Search Results (390)

When analyzing the long-term viability of small, declining populations, it is essential to recognize that inbreeding and the erosion of genetic diversity are primarily driven by the effective population size, which is often a fraction of the total census count. The globally endangered Lear’s macaw (Anodorhynchus leari) is a restricted-range species endemic to the Caatinga ecoregion in NE Brazil. This species was only known in captivity due to wildlife illegal trade, until 1978, when a small population close to extinction was discovered in the wild, estimated at ca. 60 individuals in 1983. Conservation efforts have allowed for population recovery in recent decades, reaching a population of ca. 2273 individuals in 2022. Given these drastic population changes, a genetic assessment is important to empower conservation strategies with knowledge about the level of genetic variability, population genetic structure, inbreeding levels, and demographic history. We used a set of eight species-specific microsatellites to provide the first genetic assessment of the wild population of this species by genotyping non-invasive samples (molted feathers) collected in the known breeding and roosting sites of the species. Our results revealed a low effective population size (N_e = 49–80), which represents the main conservation concern. We also observed evidence of past bottlenecks. However, moderate levels of genetic diversity, no evidence of inbreeding, and a wide connectivity across the study area confirm a single population and set the ground for the potential natural recovery of this species and the recolonization of breeding sites across its former range. Full article

Understanding antimicrobial resistance (AMR) within a One Health framework requires examining how human–animal–environment interactions shape bacterial populations, and captive wildlife offers a unique context to explore these dynamics. This study aimed to characterise the phenotypic resistance and virulence profiles of Escherichia coli isolated from faecal samples of captive non-domestic felids housed in a wildlife sanctuary in the United Kingdom and evaluate the influence of captive conditions in E. coli traits. A total of 41 faecal samples were collected from 36 animals representing 11 non-domestic felid species, from which it was possible to obtain 108 E. coli isolates identified using IMViC testing. The isolates were characterised regarding their susceptibility to 12 antibiotics by disc diffusion and screened for the phenotypic expression of six virulence factors, including protease, DNase, gelatinase, lecithinase, haemolysins, and biofilm formation. The highest resistance rates were observed for tetracycline (19.4%) and ampicillin (10.2%), while isolates presented complete susceptibility regarding half of the tested antibiotics. Also, 9.3% of the isolates presented a multidrug-resistant profile. Biofilm formation was the only virulence factor expressed by the isolates under study (8.3%). Significant associations were detected between resistance outcomes and levels of human proximity and enclosure type. These findings suggest that captivity-related factors may influence AMR profiles in wild felids and highlight the importance of continued AMR surveillance and appropriate management practices to reduce selective pressures in captive wildlife. Full article

In Pteropus spp., metabolic bone disease has been consistently associated with fruit-based diets that are deficient in calcium, vitamin D precursors, and protein, as well as limited ultraviolet B (UVB) exposure, as reported in zoological surveys and clinical observations. Comparative mammalian physiology suggests that dysregulation of the endocrine axis involving parathyroid hormone (PTH), fibroblast growth factor 23 (FGF23), calcitonin, and calcitriol may contribute to disease development, although direct species-specific endocrine data in flying foxes remain scarce. This narrative review synthesizes current knowledge from published zoological reports, clinical observations, and comparative mammalian physiology regarding the etiology, pathophysiology, and clinical expression of metabolic bone disease in captive flying foxes. Much of the available evidence is derived from juvenile Pteropus vampyrus, and its applicability to other Pteropus species remains to be fully established. The limited availability and consistency of existing data, together with the scarcity of controlled experimental and longitudinal studies, necessarily constrain the conclusions that can be drawn. Nevertheless, this review highlights key nutritional and environmental risk factors and summarizes evidence-informed preventive management strategies to improve skeletal health and welfare in managed Pteropus populations. Full article

Under the Eighth Amendment, prisons are legally mandated to provide constitutionally adequate standards of medical care to the incarcerated. But how do we make sense of a carceral structure in which the very delivery of medical care results in preventable death? This article offers a carceral case study of how prison medical care during the era of mass incarceration generates racialized mortality at the Louisiana State Penitentiary, also known as Angola Prison. By analyzing caselaw documents drawn from the docket of Lewis v. Cain, an ongoing lawsuit alleging inadequate medical care at Angola, this article seeks to address the limits of pursuing relief from prison conditions through legal interventions and reforms that are always yet to arrive. Rather than examining prison medical care and preventable death as problems to be reformed, this project aims to develop theoretical insight into how Angola Prison enacts “medical violence” against its captive population. This refers to the use of prison healthcare capacities to harm rather than affirm the lives of the incarcerated. As this case study argues, medical violence operates through organized abandonment, disregard, and carceral extraction, which together extend the life of the prison through the deaths of its captive population. Full article

Over the last century, anthropogenic activities have contributed to habitat degradation and fragmentation but have also affected the individual health of animals. In this study, we investigated the effect of environmental differences on the gut microbiome of Herring Gulls (Larus argentatus) by collecting fresh faecal samples from ten geographically different populations in the UK, including captive and wild birds, and comparing the resulting gut microbiome diversity and composition. A significantly higher alpha diversity was identified in captive gulls than in urban and suburban gulls for the 46 sequenced samples. When comparing gut microbiome composition, urban inhabitants exhibited a higher abundance of Ligilactobacillus and a lower abundance of Streptococcus than suburban gulls. Such differences could suggest a highly polluted environment for urban-dwelling gulls, while suburban populations could have a wider foraging range and a more diverse diet. In addition, samples from Bristol, West Kirby, Gloucester and Liverpool were all characterised by a significantly higher abundance of one or more of the other bacterial taxa. The high proportion of Mycoplasma could indicate avian mycoplasmosis in the Liverpool population. This study sheds light on the understudied subject of the wild avian gut microbiome and its possible application to wildlife health and disease management. Full article

The Guizhou snub-nosed monkey (Rhinopithecus brelichi), a critically endangered primate endemic to China’s Fanjingshan National Nature Reserve, faces severe population decline, with fewer than 850 individuals remaining in the wild. As a high-altitude species adapted to long, snowy winters, its survival depends on behavioral thermoregulation and energy conservation. However, how these behaviors are expressed in captivity remains unclear. To examine behavioral responses to cold conditions, we analyzed the daily activity rhythms and spatial preferences of R. brelichi under winter conditions. Continuous focal observations and instantaneous scan sampling (every 60 s, 07:00–20:00) were conducted across three consecutive snowy days. The monkeys spent most of their time in sleep, with additional time devoted to awake thermoregulatory behaviors. Spatial use was uneven, with outdoor platform most utilized and indoor ground areas least used. Activity showed distinct daily rhythms, with locomotion peaking in the early morning and evening, and foraging concentrated in the late afternoon. Spatial behavior also displayed cyclical patterns, including consistent outdoor platform use and bimodal reliance on indoor foraging and ground areas. These findings provide the first detailed behavioral and spatial profile of R. brelichi in winter captivity, revealing short-term behavioral adjustments to cold conditions and highlighting constraints imposed by enclosure design. The results offer baseline data for improving welfare and enclosure management for this and other cold-adapted primates. Full article

Reintroductions are essential in wildlife conservation, but their success depends not only on demographic outcomes such as survival and reproduction, but also on behavioral adjustments that determine integration into the wild. The Grey Crowned Crane (Balearica regulorum), an endangered species, has suffered dramatic declines due to habitat loss, disturbance, and illegal capture. In Rwanda, a large-scale amnesty rescued 242 cranes from captivity, with 166 rehabilitated and released into Akagera National Park. This study used GPS-GSM telemetry to investigate post-release movement of reintroduced captive-rescued cranes in comparison with wild individuals. Twenty-one cranes (10 reintroduced, 11 wild) were tracked for 5–1118 days, with 15 individuals meeting criteria for detailed analyses. Reintroduced cranes exhibited reduced dispersal, with only 2 of 7 dispersing compared to 7 of 9 wild cranes, and typically after much longer residence at the release site. Reintroduced cranes also had smaller maximum displacements (median 8.4 km) and smaller home ranges (median 3.3 km²) relative to those of wild cranes (median 24.0 km and median 22.6 km², respectively). These findings suggest that supplemental feeding and extended captivity (2 days to 10 years) of reintroduced cranes strongly influenced their high site fidelity and movement patterns. While limited dispersal may benefit short-term survival, long-term monitoring of survival, reproduction, and demographic trends is critical for assessing whether reintroduction achieves population recovery. Full article

The hypoxic, cold, and high-ultraviolet radiation environments at high altitude pose severe challenges to mammalian immune and metabolic systems. However, little is known about how captive forest musk deer adapt to high-altitude environments and their seasonal variations. This study analyzed peripheral blood transcriptomes of 33 captive forest musk deer (Moschus berezovskii) at high altitude (~3900 m) and low altitude (~1450 m) during autumn-winter and spring-summer seasons. Results revealed comprehensive immune suppression in the high-altitude group during autumn-winter (downregulation of complement system CFB/C2/C3, interferon pathway genes including FLT3, with only natural killer (NK) cell PRKCQ upregulated), coupled with energy-conserving metabolic reprogramming (altered carbohydrate metabolism, inhibited lipid synthesis, fat mobilization, suppressed protein degradation). During spring-summer, neutrophil antimicrobial responses (SLPI/NCF1/ELANE) and humoral immunity (B cell differentiation genes PAX5/RUNX1; class-switch enzyme AICDA) partially recovered while cellular immunity (IL15/B2M) remained suppressed, accompanied by enhanced anabolic metabolism and adipocyte differentiation. Notably, NK cell-mediated cytotoxicity showed selective enhancement despite comprehensive immune suppression, representing an energy-efficient innate defense strategy. This study provides the first characterization of seasonal immune dynamics in a high-altitude cervid species. These findings reveal persistent immune constraints in high-altitude populations and provide theoretical foundations for disease prevention and health management in captive forest musk deer at high altitudes. Full article

The Yellow-spotted Bell Frog, Ranoidea castanea is a critically endangered species, native to the tablelands of New South Wales, Australia. It was rediscovered in 2009, after it had seemingly disappeared thirty years earlier. Upon rediscovery, a conservation breeding program was established at Taronga Zoo in Sydney, Australia, to secure an insurance population of the species. This paper describes the ex situ management and first successful captive breeding of this species, documents its life history data, and provides valuable learning that may benefit other conservation breeding programs. Although initial breeding attempts were unsuccessful whilst founding animals were housed indoors or in small outdoor enclosures, success was achieved between 2017 and 2019, once frogs were moved into a large outdoor enclosure (five clutches in three seasons). The attempted breeding of F1 individuals in an indoor dedicated facility in 2024 had greater success, with 60% of paired females laying eggs (six clutches in one season). Breeding behaviour occurred primarily between October and December, with clutches of unpigmented eggs laid amongst submergent vegetation from late October to mid-November. Overall, the program has resulted in the production of 2162 juvenile frogs for release, in addition to the retention of over 100 frogs for the insurance population. Herein, we provide important life history data for our study species and a framework for conservationists to propagate this species in an ex situ environment. We also highlight other key considerations, such as i) the importance of quickly establishing conservation breeding programs for threatened species and not assuming a targeted species will breed as readily as an analogue species, and ii) underscore the importance of undertaking baseline disease screening in the in situ environment. Full article

Background: Although antivenom is the standard treatment for snakebite envenoming, its efficacy may be impacted by geographic variation in venom composition, emphasizing the need for region-specific antivenom development. Methods: We report a case of snakebite envenoming, in which the patient was bitten on the hand by a captive Malayan pit viper (Calloselasma rhodostoma) with typical clinical manifestations following. Antivenom (produced in Thailand) was administered at 33 and 39 h post-bite. Venom from the causative individual snake was collected for compositional analysis via SDS-PAGE. Enzymatic activity of the venom was evaluated through the degradation of casein and phospholipid substrates, along with the assessment of enzymatic inhibition by two regionally specific antivenoms produced in Vietnam (AV. Cr. VN.) and Thailand (AV. Cr. TL.). Results: The patient showed good recovery, with complete normalization by day 7. SDS-PAGE profiling of the venom revealed five major enzymes, with SVSP, SVMP and PLA₂ being the most abundant (16.7%, 40.11% and 26.11%, respectively). Antivenom inhibition tests revealed remaining casein percentages of 67.43% (AV. Cr. VN) and 59.35% (AV. Cr. TL). Blood agar assays indicated that phospholipase activity was reduced to 21.01% by AV. Cr. VN. and 23.30% by AV. Cr. TL. Conclusions: Our results show that the Vietnamese antivenom generated greater inhibitory activity against proteinases compared to the Thai product, underscoring the importance of using regionally specific antivenoms that are more effective against the venom profiles of locality-matched snake populations. Full article

The Red-legged Partridge (Alectoris rufa, Phasianidae) is a non-migrant gamebird endemic to southwestern Europe that was introduced into Mediterranean and Atlantic islands in historical times. This is the case for Madeira, Portugal, where a population morphologically assigned to A. r. hispanica has been present since the XV century. We assessed its genetic identity using 2248 (Cytochrome-b, Cyt-b + Control Region, CR) and 297 bp-long (CR) mitochondrial DNA sequences obtained from modern and archival (1900–1964, including Caccabis rufa maderensis syntypes) partridges, respectively. These sequences were compared against an already published dataset covering the entire Iberian A. rufa range. We found that all the haplotypes of modern birds from Madeira were private to this island. The putative subspecies was confirmed, and northern Portugal with northwestern Spain turned out to host the closest mainland populations. This result was in line with the origin of the first human settlers of Madeira from, among other historical provinces, Douro Litoral and Minho, the latter neighboring Galicia. Despite relatively recent A. rufa importations from continental Europe, we did not find any significant change over time in the haplotypic pattern of Madeiran partridges as well as any evidence for maternal introgression from species such as the congeneric Chukar Partridge (A. chukar). Studies relying on genome-wide markers and including the only captive-bred population of Madeira are needed to gain more comprehensive information for the management of the local A. rufa. Full article

Since its discovery in 2019, SARS-CoV-2 has continued to be detected in both humans and animals worldwide. Currently there is limited research focusing on serological surveillance of wildlife under human care. Here we tested 230 serum samples of 134 animals from two zoological institutions collected between 2015 and 2024. To assess prior exposure and antibody responses from natural infection or vaccination, we used three serological assays: a nucleocapsid protein-based ELISA (N-ELISA), a surrogate virus neutralization test (sVNT) for spike (S) protein and a neutralization assay with S-pseudotyped viral particles. Among the 114 samples collected from 58 animals at Fort Wayne Zoo in Indiana, 37 samples from 20 vaccinated animals were sVNT-positive, and 2 of the positive animals had 2 samples prior to vaccination that tested positive by N-ELISA. Of the 116 samples from 76 animals at Brookfield Zoo in Illinois, 20 samples of 20 animals were sVNT-positive, and 19 of the positive animals had been vaccinated. Among these 20 sVNT-positive samples, only one sample from a South American Tapir was positive from prior to vaccination and 1 sample from a sloth bear was also positive by N-ELISA, marking the first documented cases of SARS-CoV-2 exposure in both species. Neutralization assays with S-pseudotyped virus revealed that some of the sVNT-positive samples have strong activity against the WH1-S pseudovirus but showed significantly reduced neutralization against the Omicron LP.8.1-S pseudovirus. These results underscore the need for updated vaccines tailored to emerging variants. Overall, our findings highlight the importance of continued serological surveillance across multiple species to detect new SARS-CoV-2 exposures and monitor vaccine-induced immunity in captive animal populations. Full article

The overexploitation of wild populations for the marine ornamental trade necessitates optimized captive breeding, particularly for iconic species like the clownfish Amphiprion ocellaris. This study investigated the social behavior and cognitive abilities of juvenile clownfish in relation to artificial rearing practices. Using modified three-tank tests, we assessed social preference and cognition ability in two size groups: Small-bodied Group (SG: 2.0–2.5 cm) and Large-bodied Group (LG: 3.5–4 cm). The results indicated that clownfish have the following: (a) Strong Social Preference: Both SG and LG exhibited significant preference for areas near conspecifics (SPI > 0), with SG showing significantly higher SPI values than LG. (b) Developmental Stage Differences: SG demonstrated a stronger tendency to cluster tightly near conspecifics. LG showed wider exploration patterns and greater movement. (c) Cognition Ability: SG showed renewed interest towards a novel fish after habituation to a familiar fish, while LG displayed a stronger preference for the familiar fish. These findings suggest that clownfish juveniles possess advanced sociality and basic cognition ability. Furthermore, the observed shift in social interaction preference with developmental stages informs optimal timing for grading practices to minimize artificial rearing stress. This study provides some behavioral insights for optimizing large-scale artificial rearing protocols for clownfish, reducing pressure on wild populations. Full article

Tiger beetles serve as bioindicators of ecosystem health but are under increasing threat from habitat loss and population decline. Ex situ conservation via captive breeding offers promise for species lacking viable wild populations. We evaluated laboratory rearing from egg to adult for eight Korean tiger beetle species to determine the developmental period per developmental stage, mortality rates, larval burrow entrance size, and head–pronotum morphological characteristics under controlled laboratory conditions. High mortality (37.5–80%) occurred during the transition from the pre-pupa to pupa stage, suggesting that mass larval production is needed to offset losses. Reared-type adults of most tiger beetle species tended to be smaller in body length than wild-type adults. Species-specific behaviors (e.g., feeding habits in Cephalota chiloleuca) and the overwintering times of spring–fall and summer species are different, indicating that uniform rearing protocols are suboptimal. Our findings suggest the importance of species-specific adjustment of rearing methods (feeding frequency, overwintering timing) to increase the success of ex situ conservation methods for tiger beetles. In addition, the larval burrow entrance size offered limited utility for species identification in mixed-species habitats, whereas the color of the head and pronotum was considered helpful in identifying some tiger beetle species. Full article

Environmental enrichment (EE) is a vital component of modern zoo husbandry, improving welfare by encouraging natural behaviours and supporting ex situ conservation goals. While EE is widely integrated into the management of many taxa, its welfare benefits remain poorly understood for certain species. The armadillos are examples of such species—underrepresented in research with few targeted EE strategies. Importantly, although olfaction is recognised as their primary sensory modality, methods to promote behaviour linked to olfaction (e.g., exploration and foraging) remain unclear. This review synthesises knowledge on EE for armadillos, using Bloomsmith’s five categories of enrichment and Positive Reinforcement Training (PRT) as a framework. We identify species-typical behaviours to maintain in captivity, consider their ecological relevance in the wild, and explore how tailored EE and PRT can adjust environments. We then evaluate how such approaches can enhance behavioural outcomes, support visitor engagement, and promote welfare critical for in situ and ex situ conservation. Furthermore, we highlight EE’s role in safeguarding adaptive traits for population sustainability and argue that integrating EE and PRT into a broader One Plan Approach provides a pathway for aligning ex situ management with wild ecology. Finally, we identify key gaps, emphasising multi-institutional collaboration, standardised metrics, and long-term research to guide evidence-based practices for armadillos. Full article