving migration requires the maintenance of functional connectivity across sufficiently large areas. therefore, we need to know if, where and why species migrate. elephants are highly mobile and can travel long distances but we do not know if they migrate. here, we analysed the movement trajectories of 139 savanna elephants (loxodonta africana) within eight clusters of protected areas across southern africa to determine if elepha ...201830054547
african bush elephants respond to a honeybee alarm pheromone blend.we here report the responses of african bush elephants (loxodonta africana) to a crude approximation of the honeybee alarm pheromone blend. we show that the elephants had an avoidance response to the semiochemical blend. the use of honeybee alarm pheromones to manage elephant movements in a non-invasive manner, using natural cues to which elephants may have an evolved response, holds potential for development of new options for an integrated system for elephant movement management and protection ...201830040934
savanna elephants maintain homeothermy under african heat.to conserve body water, mammals may reduce evaporative water loss by storing heat, allowing core body temperature to rise more than usual during the day, and to fall more than usual during the cooler night, so demonstrating heterothermy. it has been proposed that elephants are heterothermic, but body temperature never has been measured in elephants over 24 h at environmental temperatures higher than body temperature, where elephants would have to rely on evaporative cooling to maintain homeother ...201830008137
surgical treatment of an umbilical hernia in a free-ranging sub-adult african elephant in samburu national reserve, kenya.a 10-year-old male african elephant (loxodonta africana) at samburu national reserve in northern kenya, weighing approximately 1,600 kg, presented with an umbilical hernia in october 2013. umbilical herniorrhaphy was carried out under field conditions. anesthesia was induced and maintained using etorphine hydrochloride for 3 hours during the surgery. this case report details both the surgical and anesthetic procedure carried out to correct the hernia, and the eventual successful recovery of the ...201530101103
structural analysis of covid-19 spike protein in recognizing the ace2 receptor of different mammalian species and its susceptibility to viral infection.the pandemic covid-19 was caused by a novel coronavirus-2 (sars-cov-2) that infects humans through the binding of glycosylated sars-cov-2 spike 2 protein to the glycosylated ace2 receptor. the spike 2 protein recognizes the n-terminal helices of the glycosylated metalloprotease domain in the human ace2 receptor. to understand the susceptibility of animals for infection and transmission, we did sequence and structure-based molecular interaction analysis of 16 ace2 receptors from different mammali ...202133552834
molecular characterization of encephalomyocarditis virus strains isolated from an african elephant and rats in a french zoo.in november 2013, a fatal encephalomyocarditis virus (emcv) case in a captive african elephant (loxodonta africana) occurred at the réserve africaine de sigean, a zoo in the south of france. here we report the molecular characterization of the emcv strains isolated from samples collected from the dead elephant and from 3 rats (rattus rattus) captured in the zoo at the same time. the emcv infection was confirmed by reverse-transcription real-time pcr (rt-rtpcr) and genome sequencing. complete gen ...202033292091
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