Search Results (126)

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

Cobboldia elephantis (Oestridae: Gasterophilinae) is an obligate parasite of the alimentary tract of the Asian elephant, causing gastric myiasis. Current knowledge of its first instar larval morphology has been limited to observations under light microscopy, significantly constraining our understanding of morphological evolution within the genus Cobboldia and the broader subfamily Gasterophilinae. In this study, we provided ultrastructural and three-dimensional characterizations of C. elephantis using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) based on newly hatched first instar larvae. Features of the first instar larva of C. elephantis, which are either unique or shared with C. loxodontis Brauer, 1896, include (i) three pairs of mouthhooks, (ii) posterior spiracles bearing peristigmatic tufts, (iii) anal division with two spine-clusters and a row of elongated spines, and (iv) a planed, button-like sensilla and a sensillum placodeum. We also compared the first instar larval morphology of C. elephantis with that of Cobboldia loxodontis, Gyrostigma rhinocerontis (Owen, 1830), Gasterophilus pecorum (Fabricius, 1794), Portschinskia magnifica Pleske, 1926, and Oestrus ovis Linnaeus, 1758. Species of Gasterophilinae share several unique features of the first instar larva, including (i) an anal division composed of three subdivisions, (ii) spiracular slits on the posterior spiracles, and (iii) conserved positioning of thoracic sensilla. These findings fill a key gap in our knowledge of C. elephantis larval morphology and suggest that these distinctive structures play a role in adaptation to its parasitic lifestyle. 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

The endangered Asian elephant, Thailand’s national symbol, is increasingly affected by human–elephant conflict (HEC), now a critical conservation and socio-economic concern. This study examined 341 HEC occurrences in 34 out of 77 Thai provinces between 2014 and 2023, based on data from official and private sources. These events resulted in both human and elephant casualties and property damage. Occurrences peaked in 2018 and 2023, with significant associations found between conflict rates, regions, and periods. The Eastern region and the July-to-October period (the rainy season) emerged as key high-risk areas, likely related to additional factors such as high elephant densities and abundant crop production. Most HECs occurred in agricultural land, where elephants searched for food. The findings suggest that the July-to-October period requires heightened surveillance and additional preventive actions. The Eastern region remains a priority for intervention due to its ongoing vulnerability and the movement of elephants across provincial boundaries. Furthermore, the rise of the Northeastern region as a new hotspot underlines the need for proactive measures to prevent escalation. Full article

Background: The interaction and co-evolution between the gut microbiome and the host play important roles in the host’s physiology, nutrition, and health. Diet is considered an important driver of differences in the gut microbiota; however, research on the relationship between the gut microbiota and diet in Asian elephants remains limited. Methods: In this study, we explored the gut microbiota structure and its relationship with diet in different populations of Asian elephants through metagenomic sequencing, combined with previously published dietary data. Results: This study found that the dominant gut microbiota of Asian elephants includes the phyla Bacillota (29.85% in BP, 22.79% in RC, 21.89% in SM, 31.67% in ML, and 33.00% in NGH), Bacteroidota (25.25% in BP, 31.44% in RC, 16.44% in SM, 25.73% in ML, and 23.74% in NGH), and Spirochaetota (3.49% in BP, 6.18% in RC, 1.71% in SM, 2.69% in ML, and 3.52% in NGH), with significant differences in the gut microbiota among different populations. Correlation analysis between the gut microbiota and diet revealed that dietary diversity did not directly affect the alpha diversity of the gut microbiota. However, specific food types might play a key role in shaping the gut microbiota structure by regulating the abundance of certain microbiota. Conclusions: This study reveals significant differences in the gut microbiota structure among different populations of Asian elephants and explores the impact of diet on the structure. The results provide foundational data for a deeper understanding of the gut microbiota structure of Asian elephants and offer important references for the scientific conservation and precise management strategies of this species. Full article

In countries and regions where Asian elephants are distributed, human–elephant conflict has become an important ecological and socio-economic issue. As one of the major habitats of Asian elephants, China faces severe challenges. Based on the theory of planned behavior and the risk perception theory, this study takes the survey data of 449 smallholder farmers in the Asian elephant distribution areas of Pu’er City, Yunnan Province as samples and uses the Tobit model and the mediating effect model to empirically analyze the impact of human–elephant conflict on farmers’ land use efficiency and its mechanism. The results show the following: (1) The human–elephant conflict risk perception has a significant negative impact on farmers’ land use efficiency. A one-unit increase in risk perception decreases land use efficiency by 250.34 CNY/mu. (2) Social networks positively moderate the negative impact of the human–elephant conflict risk perception on farmers’ land use efficiency, further strengthening the negative impact of risk perception. (3) From the perspective of the mechanism, the human–elephant conflict risk perception increases the likelihood of farmers changing their land use behavior. Farmers with high risk perception tend to reduce agricultural capital investment, which in turn leads to a decline in land use efficiency. In view of this, this paper puts forward suggestions in terms of strengthening ecological monitoring and control, increasing support for agricultural production, and guiding rational social network communication, providing theoretical support and practical guidance for alleviating human–elephant conflict and improving farmers’ land resource use efficiency. Full article

The early detection of lameness in elephants is essential for effective treatment and welfare enhancement, but subtle gait abnormalities are often difficult to identify visually. This study aimed to evaluate vertical movement symmetry in Asian elephants using cross-correlation analysis of data from inertial measurement units (IMUs). Six elephants were assessed, including individuals with normal gait and one exhibiting an abnormal gait. IMU sensors were attached to the proximal and distal segments of the forelimbs and hindlimbs to record vertical movements during straight-line walking. Cross-correlation coefficients were calculated to quantify the symmetry between the left and right limbs, providing an objective measure of gait patterns. This method provided an objective assessment of gait patterns and demonstrated potential in detecting lameness in elephants. This approach could facilitate the early identification of gait abnormalities, enabling timely interventions and potentially improving treatment outcomes and the welfare of captive elephant populations. Further studies involving a larger number of elephants with confirmed gait abnormalities are necessary to validate the robustness and reliability of this approach. Full article

The increasing threat of biological invasion poses significant challenges to global ecosystems, necessitating urgent management measures. This study investigated the potential of biochar derived from invasive plant Chromolaena odorata, produced through anaerobic digestion, as a tool for mitigating the soil legacy effects of this species and restoring the plant community. Soil samples were collected from artificially constructed plots of invasive plant communities and were subjected to treatments with different levels of fungicide and biochar addition. Potted plant communities replicating the original species composition were established, and biomass were used to evaluate the effectiveness of soil restoration. Our results demonstrated that soil sterilization enhanced plant biomass, with invasive plants showing a more pronounced increase compared to native species, indicating different responses to the soil biota. The addition of biochar influenced plant biomass, with an optimal biochar concentration of 2% of the soil mass, promoting the growth of native plants. The application of biochar in conjunction with soil sterilization facilitated the restoration of native communities in areas with low invasion intensity. Overall, these findings provide valuable insights into the potential of biochar-based strategies for managing invasive plants and restoring ecosystems, underscoring the necessity for further research to optimize field applications and evaluate ecological impacts. Full article

Rural landscapes are experiencing ecosystem degradation due to urbanization and rapid suburban expansion. Ecosystem services derived from natural resources and essential public services facilitated by social capital collectively address the growingly diverse social and ecological requirements of rural residents. Even so, ecosystem services and public services are often trade-offs, highlighting the necessity to enhance their coordinated development. However, it remains unclear how to use the identified thresholds to delineate functional zones. This will scientifically guide sound and efficient spatial planning and ecological management. This study takes the suburban countryside of Jiangning in Nanjing as the study area. It explores the inclusion of the threshold value of rural public services and ecosystem services in the strategic design of sustainable suburban development in China. First, we quantify and map six types of ecosystem services (ESs) and 13 types of rural public services (RPSs). Secondly, we use the piecewise linear regression method to identify the response and threshold of 13 types of RPSs to six kinds of ESs. Finally, the combination and classification of threshold values are used to divide functional areas, and space-specific management and planning suggestions are put forward. The results are as follows (1) With the increase in RPSs, all ESs respond with a downward trend. (2) In addition to the negative linear relationship between education and social welfare services and ESs, the response thresholds of other RPSs and ESs were identified. (3) According to multiple density threshold analysis of each RPS’s response to ESs, four functional areas were obtained. We emphasize the priority of spatial planning and management, that is, the priority management of “ESs enhancement area and RPSs optimization area”. (4) The threshold values of ESs and RPSs can be used as tools to delineate functional zones and guide the spatial planning and management of rural functional areas. In general, our research helps ensure the maximization of rural ecological benefits while also meeting the growing diversity of needs of rural residents and enabling efficient, phased, gradient, and precise spatial management of suburban rural ecosystems and public services to promote the sustainable development of suburban rural areas and realize rural revitalization. Full article

Background/Objectives: Elephant endotheliotropic herpesvirus (EEHV) causes lethal hemorrhagic disease (HD) in Asian and African elephants in human care and the wild. It is the leading cause of death for young Asian elephants in North American and European zoos despite sensitive diagnostic tests and improved treatments. Thus, there is a critical need to develop an effective vaccine to prevent severe illness and reduce mortality from EEHV-HD. We generated a multi-antigenic EEHV mRNA vaccine to address this need that encodes the EEHV1A-subtype glycoproteins gB, gH, gL, and gO. These conserved proteins are the entry machinery for several herpesviruses in the betaherpesvirus subfamily and elicit humoral and cellular immunity in naturally infected elephants. Methods: Outbred CD-1 mice were vaccinated with two doses of an mRNA vaccine comprising modified EEHV1A gB, gH, gL, and gO mRNAs encapsulated into lipid nanoparticles. Humoral and T-cell immunity was assessed three weeks after the first dose or three weeks after the booster dose using luciferase immunoprecipitation system assays and flow cytometry, respectively. Results: The CD-1 mice vaccinated once had detectable antibody titers against gB, gH, and gL that increased significantly three weeks after a booster dose. Activated CD4⁺ and CD8⁺ T cells secreting cytokines associated with a T_H1 response were induced against all four glycoproteins. No adverse effects were observed following one or two doses of the vaccine. Conclusions: We found that gB, gH, gL, and gO as a multivalent vaccine stimulated robust humoral and cell-mediated immunity. This is a critical step for moving this candidate EEHV1A mRNA vaccine into clinical trials in Asian elephants. 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

Since the human population is growing beyond the earth’s ability to sustain it, more people are being brought into contact with wildlife, leading to increasing human–wildlife conflict. The Asian elephant, a wide-ranging megaherbivore, is being increasingly threatened by human–elephant conflict [HEC]. Its conservation depends on identifying the causes of HEC and implement measure to mitigate the HEC effectively. We studied the drivers of HEC among five forest divisions in Western Ghats, India, that support a high density of elephants across Asia. Comparing the last six years’ data on HEC with 26 ecological covariates in the GLMM framework, we identified spatiotemporal variations and drivers of crop, and property damages and human casualties. Spatially, HEC was highest in the territorial division and lowest in those declared as Protected Areas earlier. The comparison of crop damage with covariates showed that crop damage decreased with the grass biomass index, elephant density, extent of dry-thorn, and deciduous habitats, and forest range area, while it increased with adult male % and forest range perimeter. Similarly, the property damage by elephants increased with crop damage frequency and human settlement/cultivation area, but decreased with grass biomass, forest range area, and deciduous habitat area. Human casualties due to elephants increased with property damage, ambient temperature, and forest range perimeter, but decreased with grass biomass. Overall, the decrease in HEC with grass biomass, and the increase in HEC with human settlement and forest range perimeter indicate that anthropogenic pressure that decreases the grass biomass and degrades the habitat is the likely root cause of HEC, and minimizing it would reduce overall HEC. Full article

Human activities have both positive and negative impacts on forests, altering the extent and composition of various forest vegetation types, and increasing uncertainty in ecological management. A detailed understanding of the historical distribution of forest vegetation is crucial for local conservation efforts. In this study, we integrated phenological features with climatic and terrain variables to enhance the mapping accuracy of forest vegetation in Yunnan. We mapped the historical distributions of five forest vegetation type groups and nine specific forest vegetation types for 2001, 2010, and 2020. Our findings revealed that: (1) rubber plantations can be effectively distinguished from other forest vegetation using phenological features, coniferous forests and broad-leaved forests can be differentiated using visible spectral bands, and environmental variables (temperature, precipitation, and elevation) are effective in differentiating forest vegetation types under varying climate conditions; (2) the overall accuracy and kappa coefficient increased by 14.845% and 20.432%, respectively, when climatic variables were combined with phenological features, and by 13.613% and 18.902%, respectively, when elevation was combined with phenological features, compared to using phenological features alone; (3) forest cover in Yunnan increased by 2.069 × 10⁴ km² (10.369%) between 2001 and 2020. This study highlights the critical role of environmental variables in improving the mapping accuracy of forest vegetation in mountainous regions. 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