Search Results (74)

Background: Sexual dimorphism in Asian elephants (Elephas maximus) is evident in external features, but skeletal differences remain underexplored. This study aimed to examine the skull, scapula, and pelvis using traditional morphometric methods to assess sex-related variation. Methods: Eleven skeletal specimens were analyzed, including nine skulls, eleven pelves, and eighteen scapulae. Linear measurements were obtained using measuring tape and calipers. Statistical analyses included Mann–Whitney U tests, Pearson’s correlation, and logistic regression for sex prediction. Results: No significant differences were found in skull measurements between sexes. However, the pelvis and scapula exhibited notable variation. Significant pelvic parameters included pelvic girdle length (p = 0.024), symphysis length (p = 0.012), and pubis shaft perimeter (p = 0.048). Scapular differences were observed in diagonal breadth, mediolateral width, and spine length. Logistic regression using pelvic measurements yielded 100% accuracy for female classification and 66.67% for males, with an overall prediction accuracy of 90.91%. Conclusions: The pelvis demonstrated the highest reliability for sex determination. These findings enhance the anatomical understanding of Asian elephants and support applications in conservation, forensic science, and population studies. Future research with larger sample sizes and advanced imaging may improve the precision of morphometric sex prediction models. Full article

Herpes simplex virus type 1 (HSV-1) is a globally prevalent pathogen that can infect a variety of animal species as well as humans. However, existing antiviral therapies are constrained in their capacity to effectively target viral latency and prevent recurrent infections. Antimicrobial peptides (AMPs), particularly cathelicidins, as part of innate immune system have demonstrated broad-spectrum efficacy against viral pathogens. In this study, four peptides derived from Elephas maximus cathelicidin EM were designed and optimized (EM-1 to EM-4). We identified low toxicity peptide derivatives through hemolytic and cytotoxicity assays, quantified their anti-HSV-1 activity by determining IC₅₀. Antiviral mechanisms were investigated using RT-qPCR and antiviral efficacy was ultimately validated in C57BL/6J mice through viral load quantification in brain, lung, and heart tissues. Our findings revealed that EM-1 significantly inhibited HSV-1 replication in U251 cells. In a murine footpad inoculation model, EM-1 administration substantially reduced viral loads and alleviated inflammatory responses. Histological assessment demonstrated that EM-1 treatment mitigated HSV-1 induced tissue damage in infected mice. We also found that EM-1 exerted its antiviral effects by upregulating the expression of interferon-gamma and its downstream genes, such as ISG15 and MX1. These findings indicated that EM-1 is a dual function peptide that inhibits replication of HSV-1 as well as enhances host antiviral immunity. Collectively, this study highlights the therapeutic potential of elephant cathelicidin derived peptides in antiviral development. Full article

This case report details the successful rehabilitation of a 31-year-old male Asian elephant (Elephas maximus) presenting with an abnormal left forelimb gait following chronic traumatic injury. The elephant exhibited a distinctive circumduction gait with a semicircular arc movement, characterized by limited flexion at the elbow and carpus, along with compensatory proximal shrugging during the swing phase. Diagnostic evaluations revealed joint space narrowing and ligament fibrosis, while biomechanical gait analysis using inertial measurement units highlighted significant asymmetries between affected and unaffected limbs. An interprofessional team developed a comprehensive rehabilitation protocol that integrated peripheral magnetic stimulation, task-specific therapeutic walking with adjustable obstacles, and progressive strengthening exercises. At the eight-week follow-up, improvements were observed in cross-correlation coefficients of limb movement and imaging assessments, indicating enhanced symmetry and structural improvements with reduced fibrosis. However, persistent discrepancies in elbow functions suggest that further targeted rehabilitation may be warranted. This report underscores the potential of a coordinated interprofessional approach to restore functional gait patterns in elephants and offers valuable insights for future rehabilitative strategies in managing complex musculoskeletal injuries in large mammals. Full article

Xishuangbanna, located in southern Yunnan, China, is a vital tropical rainforest reserve supporting rich biodiversity, including the endangered Asian elephant (Elephas maximus). Increasing human activities, such as urbanization and agricultural expansion, have degraded habitats and intensified human–elephant conflicts, adding to the challenges of conservation. This study integrates habitat quality assessment and conflict risk analysis using the InVEST model across 2128 villages, considering land use and habitat threats like cropland and roads. The model reveals significant overlap between high-conflict zones and low-quality habitats near key reserves, underscoring the need for targeted conservation strategies. We propose establishing Ecological Source Areas (ESAs) to protect high-quality habitats and Ecological Restoration Zones (ERZs) to improve ecological conditions in low-quality, high-conflict zones. ESAs are essential for providing continuous ecosystem services and ensuring ecological security, while ERZs focus resources on areas with high conflict risk that urgently need restoration. Additionally, we recommend creating ecological corridors to connect fragmented habitats, enhance connectivity, support herd interactions, and reduce conflicts by expanding elephants’ safe roaming range. This integrated framework emphasizes habitat protection, ecological restoration, and conflict mitigation while accounting for human dynamics to support sustainable conservation. Reducing overlap between human and elephant activities remains a key objective. Future research should refine these models with more detailed data and extend their application to other regions, focusing on adaptive management and monitoring to address evolving ecological and human dynamics. Full article

Obesity is a prevalent health issue among captive wildlife, but the obesity status of captive Asian elephants (Elephas maximus) in China has not been systematically investigated. This study assessed obesity in 204 captive Asian elephants across 43 facilities by recording seven potentially relevant variables: sex, age, daily feed supply, proportion of high-calorie feed, outdoor enclosure area, outdoor time, and foot disorders. Body condition was evaluated using visual scoring, revealing a high prevalence of overweight and obesity, particularly in zoo-kept elephants. Over 70% of captive Asian elephants in China were classified as overweight or obese. Statistical analysis indicated that insufficient outdoor time is likely a primary contributor to obesity among zoo elephants. We recommend extending outdoor time and regulating the supply of high-calorie feeds (e.g., fruits, vegetables, and pellets) to promote exercise and balance energy intake. Additionally, implementing positive reinforcement training for routine health checks, including foot exams and blood sampling, could improve data collection on elephant health and welfare, ultimately enhancing obesity management and overall animal well-being. Full article

This study aimed to detect seasonal and species differences in serum 25-hydroxy vitamin D (25(OH)D) concentrations during summer and winter months in captive pachyderms in Europe. Both elephant species had low 25(OH)D while African elephants did not show a seasonal variation. Asian elephants had significantly higher 25(OH)D compared to their African counterparts but also did not show a seasonal difference. Both rhinoceros species investigated had higher 25(OH)D compared to both elephant species; the Indian rhinoceros had high circulating levels year-round, while the black rhinoceroses showed significantly lower 25(OH)D in winter. Malayan tapirs have very low 25(OH)D, comparable to horses. The higher 25(OH)D of elephants and rhinoceroses could indicate that elephants and rhinoceroses are capable of producing vitamin D. This might indicate that the Indian rhinoceroses are capable of producing enough endogenous vitamin D year-round at latitudes around 52° N, while both elephant species and the black rhinoceros are not. This study also showed that it is likely that both elephant species and rhinoceros species are capable of absorbing cholecalciferol from the digestive tract, according to the existing literature, while tapirs may not. Full article

When standard methods of human–elephant conflict mitigation are not successful, free-ranging wild elephants may continue to come into close contact with people. This results in more frequent and severe conflict, with consequences ranging from crop raiding to loss of human and elephant lives. Understandably, in such situations, local communities may want to be rid of entire herds of elephants. Historically, one of the strategies the Myanmar Government practiced to resolve human–elephant conflict was the capture of whole herds using the Kheddah system. This involved trapping the herd in a stockade, immediately followed by on-site post-capture taming. After taming, the captured elephants were utilized as logging elephants. Elephants worked in timber extraction, retired at age 55 years and were then cared for by the Government until they died. The capture of wild elephants by the Kheddah system was formally banned in Myanmar in 1985 but occasional, small-scale, captures were allowed until 2013 under the strict control of the Myanmar Government. These operations were aimed primarily at capturing elephants involved in human–elephant conflict, rather than to supplement the working elephant population. One of the last Kheddah operations, organized and managed by the author, was conducted in 1996 at the Taikkyi township of the Yangon Region, as a last resort to end human–elephant conflict in an emergency. While chemical immobilization was being used at this time, it was not logistically possible with the high numbers of elephants engaged in the conflict. This review aims to record the history of an activity that was an important element of Myanmar’s timber industry more than three decades ago. In this paper, the author presents a description of Kheddah not to endorse it, but to document (1) the Myanmar elephant population management strategy in the past, before it is forgotten, and (2) the practicality of the Kheddha operation when the singly selected commonly- used immobilization or noosing method of elephant capture is unfeasible. The author attempts to shed light on the modern veterinary procedures that may significantly reduce the notorious historical outcome of Kheddha, especially the resulting mortality of captured elephants, should the Kheddha system of capture ever be used as an emergency solution for ongoing problems of human–elephant conflict in the range states of Asia. Full article

Optimal veterinary care of managed elephant populations is vital due to the continued decline of wild populations. Appropriate health monitoring and accurate disease diagnosis include hematologic evaluation. Elephant hematology is distinctive in that elephants have high percentages of monocytes in health. Elephant monocytes also have unusual morphology, a feature shared with manatees and rock hyraxes. Manual white blood cell counting is used for elephant hematology, as analyzers are generally inaccurate. The aims of this study were to evaluate basic cell isolation and functional testing protocols for use in elephant monocyte research, and to test several available antibodies via flow cytometry for use in elephant monocyte identification. Peripheral blood samples from five Asian elephants (Elephas maximus) were used. Methods for monocyte isolation and evaluation of phagocytic function were established. Putative lymphocyte and monocyte populations were identified using a scatter on flow cytometry. Antibodies against CD11b, CD11c, CD14, and ionized calcium-binding adapter molecule 1 (IBA1) were tested, with IBA1 showing the highest apparent diagnostic utility in labeling monocytes. Combined flow cytometric scatter and IBA1 positivity appear to identify Asian elephant monocytes. These data provide a methodologic basis for further investigation into elephant monocyte function and immune response to infection. Full article

The abdominal testes of Asian elephants show normal spermatogenesis. Heat shock in cryptorchid testes elevates heat shock factor (HSF) expression, leading to germ cell apoptosis, while increased heat shock proteins (HSPs) levels provide protection. To investigate how heat shock affects elephant spermatogenic cells, focusing on heat shock-related molecules and the cell death mechanism, immunohistochemistry and TUNEL staining were employed to assess the immunoexpression of several heat shock-related molecules and the status of apoptosis in elephant fibroblasts (EF) induced by heat shock stimulus. Additionally, the immunoexpression of heat shock-related molecules and cell proliferation status in the elephant spermatogenic cells. Our finding indicated that heat shock-induced HSF1 immunoexpression in EF leads to apoptosis mediated by T-cell death-associated gene 51 (TDAG51) while also upregulating HSP70 to protect damaged cells. In elephant spermatogenic cells, immunostaining revealed a predominance of proliferating cell nuclear antigen (PCNA)-positive cells with minimal TDAG51- and TUNEL-positive cells, suggesting active proliferation and apoptosis suppression during normal spermatogenesis in the abdominal testis. Interestingly, spermatogonia co-immunoexpressed HSF1 and HSP90, potentially reducing apoptosis through protective mechanisms different from those observed in other mammals. Spermatogenic cells did not show immunolocalisation of HSP70, and hence, it may not contribute to protecting the spermatogonia from heat shock because the transcriptional activity of HSF1 is suppressed by HSP90A binding. This study provides insight into the specific heat shock response and defence mechanisms in elephant spermatogenic cells and may contribute to our understanding of species-specific adaptation to environmental stresses of the testis. Full article

Three cases of double infection with elephant endotheliotropic herpesvirus (EEHV) types 1A and 4 in captive Asian elephants are presented. The first calf was a 4-year-old female that showed initial signs of lethargy and depression. The second calf was a 6-year-old female that displayed signs of depression and diarrhea and died within 48 h of the start of supportive treatment. The third was a 2-year-old male that died suddenly while living with the herd. Necropsies were performed in the first and second elephants, while only a tongue sample was collected from the third calf. EEHV infection was confirmed via quantitative PCR (qPCR) and gene sequencing, revealing double subtypes of EEHV1A and -4 infections. This study describes the hematological and pathological characteristics within the host following double EEHV infection. Full article

Elephant endotheliotropic herpesviruses (EEHVs), of which eleven (sub)species are currently distinguished, infect either Asian (Elephas maximus) or African elephants (Loxodonta species). While all adult elephants are latently infected with at least one EEHV (sub)species, young elephants, specifically those with low to non-detectable EEHV-specific antibody levels, may develop fatal hemorrhagic disease (EEHV-HD) upon infection. However, animals with high antibody levels against EEHV(1A) gB, an immunodominant antigen recognized by antibodies elicited against multiple (sub)species, may also occasionally succumb to EEHV-HD. To better define which animals are at risk of EEHV-HD, gB and gH/gL ELISAs were developed for each of the Asian elephant EEHV subspecies and assessed using 396 sera from 164 Asian elephants from European zoos. Antibody levels measured against gB of different (sub)species correlated strongly with one another, suggesting high cross-reactivity. Antibody levels against gH/gL of different subspecies were far less correlated and allowed differentiation between these (sub)species. Importantly, while high gB-specific antibody levels were detected in the sera of several EEHV-HD fatalities, all fatalities (n = 23) had low antibody levels against gH/gL of the subspecies causing disease. Overall, our data indicate that (sub)species-specific gH/gL ELISAs can be used to identify animals at risk of EEHV-HD when infected with a particular EEHV (sub)species. Full article

Endangered Asian elephants (Elephas maximus) find themselves at the center of debates involving politics, land use, human–wildlife conflict, and environmental justice. The intensity of such debates has led scholars to label conservation challenges as wicked problems with profound implications on local and global practice. In elephant range states such as Nepal, these debates are made more complex through human ‘ownership’ of endangered individuals for use in tourism, worship, or co-work. Human perspectives on the ethics of using animals for tourism are changing, even in areas heavily reliant on the tourism industry for survival. These debates become inflamed when non-residents take on adversarial positions despite an acceptance of the ‘ownership’ or ‘use’ of endangered individuals among local communities. Novel approaches are needed if there is any hope of establishing a common ground upon which to build relationships which may benefit community members, international interests, and endangered individuals. Full article

Saltlicks are fundamental resources for wild Asian elephants (Elephas maximus). This study aimed to assess the nutrients found in natural saltlicks (NSs) and artificial saltlicks (ASs), as well as general soils (GS) in the natural forest of Salakphra Wildlife Sanctuary (SWS) and a restoration area of Kui Buri National Park (KNP), a which is a forest in Western Thailand. We monitored 33 NSs, 35 ASs, and 20 GSs used by wild Asian elephants. In both areas, the K, Mg, Fe, and Cu in NSs were significantly higher than in ASs. The Ca and Zn in NSs of KNP were lower than the ASs of SWS. The salinity of ASs was the highest, making it significantly higher than that of the NSs in both areas. The ASs can supplement Na, thereby increasing salinity in both areas. The Ca, K, Mg, Fe, and Cu in NSs were significantly higher than in ASs, making them a primary target for elephants. These findings have consequences for conserving elephants and other large herbivores by supplementing essential macro- and micro-nutrients in ASs. Full article

Crop-raiding by elephants is one of the most prevalent forms of human–elephant conflict and is increasing with the spread of agriculture into wildlife range areas. As the magnitude of conflicts between people and elephants increases across Africa and Asia, mitigating and reducing the impacts of elephant crop-raiding has become a major focus of conservation intervention. In this study, we tested the responses of semi-captive elephants to the “smelly” elephant repellent, a novel olfactory crop-raiding mitigation method. At two trial sites, in Zambia and Thailand, African elephants (Loxodonta africana) and Asian elephants (Elephas maximus) were exposed to the repellent, in order to test whether or not they entered an area protected by the repellent and whether they ate the food provided. The repellent elicited clear reactions from both study groups of elephants compared to control conditions. Generalised linear models revealed that the elephants were more alert, sniffed more, and vocalised more when they encountered the repellent. Although the repellent triggered a response, it did not prevent elephants from entering plots protected by the repellent or from eating crops, unlike in trials conducted with wild elephants. Personality played a role in responses towards the repellent, as the elephants that entered the experimental plots were bolder and more curious individuals. We conclude that, although captive environments provide controlled settings for experimental testing, the ecological validity of testing human–elephant conflict mitigation methods with captive wildlife should be strongly considered. This study also shows that understanding animal behaviour is essential for improving human–elephant coexistence and for designing deterrence mechanisms. Appreciating personality traits in elephants, especially amongst “problem” elephants who have a greater propensity to crop raid, could lead to the design of new mitigation methods designed to target these individuals. Full article

Aversive geofencing devices (AGDs) or animal-borne satellite-linked shock collars might become a useful tool to mitigate human-elephant conflict (HEC). AGDs have the potential to condition problem elephants to avoid human-dominated landscapes by associating mild electric shocks with preceding audio warnings given as they approach virtual boundaries. We assessed the opinions of different stakeholders (experts, farmers, and others who have and have not experienced HEC; n = 611) on the potential use of AGDs on Asian elephants. Most respondents expressed positive opinions on the potential effectiveness of AGDs in managing elephant movement (62.2%). About 62.8% respondents also provided positive responses for the acceptability of AGDs if pilot studies with captive elephants have been successful in managing their movements. Some respondents perceived AGDs to be unacceptable because they are unethical or harmful and would be unsuccessful given wild elephants may respond differently to AGDs than captive elephants. Respondents identified acceptability, support and awareness of stakeholders, safety and wellbeing of elephants, logistical difficulties, durability and reliable functionality of AGDs, and uncertainties in elephants’ responses to AGDs as potential challenges for implementing AGDs. These issues need attention when developing AGDs to increase support from stakeholders and to effectively reduce HEC incidents in the future. Full article