BACKGROUND: Hepatozoonosis has been reported in many species around the world. Few incidences have been reported in various species of wild felids. Tigers are endangered large cats and are protected under the Wildlife Protection Act, 1972 under Schedule I. The study was carried out to estimate the positivity rate of hepatozoonosis in tigers of the Vidarbha region of Maharashtra, India.
METHODS: Blood (n = 21) or tissue samples (n = 5) were collected from 26 wild captured / zoo-born or dead tigers during the quarantine period/post-mortem examination. Blood smear examination along with Polymerase Chain Reaction (PCR) studies were conducted for the detection of hepatozoonosis. All the amplicons from the positive samples were purified and sequenced, and the sequences were subjected to nBLAST analysis to detect the species of Hepatozoon. The sequences were deposited into public domain database of National Center for Biotechnology Information (NCBI) and accession numbers were allotted. A phylogenetic study was undertaken to understand the evolutionary lineage of the pathogen. Tissue distribution studies were carried out on tissue samples received during post mortem. A clinical case in a tiger cub was managed and sub-clinical cases were monitored for relapse. Age-wise, sex-wise, region-wise and captive time-wise positivity rate was estimated. The data was analyzed using statistical tools.
RESULTS: A total of 12 tigers were found positive for H. felis during the screening. A clinical case was diagnosed and successfully treated. The age group of 0-3 years reported a positivity rate of 66.66%, and all the cases found positive were reported between the age group of 0-7 years. Males reported a positivity rate of 58.33 per cent, while females reported 35.71%. Taboba and Andhari Tiger Reserve of the state had a positivity rate of 52.94 per cent. However, the statistical analysis for blood parameters and positivity rate by \'t\' test and Chi-squared test were found to be non-significant.
CONCLUSIONS: An overall positivity rate of 46.15% indicates the wide distribution of hepatozoonosis among wild tigers of the Vidarbha region of Maharashtra, India, which is strategically important considering the gene flow and migration of tigers. Hepatozoonosis can progress to clinical outcomes in young animals and require veterinary intervention. Molecular tools and phylogenetic studies can supplement important data on circulating species of Hepatozoon in the field. Further studies on the clinical management and epidemiology of the infection in wild felids will comprehend the cause of wildlife conservation.

The \'landscape of fear\' concept offers valuable insights into wildlife behaviour, yet its practical integration into habitat management for conservation remains underexplored. In this study, conducted in the subtropical monsoon grasslands of Bardia National Park, Nepal, we aimed to bridge this gap through a multi-year, landscape-scale experimental investigation in Bardia National Park, Nepal. The park has the highest density of tigers (with an estimated density of ~7 individuals per 100 km2) in Nepal, allowing us to understand the effect of habitat management on predation risk and resource availability especially for three cervid species: chital (Axis axis), swamp deer (Rucervus duvaucelii) and hog deer (Axis porcinus). We used plots with varying mowing frequency (0-4 times per year), size (ranging from small: 49 m2 to large: 3600 m2) and artificial fertilisation type (none, phosphorus, nitrogen) to assess the trade-offs between probable predation risk and resources for these cervid species, which constitute primary prey for tigers in Nepal. Our results showed distinct responses of these deer to perceived predation risk within grassland habitats. Notably, these deer exhibited heightened use of larger plots, indicative of a perceived sense of safety, as evidenced by the higher occurrence of pellet groups in the larger plots (mean = 0.1 pellet groups m-2 in 3600 m2 plots vs. 0.07 in 400 m2 and 0.05 in 49 m2 plots). Furthermore, the level of use by the deer was significantly higher in larger plots that received mowing and fertilisation treatments compared to smaller plots subjected to similar treatments. Of particular interest is the observation that chital and swamp deer exhibited greater utilisation of the centre (core) areas within the larger plots (mean = 0.21 pellet groups m-2 at the centre vs. 0.13 at the edge) despite the edge (periphery) also provided attractive resources to these deer. In contrast, hog deer did not display any discernible reaction to the experimental treatments, suggesting potential species-specific variations in response to perceived predation risk arising from management interventions. Our findings emphasise the importance of a sense of security as a primary determinant of habitat selection for medium-sized deer within managed grassland environments. These insights carry practical implications for park managers, providing a nuanced understanding of integrating the \'landscape of fear\' into habitat management strategies. This study emphasises that the \'landscape of fear\' concept can and should be integrated into habitat management to maintain delicate predator-prey dynamics within ecosystems.

UNASSIGNED: Driven by habitat loss and fragmentation, large carnivores are increasingly navigating human-dominated landscapes, where their activity is restricted and their behaviour altered. This movement, however, raises significant concerns and costs for people living nearby. While intricately linked, studies often isolate human and carnivore impacts, hindering effective management efforts. Hence, in this study, we brought these two into a common framework, focusing on an interface area between the critical tiger habitat and the human-dominated multiple-use buffer area of a central Indian protected area.
UNASSIGNED: We employed a fine-scale camera trap survey complemented by GPS-collar movement data to understand spatio-temporal activity patterns and adjustments of tigers in response to anthropogenic pressures. We used an occupancy framework to evaluate space use, Bayesian circular GLMs to model temporal activity, and home range and step length analyses to assess the movement patterns of tigers. Further, we used predation-risk models to understand conflict patterns as a function of tiger presence and other habitat variables.
UNASSIGNED: Despite disturbance, a high proportion of the sampled area was occupied by 17 unique tigers (ψ = 0.76; CI [0.73-0.92]). The distance to villages (β ± SE = 0.63 ± 0.21) and the relative abundance of large-bodied wild prey (β ± SE = 0.72 ± 0.37) emerged as key predictors of tiger space use probability, indicating a preference for wild prey by tigers, while human influences constrained their habitat utilisation. Distance to villages was also identified as the most significant predictor of the tigers\' temporal activity (μ ± σ = 3.03 ± 0.06 rad) that exhibited higher nocturnality near villages. A total of 11% of tiger home ranges were within village boundaries, accompanied by faster movement in these areas (displacement 40-82% higher). Livestock depredation probability by tigers increased with proximity to villages (P = 0.002) and highway (P = 0.003). Although tiger space use probability (P = 0.056) and wild prey abundance (P = 0.134) were non-significant at the 0.05 threshold, their presence in the best-fit predation-risk model suggests their contextual relevance for understanding conflict risk. The results highlight the importance of appropriately managing livestock near human infrastructures to effectively mitigate conflict.
UNASSIGNED: Shared space of carnivores and humans requires dynamic site-specific actions grounded in evidence-based decision-making. This study emphasises the importance of concurrently addressing the intricate interactions between humans and large carnivores, particularly the latter\'s behavioural adaptations and role in conflict dynamics. Such an integrated approach is essential to unravel cause-effect relationships and promote effective interface management in human-dominated landscapes.

OBJECTIVE: The Bengal tiger Panthera tigris tigris, is an emblematic animal for Bangladesh. Despite being the apex predator in the wild, their number is decreasing due to anthropogenic activities such as hunting, urbanization, expansion of agriculture and deforestation. By contrast, captive tigers are flourishing due to practical conservation efforts. Breeding within the small captive population can produce inbreeding depression and genetic bottlenecks, which may limit the success of conservation efforts. Despite past decades of research, a comprehensive database on genetic variation in the captive and wild Bengal tigers in Bangladesh still needs to be included. Therefore, this research aimed to investigate the White Bengal tiger genome to create a resource for future studies to understand variation underlying important functional traits.
METHODS: Blood samples from Chattogram Zoo were collected for three white Bengal tigers. Genomic DNA for all collected samples were extracted using a commercial DNA extraction kit. Whole genome sequencing was performed using a DNBseq platform. We generated 77 Gb of whole-genome sequencing (WGS) data for three white Bengal tigers (Average 11X coverage/sample). The data we generated will establish a paradigm for tiger research in Bangladesh by providing a genomic resource for future functional studies on the Bengal white tiger.

A 14-year-old male tiger developed anorexia with elevated blood urea nitrogen and creatinine levels. The patient had a palpable abdominal mass and demonstrated neutrophilic leukocytosis and anaemia. Leukocytes, yeast and bacteria were present in the urine. The animal was non-responsive to therapy and was subsequently euthanised. Extensive acute renal papillary necrosis (RPN) with pyelonephritis, chronic nephritis and polycystic renal disease were evident during gross and microscopic pathology examinations. The histologic occurrence of fungal spores and pseudohyphae morphologically consistent with Candida species were observed within the necrotic papillary regions of the kidney and within multiple foci of mild parakeratotic hyperkeratosis present in the gingiva and tongue. Candida albicans along with a slight growth of Escherichia coli were recovered from kidney cultures. Possible contributory factors for the renal candidiasis and associated RPN include predisposing oral candidiasis, polycystic renal disease, ischaemic nephrosclerosis, age-associated or other forms of immunodeficiency and therapy with meloxicam, a non-steroidal anti-inflammatory drug. The absence of apparent lower urinary tract involvement coupled with the presence of intravascular renal \'Candida emboli\' suggest that chronic oral candidiasis was the probable source of the kidney infection.

Unsustainable trade in big cats affects all species in the genus, Panthera, and is one of the foremost threats to their conservation. To provide further insight into the impact of policy interventions intended to address this issue, we examine the case study of the Republic of Korea (South Korea), which in the early 1990s was one of the world\'s largest importers of tiger (Panthera tigris) bone and a major manufacturer of tiger-derived medicinal products. In 1993, South Korea became a Party to the Convention on International Trade in Endangered Species (CITES) and introduced a ban on commercial trade in CITES Appendix I-listed big cats a year later. We used an expert-based questionnaire survey and an exploration of the CITES trade database to investigate what has since happened to big cat trade in South Korea. Expert opinion suggested that big cat trade has likely substantially reduced since the early 1990s, as a result of the trade ban and broad socioeconomic changes. However, illegal trade has not been eradicated entirely and we were able to confirm that products reportedly derived from big cats were still publicly available for sale on a range of Korean online marketplaces, sometimes openly. The items most commonly reported by respondents from post-1994 trade and supported by expert-led evidence were tiger and leopard (Panthera pardus) skins and tiger bone wine. Although South Korea may provide a useful case study of a historically significant consumer country for tiger which has made strong progress in addressing unsustainable levels of big cat trade within a short period of time, there remains a need to address recalcitrant small-scale, illegal trade. We also recommend further investigation regarding reports of South Korean nationals being involved in illegal trade in tiger-derived products in Southeast Asia.

UNASSIGNED: Escherichia coli is an important intestinal flora, of which pathogenic E. coli is capable of causing many enteric and extra-intestinal diseases. Antibiotics are essential for the treatment of bacterial infections caused by pathogenic E. coli; however, with the widespread use of antibiotics, drug resistance in E. coli has become particularly serious, posing a global threat to human, animal, and environmental health. While the drug resistance and pathogenicity of E. coli carried by tigers and leopards in captivity have been studied intensively in recent years, there is an extreme lack of information on E. coli in these top predators in the wild environment.
UNASSIGNED: Whole genome sequencing data of 32 E. coli strains collected from the feces of wild Amur tiger (Panthera tigris altaica, n = 24) and North China leopard (Panthera pardus japonensis, n = 8) were analyzed in this article. The multi-locus sequence types, serotypes, virulence and resistance genotypes, plasmid replicon types, and core genomic SNPs phylogeny of these isolates were studied. Additionally, antimicrobial susceptibility testing (AST) was performed on these E. coli isolates.
UNASSIGNED: Among the E. coli isolates studied, 18 different sequence types were identified, with ST939 (21.9%), ST10 (15.6%), and ST3246 (9.4%) being the most prevalent. A total of 111 virulence genes were detected, averaging about 54 virulence genes per sample. They contribute to invasion, adherence, immune evasion, efflux pump, toxin, motility, stress adaption, and other virulence-related functions of E. coli. Sixty-eight AMR genes and point mutations were identified. Among the detected resistance genes, those belonging to the efflux pump family were the most abundant. Thirty-two E. coli isolates showed the highest rate of resistance to tetracycline (14/32; 43.8%), followed by imipenem (4/32; 12.5%), ciprofloxacin (3/32; 9.4%), doxycycline (2/32; 6.3%), and norfloxacin (1/32; 3.1%).
UNASSIGNED: Our results suggest that E. coli isolates carried by wild Amur tigers and North China leopards have potential pathogenicity and drug resistance.

Reverse zoonotic transmission events of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been described since the start of the pandemic, and the World Organisation for Animal Health (WOAH) designated the detection of SARS-CoV-2 in animals a reportable disease. Eighteen domestic and zoo animals in Great Britain and Jersey were tested by APHA for SARS-CoV-2 during 2020-2023. One domestic cat (Felis catus), three domestic dogs (Canis lupus familiaris), and three Amur tigers (Panthera tigris altaica) from a zoo were confirmed positive during 2020-2021 and reported to the WOAH. All seven positive animals were linked with known SARS-CoV-2 positive human contacts. Characterisation of the SARS-CoV-2 variants by genome sequencing indicated that the cat was infected with an early SARS-CoV-2 lineage. The three dogs and three tigers were infected with the SARS-CoV-2 Delta variant of concern (B.1.617.2). The role of non-human species in the onward transmission and emergence of new variants of SARS-CoV-2 remain poorly defined. Continued surveillance of SARS-CoV-2 in relevant domestic and captive animal species with high levels of human contact is important to monitor transmission at the human-animal interface and to assess their role as potential animal reservoirs.

There is an urgent need to find a way to improve the genetic diversity of captive South China tiger (SCT, Panthera tigris amoyensis), the most critically endangered taxon of living tigers, facing inbreeding depression. The genomes showed that 13 hybrid SCTs from Meihuashan were divided into two groups; one group included three individuals who had a closer relationship with pureblood SCTs than another group. The three individuals shared more that 40% of their genome with pureblood SCTs and might be potential individuals for genetic rescuing in SCTs. A large-scale genetic survey based on 319 pureblood SCTs showed that the mean microsatellite inbreeding coefficient of pureblood SCTs decreased significantly from 0.1789 to 0.0600 (p = 0.000009) and the ratio of heterozygous loci increased significantly from 38.5% to 43.2% (p = 0.02) after one individual of the Chongqing line joined the Suzhou line and began to breed in the mid-1980s, which is a reason why the current SCTs keep a moderate level of microsatellite heterozygosity and nucleotide diversity. However, it is important to establish a back-up population based on the three individuals through introducing one pureblood SCT into the back-up population every year. The back-up population should be an important reserve in case the pureblood SCTs are in danger in the future.

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