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reproductive health assessment of female elephants in north american zoos and association of husbandry practices with reproductive dysfunction in african elephants (loxodonta africana).as part of a multi-institutional study of zoo elephant welfare, we evaluated female elephants managed by zoos accredited by the association of zoos and aquariums and applied epidemiological methods to determine what factors in the zoo environment are associated with reproductive problems, including ovarian acyclicity and hyperprolactinemia. bi-weekly blood samples were collected from 95 african (loxodonta africana) and 75 asian (elephas maximus) (8-55 years of age) elephants over a 12-month peri ...201627416141
the days and nights of zoo elephants: using epidemiology to better understand stereotypic behavior of african elephants (loxodonta africana) and asian elephants (elephas maximus) in north american zoos.stereotypic behavior is an important indicator of compromised welfare. zoo elephants are documented to perform stereotypic behavior, but the factors that contribute to performance have not been systematically assessed. we collected behavioral data on 89 elephants (47 african [loxodonta africana], 42 asian [elephas maximus]) at 39 north american zoos during the summer and winter. elephants were videoed for a median of 12 daytime hours per season. a subset of 32 elephants (19 african, 13 asian) wa ...201627416071
housing and demographic risk factors impacting foot and musculoskeletal health in african elephants [loxodonta africana] and asian elephants [elephas maximus] in north american zoos.for more than three decades, foot and musculoskeletal conditions have been documented among both asian [elephas maximus] and african [loxodonta africana] elephants in zoos. although environmental factors have been hypothesized to play a contributing role in the development of foot and musculoskeletal pathology, there is a paucity of evidence-based research assessing risk. we investigated the associations between foot and musculoskeletal health conditions with demographic characteristics, space, ...201627415763
assessment of body condition in african (loxodonta africana) and asian (elephas maximus) elephants in north american zoos and management practices associated with high body condition scores.obesity has a negative effect on health and welfare of many species, and has been speculated to be a problem for zoo elephants. to address this concern, we assessed the body condition of 240 elephants housed in north american zoos based on a set of standardized photographs using a 5-point body condition score index (1 = thinnest; 5 = fattest). a multi-variable regression analysis was then used to determine how demographic, management, housing, and social factors were associated with an elevated ...201627415629
evaluation of demographics and social life events of asian (elephas maximus) and african elephants (loxodonta africana) in north american zoos.this study quantified social life events hypothesized to affect the welfare of zoo african and asian elephants, focusing on animals that were part of a large multi-disciplinary, multi-institutional elephant welfare study in north america. age was calculated based on recorded birth dates and an age-based account of life event data for each elephant was compiled. these event histories included facility transfers, births and deaths of offspring, and births and deaths of non-offspring herd mates. ea ...201627415437
recumbence behavior in zoo elephants: determination of patterns and frequency of recumbent rest and associated environmental and social factors.resting behaviors are an essential component of animal welfare but have received little attention in zoological research. african savanna elephant (loxodonta africana) and asian elephant (elephas maximus) rest includes recumbent postures, but no large-scale investigation of african and asian zoo elephant recumbence has been previously conducted. we used anklets equipped with accelerometers to measure recumbence in 72 adult female african (n = 44) and asian (n = 28) elephants housed in 40 north a ...201627414809
elephant management in north american zoos: environmental enrichment, feeding, exercise, and training.the management of african (loxodonta africana) and asian (elephas maximus) elephants in zoos involves a range of practices including feeding, exercise, training, and environmental enrichment. these practices are necessary to meet the elephants' nutritional, healthcare, and husbandry needs. however, these practices are not standardized, resulting in likely variation among zoos as well as differences in the way they are applied to individual elephants within a zoo. to characterize elephant managem ...201627414654
determining connections between the daily lives of zoo elephants and their welfare: an epidemiological approach.concerns about animal welfare increasingly shape people's views about the acceptability of keeping animals for food production, biomedical research, and in zoos. the field of animal welfare science has developed over the past 50 years as a method of investigating these concerns via research that assesses how living in human-controlled environments influences the behavior, health and affective states of animals. initially, animal welfare research focused on animals in agricultural settings, but t ...201627414416
housing and social environments of african (loxodonta africana) and asian (elephas maximus) elephants in north american zoos.we evaluated 255 african (loxodonta africana) and asian (elephas maximus) elephants living in 68 north american zoos over one year to quantify housing and social variables. all parameters were quantified for the both the day and the night and comparisons were made across these time periods as well as by species and sex. to assess housing, we evaluated not only total exhibit size, but also individual animals' experiences based on the time they spent in the unique environments into which the exhib ...201627414034
review of elephant endotheliotropic herpesviruses and acute hemorrhagic disease.more than 100 young captive and wild asian elephants are known to have died from a rapid-onset, acute hemorrhagic disease caused primarily by multiple distinct strains of two closely related chimeric variants of a novel herpesvirus species designated elephant endotheliotropic herpesvirus (eehv1a and eehv1b). these and two other species of probosciviruses (eehv4 and eehv5) are evidently ancient and likely nearly ubiquitous asymptomatic infections of adult asian elephants worldwide that are occasi ...201626912715
comparative sequence analyses of genome and transcriptome reveal novel transcripts and variants in the asian elephant elephas maximus.the asian elephant elephas maximus and the african elephant loxodonta africana that diverged 5-7 million years ago exhibit differences in their physiology, behaviour and morphology. a comparative genomics approach would be useful and necessary for evolutionary and functional genetic studies of elephants. we performed sequencing of e. maximus and map to l. africana at ~15x coverage. through comparative sequence analyses, we have identified asian elephant specific homozygous, non-synonymous single ...201526648035
assessment of flooring renovations on african elephant (loxodonta africana) behavior and glucocorticoid response.captive african (loxodonta africana) and asian (elephas maximus) elephants can experience foot pathologies and arthritis. as a preventative measure against these pathologies and to alleviate the potential discomfort due to concrete substrates, some zoological institutions have renovated elephant housing to increase the amount of natural or shock-absorbent substrates. the objective of this study was to compare behavioral (diurnal and nocturnal) and glucorticoid (e.g., serum cortisol) responses of ...201526535582
elephant natural history: a genomic perspective.we review dna-based studies of elephants and recently extinct proboscideans. the evidence indicates that little or no nuclear gene flow occurs between african savanna elephants (loxodonta africana) and african forest elephants (loxodonta cyclotis), establishing that they comprise separate species. in all elephant species, males disperse, whereas females remain with their natal social group, leading to discordance in the phylogeography of nuclear and mitochondrial dna patterns. improvements in an ...201525493538
supression of testicular function in a male asian elephant (elephas maximus) treated with gonadotropin-releasing hormone vaccines.the ability to control testosterone concentrations and sperm production is of great interest in both asian (elephas maximus) and african (loxodonta africana) elephants. gnrh vaccination may pose an alternative to surgical castration. this is a case report of a male asian elephant treated with two commercial gnrh vaccines (equity and improvac). beginning at the age of 7 yr, the male was vaccinated monthly for 6 consecutive months, then every 6 mo and, finally, every 12 to 24 mo over a period of 6 ...201425314829
vocal learning in elephants: neural bases and adaptive context.in the last decade clear evidence has accumulated that elephants are capable of vocal production learning. examples of vocal imitation are documented in african (loxodonta africana) and asian (elephas maximus) elephants, but little is known about the function of vocal learning within the natural communication systems of either species. we are also just starting to identify the neural basis of elephant vocalizations. the african elephant diencephalon and brainstem possess specializations related ...201425062469
low coverage sequencing of two asian elephant (elephas maximus) genomes.there are three species of elephant that exist, the asian elephant (elephas maximus) and two species of african elephant (loxodonta africana and loxodonta cyclotis). the populations of all three species are dwindling, and are under threat due to factors, such as habitat destruction and ivory hunting. the species differ in many respects, including in their morphology and response to disease. the availability of elephant genome sequence data from all three elephant species will complement studies ...201425053995
fine-scale genetic structure and cryptic associations reveal evidence of kin-based sociality in the african forest elephant.spatial patterns of relatedness within animal populations are important in the evolution of mating and social systems, and have the potential to reveal information on species that are difficult to observe in the wild. this study examines the fine-scale genetic structure and connectivity of groups within african forest elephants, loxodonta cyclotis, which are often difficult to observe due to forest habitat. we tested the hypothesis that genetic similarity will decline with increasing geographic ...201424505381
detection of elephant endotheliotropic herpesvirus infection among healthy asian elephants (elephas maximus) in south india.elephant endotheliotropic herpesviruses (eehvs) can cause fatal hemorrhagic disease in asian (elephas maximus) and african (loxodonta africana) elephants. of the seven known eehv species, eehv1 is recognized as the most common cause of hemorrhagic disease among asian elephants in human care worldwide. recent data collected from ex situ asian elephants located in multiple north american and european institutions suggest that subclinical eehv1 infection is common in this population of elephants. a ...201424484479
effect of calcium and cholecalciferol supplementation on several parameters of calcium status in plasma and urine of captive asian (elephas maximus) and african elephants (loxodonta africana).the aim of the current study was to assess the effect of oral calcium and cholecalciferol supplementation on several parameters of calcium status in plasma and urine of captive asian (elephas maximus; n=10) and african elephants (loxodonta africana; n=6) and to detect potential species differences. calcium and cholecalciferol supplementation were investigated in a feeding trial using a crossover design consisting of five periods of 28 days each in summer. from days 28-56 (period 2), elephants we ...201324063079
climate influences thermal balance and water use in african and asian elephants: physiology can predict drivers of elephant distribution.elephant movement patterns in relation to surface water demonstrate that they are a water-dependent species. thus, there has been interest in using surface water management to mitigate problems associated with localized elephant overabundance. however, the physiological mechanisms underlying the elephant's water dependence remain unclear. although thermoregulation is likely an important driver, the relationship between thermoregulation, water use and climate has not been quantified. we measured ...201323842629
prenatal passive transfer of maternal immunity in asian elephants (elephas maximus).asian (elephas maximus) and african (loxodonta africana) elephants exhibit characteristics of endotheliochorial placentation, which is common in carnivore species and is associated with modest maternal to fetal transplacental antibody transfer. however, it remains unknown whether the bulk of passive immune transfer in elephants is achieved prenatally or postnatally through ingestion of colostrum, as has been documented for horses, a species whose medical knowledgebase is often extrapolated for e ...201323582266
fatal herpesvirus hemorrhagic disease in wild and orphan asian elephants in southern india.up to 65% of deaths of young asian elephants (elephas maximus) between 3 mo and 15 yr of age in europe and north america over the past 20 yr have been attributed to hemorrhagic disease associated with a novel dna virus called elephant endotheliotropic herpesvirus (eehv). to evaluate the potential role of eehv in suspected cases of a similar lethal acute hemorrhagic disease occurring in southern india, we studied pathologic tissue samples collected from field necropsies. nine cases among both orp ...201323568914
sperm dna fragmentation and morphological degeneration in chilled elephant (elephas maximus and loxodonta africana) semen collected by transrectal massage.ejaculates from nine asian and two african elephants were analysed to gain a further understanding of mechanisms underlying variable semen quality after transrectal massage. semen analysis was performed after collection (0 h; subjective motility parameters only) and after 24 h of chilled storage at 10 °c (24 h; all ejaculate and sperm characteristics). ejaculates with ≤50% total motility (tm) at 24 h, which represented >90% of collection attempts, contained a sperm population with a high degree ...201323536498
strangulating intestinal obstructions in four captive elephants (elephas maximus and loxodonta africana).three captive-born (5-day-old, 8-day-old, and 4-yr-old) asian elephants (elephas maximus) and one captive-born 22-yr-old african elephant (loxodonta africana) from three private elephant facilities and one zoo in the united states presented with depression, anorexia, and tachycardia as well as gastrointestinal signs of disease including abdominal distention, decreased borborygmi, tenesmus, hematochezia, or diarrhea. all elephants showed some evidence of discomfort including agitation, vocalizati ...201222448519
real-time pcr detection and quantification of elephantid dna: species identification for highly processed samples associated with the ivory trade.the ivory industry is the single most serious threat to global elephant populations. a highly sensitive, species-specific real-time pcr assay has been developed to detect and quantify african elephant (loxodonta africana), asian elephant (elephas maximus) and woolly mammoth (mammuthus primigenius) mitochondrial dna from highly processed samples involved in the international ivory trade. this assay is especially useful for highly processed samples where there are no distinguishing morphological f ...201222257967
chemosensory responses in two species of elephants to constituents of temporal gland secretion and musth urine.this report discusses three areas of investigation: (1) the chemical components in the temporal gland secretion (tgs) of asian (elephas maximus) and african (loxodonta africana) elephants were characterized by radioimmunoassay (ria) for testosterone (t) and dihydrotestosterone (dht) levels and by on-column capillary column gas chromatographic analysis of volatiles. an inverse relationship between tgs testosterone levels and (e)-farnesol levels was observed. (2). african elephants responded prefe ...198824276499
the social structure and strategies of delphinids: predictions based on an ecological framework.dolphins live in complex social groupings with a wide variety of social strategies. in this chapter we investigate the role that differing habitats and ecological conditions have played in the evolution of delphinid social strategies. we propose a conceptual framework for understanding natural patterns of delphinid social structure in which the spatial and temporal predictability of resources influences the ranging patterns of individuals and communities. the framework predicts that when resourc ...200717936137
choniagnium algericum sp. n. (nematoda: strongylidae) from the intestine of african elephant, loxodonta africana (blumenbach, 1779).nematodes of the genus choniagnium were found in african elephant (loxodonta africana) from algerian zoological garden. on the basis of studies in light and scanning electron microscope these nematodes were identified as a new species, choniagnium algericum sp. n.19836662405
interspecific interference competition at the resource patch scale: do large herbivores spatially avoid elephants while accessing water?animals may anticipate and try to avoid, at some costs, physical encounters with other competitors. this may ultimately impact their foraging distribution and intake rates. such cryptic interference competition is difficult to measure in the field, and extremely little is known at the interspecific level. we tested the hypothesis that smaller species avoid larger ones because of potential costs of interference competition and hence expected them to segregate from larger competitors at the scale ...201627495127
a comparison of zoo animal behavior in the presence of familiar and unfamiliar people.as recorded in domestic nonhuman animals, regular interactions between animals in zoos and keepers and the resulting relationship formed (human-animal relationship [har]) are likely to influence the animals' behaviors with associated welfare consequences. har formation requires that zoo animals distinguish between familiar and unfamiliar people. this ability was tested by comparing zoo animal behavioral responses to familiar (routine) keepers and unfamiliar keepers (participants in the "keeper f ...201626960022
neocortical neuronal morphology in the newborn giraffe (giraffa camelopardalis tippelskirchi) and african elephant (loxodonta africana).although neocortical neuronal morphology has been documented in the adult giraffe (giraffa camelopardalis tippelskirchi) and african elephant (loxodonta africana), no research has explored the cortical architecture in newborns of these species. to this end, the current study examined the morphology of neurons from several cortical areas in the newborn giraffe and elephant. after cortical neurons were stained with a modified golgi technique (n = 153), dendritic branching and spine distributions w ...201626104263
comparative anatomy of the ciliary body of the west indian manatee (trichechus manatus) and selected species.to examine the anatomy of the ciliary body in the west indian manatee (trichechus manatus), paying close attention to its vascularization and to compare to those of its distant relative, the african elephant (loxodonta africana), the amphibious hippopotamus (hippopotamus amphibius) and the aquatic short-finned pilot whale (globicephala macrorhynchus).200616359360
structure and presumptive function of the iridocorneal angle of the west indian manatee (trichechus manatus), short-finned pilot whale (globicephala macrorhynchus), hippopotamus (hippopotamus amphibius), and african elephant (loxodonta africana).the iridocorneal angles of prepared eyes from the west indian manatee, short-finned pilot whale, hippopotamus and african elephant were examined and compared using light microscopy. the manatee and pilot whale demonstrated capacity for a large amount of aqueous outflow, probably as part of a system compensating for lack of ciliary musculature, and possibly also related to environmental changes associated with life at varying depths. the elephant angle displayed many characteristics of large herb ...200312641841
african elephant myoglobin with an unusual autoxidation behavior: comparison with the h64q mutant of sperm whale myoglobin.elephant myoglobins both from asian and african species have a glutamine in place of the usual distal (e7) histidine at position 64. we have isolated native oxymyoglobin directly from the skeletal muscle of african elephant (loxodonta africana), and examined the autoxidation rate of oxymyoglobin (mbo2) to metmyoglobin (metmb) as a function of ph in 0.1 m buffer at 25 degreesc. as a result, african elephant mbo2 was found to be equally resistant to autoxidation as sperm whale myoglobin. however, ...19989748556
streptococcus agalactiae in elephants - a comparative study with isolates from human and zoo animal and livestock origin.streptococcus (s.) agalactiae represents a significant pathogen for humans and animals. however, there are only a few elderly reports on s. agalactiae infections in wild and zoo elephants even though this pathogen has been isolated comparatively frequently in these endangered animal species. consequently, between 2004 and 2015, we collected s. agalactiae isolates from african and asian elephants (n=23) living in four different zoos in germany. these isolates were characterised and compared with ...201728532793
understanding tourists' preference for mammal species in private protected areas: is there a case for extralimital species for ecotourism?private protected areas (ppas) often use wildlife-based ecotourism as their primary means of generating business. achieving tourist satisfaction has become a strong driving goal in the management of many ppas, often at the expense of biodiversity. many extralimitral species, those which historically did not occur in an area, are stocked in ppas with the intention of increasing ecotourism attractions. even though the ecological and economic costs of stocking these species are high, the social ben ...201424505426
trophy hunting and sustainability: temporal dynamics in trophy quality and harvesting patterns of wild herbivores in a tropical semi-arid savanna ecosystem.the selective nature of trophy hunting may cause changes in desirable phenotypic traits in harvested species. a decline in trophy size of preferred species may reduce hunting destination competitiveness thus compromising the sustainability of trophy hunting as a conservation tool. we explored the trophy quality and trends in harvesting patterns (i.e., 2004-2015) of cape buffalo (syncerus caffer), african elephant (loxodonta africana), greater kudu (tragelaphus strepsiceros) and sable (hippotragu ...201627736930
characterization of mucus glycoproteins in the intestinal mucosa of the african elephant (loxodonta africana) following lectin histochemistry.the glycoproteins of the small intestines, caecum and colon of three adult elephants and one recently weaned elephant calf were examined by means of lectin histochemistry. tissue sections were histochemically stained with peroxidase-labelled concanavalin a (con a), asparagus-pea (tpa), peanut (pna) and wheat-germ (wga) lectins. con a and tpa showed no binding activity in the intestinal tract of the adult elephants or the duodenum and ileum of the elephant calf, but did show a small amount of bin ...19958628572
discovery of alpha-defensins in basal mammals.alpha-defensins are essential molecules of the innate immune system that have broad spectrum antimicrobial activity against a range of bacteria and viruses. to date, alpha-defensins have only been identified in the euarchontoglires branch of the mammals. this has led to speculation that alpha-defensins may be specific to this group, a somewhat surprising finding, given their importance in the immune system. the mammalian genome project provided us with the opportunity to search for alpha-defensi ...200717367857
monitoring and controlling ovarian activity in elephants.both asian (elephas maximus) and african (loxodonta africana) elephants are important keystone, umbrella and flagship species. paradoxically, world population numbers of both species are declining in many of their natural ranges due mainly to poaching, while over population of elephants in some areas is resulting in serious human-elephant conflict, and modifications of natural habitats that impact biodiversity. understanding mechanisms of reproductive control is vital to effective population man ...201729287954
being stressed outside the park-conservation of african elephants (loxodonta africana)in namibia.the conservation of the african savanna elephant (loxodonta africana) is of prime importance for many african countries. interactions between elephants and humans are known to induce stress and thereby have the potential to affect elephants' fitness. in namibia, anthropogenic disturbances are increasing due to increasing human population size and development, particularly near protected areas, such as national parks. in this study, we investigated elephant stress levels in relation to their land ...201729270294
tuberculosis serosurveillance and management practices of captive african elephants (loxodonta africana) in the kavango-zambezi transfrontier conservation area.transfrontier conservation areas represent an international effort to encourage conservation and sustainable development. their success faces a number of challenges, including disease management in wildlife, livestock and humans. tuberculosis (tb) affects humans and a multitude of non-human animal species and is of particular concern in sub-saharan africa. the kavango-zambezi transfrontier conservation area encompasses five countries, including zimbabwe, and is home to the largest contiguous pop ...201729143466
elephant-initiated interactions with humans: individual differences and specific preferences in captive african elephants (loxodonta africana).south africa has seen a recent increase in the number of african elephants (loxodonta africana) maintained in reserves and parks and managed in free contact, where they may spend a significant amount of time in close proximity to humans. this study investigates how individual elephants choose to initiate interactions with humans by examining whether interaction types and frequencies vary both between elephants and with regards to the category of human involved in the interaction. observations we ...201728503553
the influence of socioeconomic factors on the densities of high-value cross-border species, the african elephant.unprecedented poaching levels triggered by demand for ivory in far east asia are threatening the persistence of african elephantloxodonta africana. southern african countries make an important contribution to elephant conservation and could soon become the last stronghold of elephant conservation in africa. while the ecological factors affecting elephant distribution and densities have extensively been accounted for, there is a need to understand which socioeconomic factors affect elephant numbe ...201627812404
comadre: a global data base of animal demography.the open-data scientific philosophy is being widely adopted and proving to promote considerable progress in ecology and evolution. open-data global data bases now exist on animal migration, species distribution, conservation status, etc. however, a gap exists for data on population dynamics spanning the rich diversity of the animal kingdom world-wide. this information is fundamental to our understanding of the conditions that have shaped variation in animal life histories and their relationships ...201626814420
towards an automated acoustic detection system for free ranging elephants.the human-elephant conflict is one of the most serious conservation problems in asia and africa today. the involuntary confrontation of humans and elephants claims the lives of many animals and humans every year. a promising approach to alleviate this conflict is the development of an acoustic early warning system. such a system requires the robust automated detection of elephant vocalizations under unconstrained field conditions. today, no system exists that fulfills these requirements. in this ...201825983398
interpretation of human pointing by african elephants: generalisation and rationality.factors influencing the abilities of different animals to use cooperative social cues from humans are still unclear, in spite of long-standing interest in the topic. one of the few species that have been found successful at using human pointing is the african elephant (loxodonta africana); despite few opportunities for learning about pointing, elephants follow a pointing gesture in an object-choice task, even when the pointing signal and experimenter's body position are in conflict, and when the ...201424942107
elephants can determine ethnicity, gender, and age from acoustic cues in human voices.animals can accrue direct fitness benefits by accurately classifying predatory threat according to the species of predator and the magnitude of risk associated with an encounter. human predators present a particularly interesting cognitive challenge, as it is typically the case that different human subgroups pose radically different levels of danger to animals living around them. although a number of prey species have proved able to discriminate between certain human categories on the basis of v ...201424616492
detusking fence-breaker elephants as an approach in human-elephant conflict mitigation.human-elephant conflict (hec) is a recurring problem that appears wherever the range of elephants and humans overlap. different methods including the use of electric fences are used worldwide to mitigate this conflict. nonetheless, elephants learn quickly that their tusks do not conduct electricity and use them to break down fences (fence-breakers).201424614538
organization and chemical neuroanatomy of the african elephant (loxodonta africana) hippocampus.elephants are thought to possess excellent long-term spatial-temporal and social memory, both memory types being at least in part hippocampus dependent. although the hippocampus has been extensively studied in common laboratory mammalian species and humans, much less is known about comparative hippocampal neuroanatomy, and specifically that of the elephant. moreover, the data available regarding hippocampal size of the elephant are inconsistent. the aim of the current study was to re-examine hip ...201423728481
the social and ecological integration of captive-raised adolescent male african elephants (loxodonta africana) into a wild population.a rapid rise in the number of captive african elephants (loxodonta africana) used in the tourism industry in southern africa and orphaned elephants in human care has led to concerns about their long-term management, particularly males. one solution is to release them into the wild at adolescence, when young males naturally leave their herd. however, this raises significant welfare concerns: little is known about how well released elephants integrate into wild populations and whether they pose a ...201323437076
comparative demography of an at-risk african elephant population.knowledge of population processes across various ecological and management settings offers important insights for species conservation and life history. in regard to its ecological role, charisma and threats from human impacts, african elephants are of high conservation concern and, as a result, are the focus of numerous studies across various contexts. here, demographic data from an individually based study of 934 african elephants in samburu, kenya were summarized, providing detailed inspectio ...201323341984
putting the elephant back in the herd: elephant relative quantity judgments match those of other species.the ability to discriminate between quantities has been observed in many species. typically, when an animal is given a choice between two sets of food, accurate performance (i.e., choosing the larger amount) decreases as the ratio between two quantities increases. a recent study reported that elephants did not exhibit ratio effects, suggesting that elephants may process quantitative information in a qualitatively different way from all other nonhuman species that have been tested (irie-sugimoto ...201222692435
molecular characterization of adipose tissue in the african elephant (loxodonta africana).adipose tissue (at) is a dynamic and flexible organ with regulatory roles in physiological functions including metabolism, reproduction and inflammation; secreted adipokines, including leptin, and fatty acids facilitate many of these roles. the african elephant (loxodonta africana) is experiencing serious challenges to optimal reproduction in captivity. the physiological and molecular basis of this impaired fertility remains unknown. at production of leptin is a crucial molecular link between nu ...201424633017
the developing renal, reproductive, and respiratory systems of the african elephant suggest an aquatic ancestry.the early embryology of the elephant has never been studied before. we have obtained a rare series of african elephant (loxodonta africana) embryos and fetuses ranging in weight from 0.04 to 18.5 g, estimated gestational ages 58-166 days (duration of gestation is approximately 660 days). nephrostomes, a feature of aquatic vertebrates, were found in the mesonephric kidneys at all stages of development whereas they have never been recorded in the mesonephric kidneys of other viviparous mammals. th ...199910318922
prolactin in the afrotheria: characterization of genes encoding prolactin in elephant (loxodonta africana), hyrax (procavia capensis) and tenrec (echinops telfairi).pituitary prolactin shows an episodic pattern of molecular evolution, with occasional short bursts of rapid change imposed on a generally rather slow evolutionary rate. in mammals, episodes of rapid change occurred in the evolution of primates, cetartiodactyls, rodents and the elephant. the bursts of rapid evolution in cetartiodactyls and rodents were followed by duplications of the prolactin gene that gave rise to large families of prolactin-related proteins including placental lactogens, while ...200919017712
wild sri lankan elephants retreat from the sound of disturbed asian honey bees.asian elephants (elephas maximus) are threatened primarily by habitat loss and human-elephant conflict. in addition to establishing protected areas and corridors for wildlife, empowering farmers to protect their crops is crucial for asian elephant conservation [1,2]. elephants can habituate to artificial deterrents, hence natural biological alternatives are of great interest [2,3]. african elephants (loxodonta africana) avoid african honey bees (apis mellifera scutellata), inspiring 'beehive fen ...201829374444
metabolic health assessment of zoo elephants: management factors predicting leptin levels and the glucose-to-insulin ratio and their associations with health parameters.screening for metabolic-related health problems can enhance animal welfare, so the purpose of this study was to conduct the first metabolic health assessment of zoo elephants and use epidemiological methods to determine how factors in the captive environment were associated with metabolic hormone concentrations. in addition, we examined relationships between metabolic status and several fitness parameters: foot health, musculoskeletal health, reproductive cyclicity, and body condition. two blood ...201729186207
first report of changes in leukocyte morphology in response to inflammatory conditions in asian and african elephants (elephas maximus and loxodonta africana).although the hematology of healthy elephants has been well-described, published information on hematological changes during disease is limited. the objective of this study was to describe qualitative morphological changes in the leukocytes of asian and african elephants (elephas maximus and loxodonta africana) diagnosed with a variety of inflammatory conditions. twenty-five of 27 elephants had morphological changes in their leukocytes, although only 16 of these had a concurrent inflammatory leuk ...201728934325
use of composite materials as a component of tusk fracture management in an asian elephant (elephas maximus) and an african elephant (loxodonta africana).tusk fractures in asian (elephas maximus) and african elephants (loxodonta africana) can result in damage to the distal end or to longitudinal cracks, potentially progressing to pulpitis. with pulp exposure, endodontic therapy is the treatment of choice, but conservative therapy has sufficed for some elephants. this manuscript describes the use of composite materials as a component of tusk fracture management. a 7-yr-old male asian elephant fractured the distal end of both tusks with pulp exposu ...201728920780
foot pressure distributions during walking in african elephants (loxodonta africana).elephants, the largest living land mammals, have evolved a specialized foot morphology to help reduce locomotor pressures while supporting their large body mass. peak pressures that could cause tissue damage are mitigated passively by the anatomy of elephants' feet, yet this mechanism does not seem to work well for some captive animals. this study tests how foot pressures vary among african and asian elephants from habitats where natural substrates predominate but where foot care protocols diffe ...201627853539
freezing african elephant semen as a new population management tool.the captive elephant population is not self-sustaining and with a limited number of breeding bulls, its genetic diversity is in decline. one way to overcome this is to import young and healthy animals from the wild. we introduce here a more sustainable alternative method - importation of semen from wild bulls without removing them from their natural habitat. due to the logistics involved, the only practical option would be to transport cryopreserved sperm. despite some early reports on african e ...201323483917
elephants have relatively the largest cerebellum size of mammals.the current study used mr imaging to determine the volume of the cerebellum and its component parts in the brain of three adult male african elephants (loxodonta africana) and compared this with published data from asian elephants and other mammalian species including odontocete cetaceans, primates, chiropterans, insectivores, carnivores, and artiodactyls. the cerebellum of the adult elephant has a volume of ∼925 ml (average of both african and asian species). allometric analysis indicates that ...201222282440
insect pheromones and precursors in female african elephant urine.using automated solid-phase dynamic extraction and gas chromatography-mass spectrometry, our search for urinary chemical signals from ovulatory female african elephants (loxodonta africana) has revealed the bark beetle aggregation pheromones frontalin, exo-brevicomin, and endo-brevicomin, as well as their precursors and the aphid alarm pheromones (e,e)-alpha-farnesene and (e)-beta-farnesene. enantiomeric ratios for brevicomins have been determined. prior discovery of common insect/elephant phero ...200616758337
hippopotamus (h. amphibius) diet change indicates herbaceous plant encroachment following megaherbivore population collapse.megaherbivores (>1000 kg) are critical for ecosystem health and function, but face population collapse and extinction globally. the future of these megaherbivore-impoverished ecosystems is difficult to predict, though many studies have demonstrated increasing representation of c3 woody plants. these studies rely on direct observational data, however, and tools for assessing decadal-scale changes in african ecology without observation are lacking. we use isotopic records of historical common hipp ...201627616433
muscles and fascial elements of the antebrachium and manus of the african elephant (loxodonta africana, blumenbach 1797): starring comparative and functional considerations.the structure of the limbs of elephants is unusual among mammals. in african elephants (loxodonta africana, blumenbach 1797), the front limbs serve to support the greatest part of the body mass of the largest land animal. in this study, we present new and detailed anatomical data regarding muscular and specific fascial structures of the lower front limb which were examined by means of standard anatomical and histological techniques. the muscles and tendons of the forearm (antebrachium) and hand ...201829460451
applying network theory to animal movements to identify properties of landscape space use.network (graph) theory is a popular analytical framework to characterize the structure and dynamics among discrete objects, particularly effective at identifying critical hubs and patterns of connectivity. the identification of such attributes is a fundamental objective of animal movement research, yet network theory has rarely been applied directly to animal relocation data. we develop an approach that allows the analysis of movement data using network theory by defining occupied pixels as node ...201829420867
erratum: being stressed outside the park-conservation of african elephants (loxodonta africana)in namibia.[this corrects the article doi: 10.1093/conphys/cox067.][this corrects the article doi: 10.1093/conphys/cox067.].201829384530
megafaunal effects on vegetation structure throughout a densely wooded african landscape.megafauna strongly affect vegetation structure and composition, often leading to management concern. however, the extent of their influence across large scales and varying ecosystems remains largely unknown. using high resolution airborne light detection and ranging (lidar), we investigated landscape-scale changes in vegetation height and three-dimensional (3d) structure across landscapes of varying elephant densities and presence over time, and in response to surface water distribution and terr ...201829178395
nuclear organization of the african elephant (loxodonta africana) amygdaloid complex: an unusual mammalian amygdala.here we describe the nuclear organization of the african elephant amygdaloid complex using nissl, myelin, and a range of immunohistochemical stains. the african elephant is thought to exhibit many affect-laden and social-empathic behaviours; however, to date the amygdaloid complex, which is the generator of emotional states of the brain is yet to be fully explored in the elephants. for the most part, the amygdaloid complex of the african elephant is similar to that observed in other mammals in t ...201729098403
dust-bathing behaviors of african herbivores and the potential risk of inhalational anthrax.:  anthrax in herbivorous wildlife and livestock is generally assumed to be transmitted via ingestion or inhalation of bacillus anthracis spores. although recent studies have highlighted the importance of the ingestion route for anthrax transmission, little is known about the inhalational route in natural systems. dust bathing could aerosolize soilborne pathogens such as b. anthracis, exposing dust-bathing individuals to inhalational infections. we investigated the potential role of dust bathing ...201829053428
distances between individuals in an artificial herd of african elephants (loxodonta africana africana) during resource utilisation in a semi-captive environment.space allowance and resource dispersion is recognised as an important factor affecting the welfare of elephants in captivity. in the present pilot study, we investigated distances kept among individuals in an artificially created semi-captive mixed-sex group of african elephants, when individuals were free to disperse. the study involved a herd of six elephants, three females (aged 11 to 16years), and three males (aged 15 to 23years). they were observed through instantaneous scan sampling in ord ...201728942338
effects of gnrh vaccination in wild and captive african elephant bulls (loxodonta africana) on reproductive organs and semen quality.although the african elephant (loxodonta africana) is classified as endangered by the international union for conservation of nature (iucn), in some isolated habitats in southern africa, contraception is of major interest due to local overpopulation. gnrh vaccination has been promoted as a non-invasive contraceptive measure for population management of overabundant wildlife. we tested the efficacy of this treatment for fertility control in elephant bulls.201728915245
successful treatment of digital osteitis by intravenous regional perfusion of ceftiofur in an african elephant (loxodonta africana).a 41-yr-old african elephant ( loxodonta africana ) presented with a swollen third digit of the left forelimb and a 2-cm hole in the pad. corrective trimming, topical treatments, and an oral antibiotic resulted in apparent resolution; however, it reoccurred after 4 mo. radiographs suggested bone lysis in the third phalanx, with the primary differential diagnosis being septic osteitis. flushing with metronidazole solution and intravenous regional perfusion (ivrp) of the foot were commenced. a tou ...201728749306
epidemiologic evaluation of elephant endotheliotropic herpesvirus 3b infection in an african elephant (loxodonta africana).this epidemiologic study follows a 5-yr-old male african elephant ( loxodonta africana ) during an episode of hemorrhagic disease (hd) due to elephant endotheliotropic herpesvirus 3b (eehv3b) utilizing data from complete blood counts, electrophoresis and acute phase protein analysis, and polymerase chain reaction (pcr) of multiple body fluids during and after the clinical episode. the elephant presented with sudden onset of marked lethargy and inappetence followed by hypersalivation, hyperemia o ...201728749266
different origins of two corpora lutea recovered from a pregnant african elephant (loxodonta africana).elephant ovaries contain multiple corpora lutea (cls) throughout pregnancy. two cls (p-1 and p-2) collected from a pregnant african elephant were used to investigate their origin and physiological state in this study. the mrna expressions of prolactin receptor, cyp11a and inhibin betab subunit were higher in p-2 than in p-1, while lhcgr and inhibin betaa subunit mrna were higher in p-1 than in p-2. protein expression of cleaved caspase-3 was detected in p-1 but not in p-2. these results suggest ...201728691383
determinants of seasonal changes in availability of food patches for elephants (loxodonta africana) in a semi-arid african savanna.loss of biodiversity caused by impact of elephants (loxodonta africana) on african woodlands may require a management response, but any action should be based on an understanding of why elephants choose to utilise trees destructively. comprehension of elephant feeding behaviour requires consideration of the relative value of the plant groups they may potentially consume. profitability of available food is partly determined by the time to locate a food patch and, therefore, as a foundation for un ...201728649470
seasonal habitat use by elephants (loxodonta africana) in the mole national park of ghana.to avoid unnecessary waste of limited resources and to help prioritize areas for conservation efforts, this study aimed to provide information on habitat use by elephants between the wet and dry seasons in the mole national park (mnp) of ghana. we compiled coordinates of 516 locations of elephants' encounters, 256 for dry season and 260 for wet season. using nine predictor variables, we modeled the probability of elephant's distribution in mnp. we threshold the models to "suitable" and "nonsuita ...201728616175
sexual dimorphism in african elephant social rumbles.this study used the source and filter theory approach to analyse sex differences in the acoustic features of african elephant (loxodonta africana) low-frequency rumbles produced in social contexts ('social rumbles'). permuted discriminant function analysis revealed that rumbles contain sufficient acoustic information to predict the sex of a vocalizing individual. features primarily related to the vocalizer's size, i.e. fundamental frequency variables and vocal tract resonant frequencies, differe ...201728489908
male african elephants discriminate and prefer vocalizations of unfamiliar females.gaining information about conspecifics via long-distance vocalizations is crucial for social and spatially flexible species such as the african elephant (loxodonta africana). female elephants are known to discriminate individuals and kin based on acoustic cues. specifically, females approached the loudspeaker exclusively with playbacks of familiar individuals with high association indexes, intentionally fusing with their affiliates. for males, which are less bonded, gathering social information ...201728422091
beehive fences as a multidimensional conflict-mitigation tool for farmers coexisting with elephants.increasing habitat fragmentation and human population growth in africa has resulted in an escalation in human-elephant conflict between small-scale farmers and free-ranging african elephants (loxodonta africana). in 2012 kenya wildlife service (kws) implemented the national 10-year conservation and management strategy for the elephant in kenya, which includes an action aimed at testing whether beehive fences can be used to mitigate human-elephant conflict. from 2012 to 2015, we field-tested the ...201728221699
the impact of competition on elephant musth strategies: a game-theoretic model.mature male african savannah elephants are known to periodically enter a temporary state of heightened aggression called "musth", often linked with increased androgens, particularly testosterone. sexually mature males are capable of entering musth at any time of year, and will often travel long distances to find estrous females. when two musth bulls or two non-musth bulls encounter one another, the agonistic interaction is usually won by the larger male. however, when a smaller musth bull encoun ...201728111319
elephants in the understory: opposing direct and indirect effects of consumption and ecosystem engineering by megaherbivores.positive indirect effects of consumers on their resources can stabilize food webs by preventing overexploitation, but the coupling of trophic and non-trophic interactions remains poorly integrated into our understanding of community dynamics. elephants engineer african savanna ecosystems by toppling trees and breaking branches, and although their negative effects on trees are well documented, their effects on small-statured plants remain poorly understood. using data on 117 understory plant taxa ...201627870025
systematic review on the conservation genetics of african savannah elephants.in this paper we review the conservation genetics of african savannah elephants, aiming to understand the spatio-temporal research trends and their underlying factors. as such, we explore three questions associated to the conservation genetics and molecular ecology of these elephants: (1) what are the research trends concerning the conservation genetics ofloxodonta africana? (2) do richer countries conduct more research on the genetics of african elephants? (3) which attributes influence where s ...201627781165
coping with heat: behavioural and physiological responses of savanna elephants in their natural habitat.most of southern africa's elephants inhabit environments where environmental temperatures exceed body temperature, but we do not know how elephants respond to such environments. we evaluated the relationships between apparent thermoregulatory behaviour and environmental, skin and core temperatures for tame savanna elephants (loxodonta africana) that were free-ranging in the hot parts of the day, in their natural environment. environmental temperature dictated elephant behaviour within a day, wit ...201627757237
testing the accuracy of aerial surveys for large mammals: an experiment with african savanna elephants (loxodonta africana).accurate counts of animals are critical for prioritizing conservation efforts. past research, however, suggests that observers on aerial surveys may fail to detect all individuals of the target species present in the survey area. such errors could bias population estimates low and confound trend estimation. we used two approaches to assess the accuracy of aerial surveys for african savanna elephants (loxodonta africana) in northern botswana. first, we used double-observer sampling, in which two ...201627755570
habitat heterogeneity variably influences habitat selection by wild herbivores in a semi-arid tropical savanna ecosystem.an understanding of the habitat selection patterns by wild herbivores is critical for adaptive management, particularly towards ecosystem management and wildlife conservation in semi arid savanna ecosystems. we tested the following predictions: (i) surface water availability, habitat quality and human presence have a strong influence on the spatial distribution of wild herbivores in the dry season, (ii) habitat suitability for large herbivores would be higher compared to medium-sized herbivores ...201727680673
genetic connectivity across marginal habitats: the elephants of the namib desert.locally isolated populations in marginal habitats may be genetically distinctive and of heightened conservation concern. elephants inhabiting the namib desert have been reported to show distinctive behavioral and phenotypic adaptations in that severely arid environment. the genetic distinctiveness of namibian desert elephants relative to other african savanna elephant (loxodonta africana) populations has not been established. to investigate the genetic structure of elephants in namibia, we deter ...201627648236
continent-wide survey reveals massive decline in african savannah elephants.african elephants (loxodonta africana) are imperiled by poaching and habitat loss. despite global attention to the plight of elephants, their population sizes and trends are uncertain or unknown over much of africa. to conserve this iconic species, conservationists need timely, accurate data on elephant populations. here, we report the results of the great elephant census (gec), the first continent-wide, standardized survey of african savannah elephants. we also provide the first quantitative mo ...201627635327
immunolocalization of inhibin/activin subunits and steroidogenic enzymes in the testes of an adult african elephant (loxodonta africana).in this case report, the authors investigated immunolocalization of inhibin α and inhibin/activin βa and βb subunits, as well as steroidogenic enzymes, in the testes of an african elephant. testes were collected from a reproductively active male african elephant (24 yr old) at autopsy. histologically, all types of spermatogenic cells including mature-phase spermatozoa were found in the seminiferous tubules. positive immunostaining for inhibin α and inhibin/activin βa and βb subunits was observed ...201627468011
conserving wildlife amongst the cotton fields. a third of a century of experience at the nazinga game ranch, burkina faso.established in the early 1970 as a participatory wildlife production area, the nazinga game ranch turned into an island of conservation surrounded by cultivation. we asked ourselves how long-term ungulate trends are affected in a context of continuous human pressure. to find out, we compiled and analysed the data of yearly line-transect counts of mammals carried out since 1985. results showed that large species such as the elephant (loxodonta africana) and large antelopes increased or showed sta ...201627350287
zoo visitor perceptions, attitudes, and conservation intent after viewing african elephants at the san diego zoo safari park.elephants in the wild face several conservation issues. with the rebranding of zoos as conservation and education pioneers, they have the ability to both educate and inspire guests to action. the purpose of this research was to analyze visitor perceptions and attitudes toward elephant conservation and outcomes post-exhibit visit. a one-page survey was randomly administered to assess perceptions of elephant behavior, attitudes about elephant conservation, and intended conservation-related outcome ...201627291643
information content and acoustic structure of male african elephant social rumbles.until recently, the prevailing theory about male african elephants (loxodonta africana) was that, once adult and sexually mature, males are solitary and targeted only at finding estrous females. while this is true during the state of 'musth' (a condition characterized by aggressive behavior and elevated androgen levels), 'non-musth' males exhibit a social system seemingly based on companionship, dominance and established hierarchies. research on elephant vocal communication has so far focused on ...201627273586
a comparison of walking rates between wild and zoo african elephants.with increased scrutiny surrounding the welfare of elephants in zoological institutions, it is important to have empirical evidence on their current welfare status. if elephants are not receiving adequate exercise, it could lead to obesity, which can lead to many issues including acyclicity and potentially heart disease. the goal of the current study was to compare the walking rates of elephants in the wild versus elephants in zoos to determine if elephants are walking similar distances relative ...201726963741
standing sedation with medetomidine and butorphanol in captive african elephants (loxodonta africana).doses for standing sedation allowing for various procedures in otherwise inaccessible, untrained captive african elephant bulls are presented. thirty-three standing sedations were performed in 12 males aged 8-30 years (one to four sedations per animal). each bull received a combination of 0.009 ± 0.002 mg/kg medetomidine and 0.03 ± 0.007 mg/kg butorphanol. full sedation was reached on average 25.5 min after injection. the addition of hyaluronidase (1000-2000 iu) significantly reduced time to ful ...201626831175
the consequences of poaching and anthropogenic change for forest elephants.poaching has devastated forest elephant populations (loxodonta cyclotis), and their habitat is dramatically changing. the long-term effects of poaching and other anthropogenic threats have been well studied in savannah elephants (loxodonta africana), but the impacts of these changes for central africa's forest elephants have not been discussed. we examined potential repercussions of these threats and the related consequences for forest elephants in central africa by summarizing the lessons learn ...201626801000
vertical transmission of social roles drives resilience to poaching in elephant networks.network resilience to perturbation is fundamental to functionality in systems ranging from synthetic communication networks to evolved social organization [1]. while theoretical work offers insight into causes of network robustness, examination of natural networks can identify evolved mechanisms of resilience and how they are related to the selective pressures driving structure. female african elephants (loxodonta africana) exhibit complex social networks with node heterogeneity in which older i ...201626711491
using poaching levels and elephant distribution to assess the conservation efficacy of private, communal and government land in northern kenya.efforts to curb elephant poaching have focused on reducing demand, confiscating ivory and boosting security patrols in elephant range. where land is under multiple uses and ownership, determining the local poaching dynamics is important for identifying successful conservation models. using 2,403 verified elephant, loxodonta africana, mortality records collected from 2002 to 2012 and the results of aerial total counts of elephants conducted in 2002, 2008 and 2012 for the laikipia-samburu ecosyste ...201526407001
elephant resource-use traditions.african elephants (loxodonta africana) use unusual and restricted habitats such as swampy clearings, montane outcrops and dry rivers for a variety of social and ecological reasons. within these habitats, elephants focus on very specific areas for resource exploitation, resulting in deep caves, large forest clearings and sand pits as well as long-established and highly demarcated routes for moving between resources. we review evidence for specific habitat exploitation in elephants and suggest tha ...201626359083
intensity of play behavior as a potential measure of welfare: a novel method for quantifying the integrated intensity of behavior in african elephants.to the authors' knowledge there is currently no discrete index to measure the integrated intensity of a play bout in mammals, despite the potential for using intensity and duration of play bouts as a measure of physical activity and welfare. this study was developed to test an equation that quantified the intensity and duration of play bouts in a particularly gregarious mammal, african elephants (loxodonta africana) housed at the san diego zoo safari park in escondido, ca. to quantify these beha ...201526251201
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