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2.
PeerJ ; 12: e17381, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38726379

RESUMO

Background: 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. Methods: 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. Results: 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%). Conclusions: Our results suggest that E. coli isolates carried by wild Amur tigers and North China leopards have potential pathogenicity and drug resistance.


Assuntos
Escherichia coli , Fezes , Panthera , Tigres , Sequenciamento Completo do Genoma , Animais , Tigres/microbiologia , Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Escherichia coli/isolamento & purificação , Panthera/microbiologia , Fezes/microbiologia , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/microbiologia , Filogenia , Antibacterianos/farmacologia , Genoma Bacteriano/genética , Testes de Sensibilidade Microbiana , China , Virulência/genética , Farmacorresistência Bacteriana/genética , Polimorfismo de Nucleotídeo Único/genética , Tipagem de Sequências Multilocus
3.
PLoS One ; 19(5): e0299783, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748670

RESUMO

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.


Assuntos
Comércio , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , República da Coreia , Animais , Comércio/tendências , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/tendências , Espécies em Perigo de Extinção/legislação & jurisprudência , Espécies em Perigo de Extinção/tendências , Espécies em Perigo de Extinção/estatística & dados numéricos , Tigres , Panthera , Inquéritos e Questionários , Gatos
5.
Sci Rep ; 14(1): 8088, 2024 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582794

RESUMO

The Amur tiger is currently confronted with challenges of anthropogenic development, leading to its population becoming fragmented into two geographically isolated groups: smaller and larger ones. Small and isolated populations frequently face a greater extinction risk, yet the small tiger population's genetic status and survival potential have not been assessed. Here, a total of 210 samples of suspected Amur tiger feces were collected from this small population, and the genetic background and population survival potentials were assessed by using 14 microsatellite loci. Our results demonstrated that the mean number of alleles in all loci was 3.7 and expected heterozygosity was 0.6, indicating a comparatively lower level of population genetic diversity compared to previously reported studies on other subspecies. The genetic estimates of effective population size (Ne) and the Ne/N ratio were merely 7.6 and 0.152, respectively, representing lower values in comparison to the Amur tiger population in Sikhote-Alin (the larger group). However, multiple methods have indicated the possibility of genetic divergence within our isolated population under study. Meanwhile, the maximum kinship recorded was 0.441, and the mean inbreeding coefficient stood at 0.0868, both of which are higher than those observed in other endangered species, such as the African lion and the grey wolf. Additionally, we have identified a significant risk of future extinction if the lethal equivalents were to reach 6.26, which is higher than that of other large carnivores. Further, our simulation results indicated that an increase in the number of breeding females would enhance the prospects of this population. In summary, our findings provide a critical theoretical basis for further bailout strategies concerning Amur tigers.


Assuntos
Leões , Tigres , Animais , Feminino , Tigres/genética , Espécies em Perigo de Extinção , Heterozigoto , Densidade Demográfica , Repetições de Microssatélites/genética , Leões/genética , Conservação dos Recursos Naturais , Variação Genética
6.
Genes (Basel) ; 15(4)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38674333

RESUMO

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.


Assuntos
Espécies em Perigo de Extinção , Repetições de Microssatélites , Tigres , Tigres/genética , Animais , Repetições de Microssatélites/genética , China , Variação Genética , Endogamia , Feminino , Masculino , Conservação dos Recursos Naturais/métodos , Cruzamento
7.
Viruses ; 16(4)2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38675958

RESUMO

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.


Assuntos
Animais de Zoológico , COVID-19 , SARS-CoV-2 , Tigres , Animais , Cães , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/classificação , COVID-19/transmissão , COVID-19/epidemiologia , COVID-19/veterinária , COVID-19/virologia , Tigres/virologia , Gatos , Animais de Zoológico/virologia , Inglaterra/epidemiologia , Humanos , Filogenia , Doenças do Cão/virologia , Doenças do Cão/epidemiologia , Doenças do Cão/transmissão , Zoonoses/virologia , Zoonoses/transmissão , Zoonoses/epidemiologia
8.
J Zoo Wildl Med ; 55(1): 143-154, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38453497

RESUMO

Based upon previous clinical experience with domestic cats (Felis catus), the ability to assess ABC blood types and blood (in-)compatibilities of nondomestic felids, and adequately consider and plan for blood transfusions, may be important. Although nondomestic felids appear to have an ABC blood group system similar to domestic cats, typing with point-of-care kits and by CMAH genotyping for domestic cats have not been reported. In this study, 162 blood samples from 18 different nondomestic felid species (cheetah [Acinonyx jubatus, n = 42], lion [Panthera leo, n = 33], tiger [Panthera tigris, n = 23], Canada lynx [Lynx canadensis, n = 11], snow leopard [Uncia uncia, n = 10], puma [Puma concolor, n = 7], clouded leopard [Neofelis nebulosa, n = 6], serval [Leptailurus serval, n = 5], jaguar [Panthera onca, n = 5], fishing cat [Prionailurus viverrinus, n = 4], Pallas cat [Felis manul, n = 3], bobcat [Lynx rufus, n = 3], ocelot [Leopardus pardalis, n = 3], black footed cat [Felis nigripes, n = 2], leopard [Panthera pardus, n = 2], African wildcat [Felis lybica, n = 1], caracal [Caracal caracal, n = 1], and sand cat [Felis margarita, n = 1]) were ABC blood typed by laboratory and point-of-care tests, genotyped for four known CMAH variants for type B and type C (AB) phenotypes, and crossmatched with one another and domestic type A cats. Traditional tube typing identified blood type A (n = 106), type B (n = 8), type C (n = 43), and no discernible ABC type (n = 4). Several discrepancies were found between point-of-care and traditional typing test results. None of the tested felids possessed the four CMAH variants responsible for type B and C (AB) in domestic cats. Crossmatch incompatibilities (≥2+ agglutination) were identified within and between nondomestic felid species and beyond ABC incompatibilities. Of 26 crossmatches performed between domestic cats and various nondomestic felids, only 7 (27%) were compatible. In conclusion, point-of-care typing kits and CMAH genotyping, successfully used in domestic cats, may not identify the correct ABC blood type in nondomestic felids. Prior crossmatching is recommended to increase the likelihood of compatible transfusions between any nondomestic felids.


Assuntos
Acinonyx , Felidae , Felis , Leões , Lynx , Panthera , Tigres , Gatos , Animais , Genótipo , Panthera/genética
9.
Cell Mol Biol (Noisy-le-grand) ; 70(2): 212-216, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38430018

RESUMO

Tiger energy drink is used in this research to see the effect on serum lipid profile, liver enzymes, and kidney function, also observing changes in sperm parameters. Sixteen male rats were divided into four groups, each consisting of four rats. The control group was given water and rat feed, while groups 1, 2, and 3 were given water with Tiger energy drink (25%, 50%, and 75%, respectively) for eight weeks. The results showed that the effect of energy drinks on lipid profile decreased cholesterol, TG, and LDL, while there was a slight increase in HDL. Treatment with wild Tiger energy drink generally caused insignificant increases in GOT and GPT in both G2 and G3 groups as compared to the control. However, in the G1 group, GPT and GOT significantly increased. Accordingly, ALP concentration was significantly increased in all experimental groups compared to the control group. Sperm quality declined as the concentration of energy drinks consumed increased. The potential adverse effects of energy drinks, at their specific dosages, have been determined to include hepatic and renal impairment, as well as alterations in serum lipids. Additional research is required to investigate the specific mechanism by which energy drinks impact spermatogenesis, either through the modulation of endocrine hormones or other metabolic pathways.


Assuntos
Bebidas Energéticas , Tigres , Ratos , Masculino , Animais , Bebidas Energéticas/efeitos adversos , Sêmen , Espermatozoides , Lipídeos , Água
10.
World J Microbiol Biotechnol ; 40(4): 111, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416247

RESUMO

The gut microbiome refers to the microorganism community living within the digestive tract. The environment plays a crucial role in shaping the gut microbiome composition of animals. The gut microbiome influences the health and behavior of animals, including the critically endangered Malayan tiger (Panthera tigris jacksoni). However, the gut microbiome composition of Malayan tigers, especially those living in their natural habitats, remains poorly understood. To address this knowledge gap, we used next-generation sequencing DNA metabarcoding techniques to analyze the gut microbiome of wild Malayan tigers using fecal samples collected from their natural habitats and in captivity. Our aim was to determine the gut microbiota composition of the Malayan tiger, considering the different types of habitat environments. The results revealed a diverse microbial community within the gut microbiome of Malayan tigers. The prominent phyla that were observed included Firmicutes, Proteobacteria, Actinobacteriota, Fusobacteriota and Bacteroidota. Beta diversity analysis revealed significant differences in gut microbiome composition of Malayan tigers that inhabited oil palm plantations, in villages and protected areas. Diversity analysis also revealed significant difference in the gut microbiome between wild and captive Malayan tigers. However, the distinctions of gut microbiome between wild and captive alpha diversity did not yield significant differences. The differences in microbiome diversity resulted from the interplay of dietary intake and environmental factors. This information will facilitate the establishment of focused conservation approaches and enhance our understanding of the effect of microbiome composition on Malayan tiger health.


Assuntos
Microbioma Gastrointestinal , Microbiota , Tigres , Animais , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , Bacteroidetes
11.
Zoo Biol ; 43(2): 199-204, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38214196

RESUMO

Captive large felines are prone to abnormal repetitive behaviors like pacing, which are associated with welfare issues. Visual contact without the opportunity to engage in appropriate behavior is known to increase pacing. To better understand the relationship between pacing and conspecific visual contact, we investigated this effect by conducting a barrier experiment on a male-female pair of Sumatran tigers (Panthera tigris sumatrae) in Rotterdam Zoo, the Netherlands. The tigers were exposed to four consecutive housing treatments: (i) housed in the same enclosure (baseline), (ii) housed in separate enclosures with visual contact, (iii) housed in separate enclosures without visual contact, and (iv) housed in the same enclosure after the separation. We used focal and scan sampling to measure pacing and recorded the number of visitors. Moreover, we applied scan sampling to measure activity. Overall, our results indicate that the tigers paced significantly more when housed in separate enclosures with conspecific visual contact. Moreover, our results suggest that limiting visual contact between neighboring tigers can mitigate pacing. Implementing these findings in tiger husbandry and enclosure design has the potential to improve animal welfare zoo populations of large felines.


Assuntos
Tigres , Feminino , Masculino , Animais , Gatos , Animais de Zoológico , Bem-Estar do Animal
12.
Sci Rep ; 14(1): 2395, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287072

RESUMO

Recently, the tiger-cat species complex was split into Leopardus tigrinus and Leopardus guttulus, along with other proposed schemes. We performed a detailed analysis integrating ecological modeling, biogeography, and phenotype of the four originally recognized subspecies-tigrinus, oncilla, pardinoides, guttulus-and presented a new multidimensional niche depiction of the species. Species distribution models used > 1400 records from museums and photographs, all checked for species accuracy. Morphological data were obtained from institutional/personal archives. Spotting patterns were established by integrating museum and photographic/camera-trap records. Principal component analysis showed three clearly distinct groups, with the Central American specimens (oncilla) clustering entirely within those of the Andes, namely the pardinoides group of the cloud forests of the southern Central-American and Andean mountain chains (clouded tiger-cat); the tigrinus group of the savannas of the Guiana Shield and central/northeastern Brazil (savanna tiger-cat); and the guttulus group in the lowland forests of the Atlantic Forest domain (Atlantic Forest tiger-cat). This scheme is supported by recent genetic analyses. All species displayed different spotting patterns, with some significant differences in body measurements/proportions. The new distribution presented alarming reductions from the historic range of - 50.4% to - 68.2%. This multidimensional approach revealed a new species of the elusive and threatened tiger-cat complex.


Assuntos
Tigres , Animais , Filogenia , Florestas , Brasil
13.
Zoo Biol ; 43(1): 42-54, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37746904

RESUMO

Numerous facilities around the world offer tourists interactive experiences with captive tigers. Yet, the animal welfare implications of this practice have not been widely studied. This study aimed to investigate whether qualitative behavioral assessment (QBA) could: (i) provide a valid indicator of tiger's emotional state and (ii) be applied to assess whether unfamiliar human presence with hand-raised captive tigers had an impact on the emotional state of those tigers. To investigate this, QBA was applied to video clips of hand-raised captive tigers from three sites (two offering unfamiliar human interaction, Sites A and C, and one retirement site with no direct interactions, Site B) in Thailand. QBA allows inferences to be made about animal emotion on the basis of descriptions of behavioral expression. Analysis, using a free choice profiling methodology, was provided by observers (N = 38) split between three groups; tiger keepers and vets from the Thai venues (n = 12), UK-based animal behavior MSc and vet students (n = 16), and international tiger keepers (n = 10). Tigers (N = 35) were split between Sites A (n = 7), B (n = 18), and C (n = 10) and filmed at three time points; morning (0800-0930 h); midday, (1130-1230 h); and evening, (1630-1830h) totaling 105 clips. Using generalized procrustes analysis, a consensus profile was calculated for each observer group. Two meaningful dimensions of behavioral expression, explaining 75.0% of the variation, were observed across these groups: Dimension 1 (D1: "active"/"interested"/"agitated" to "relaxed"/"calm"/"chilled-out") and Dimension 2 (D2: "bored"/"stressed"/"frustrated" to "relaxed"/"curious"/"interested"). There was clear agreement between the three observer groups in terms of tiger emotional expression along D1. However, agreement was more variable on D2. The behavioral expression on D1 was not significantly affected by site but was significantly affected by an interaction between age and time of day. Time of day also affected scores on D2, with the Thai observer group also showing an effect of site. During the midday period, when unfamiliar humans were present, all tiger age groups showed more positive behavioral expressions on D1 (lower scores: "relaxed"/"calm"/"chilled-out") and more negative behavioral expressions on D2 (higher scores: "bored"/"stressed"/"frustrated"), which could indicate that the presence of unfamiliar humans was a stressor. However, tigers in the retirement Site C also displayed similar behavioral expressions, which could indicate a deeper welfare issue. With further development, QBA could be used as part of a valid tool for long-term measurement of behavioral expression in captive tigers.


Assuntos
Tigres , Humanos , Animais , Tailândia , Turismo , Animais de Zoológico , Comportamento Animal
14.
Anat Histol Embryol ; 53(1): e12973, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37787029

RESUMO

The Bengal tiger (Panthera tigris tigris) is a species belonging to the Felidae family. In Argentina, tigers are currently only found in captivity. The longevity of individual animals in human-controlled environments depends on proper management and practices that prioritize animal welfare. Regular veterinary care is essential to maintain optimal health conditions. Professionals must have a comprehensive understanding of the anatomy and physiology of tigers to effectively perform medical procedures and administer treatments. The study described in the text focuses on the trajectory and distribution of nerves in the pelvic limb of a Bengal tiger specimen, providing detailed dissection findings. The results revealed that the lumbosacral plexus is formed from the ventral rami of the LIV, LV, LVI, LVII, SI, SII and SIII nerves. Among the observations to highlight is the great development of the nerves N. cutaneus femoris lateralis and N. cutaneus femoris caudalis some differences were observed in the distribution of the N. femoralis and N. obturatorius; the N. ischiadicus, together with its division into the fibularis communis and tibialis nerves, showed the same configuration observed in other cats. Finally, it was observed that the nerves N. gluteus cranialis and N. gluteus caudalis also originated from the truncus lumbosacralis. The similarities and differences with studies carried out on other cats are relevant and provide anatomical data for medical procedures in the Bengal tiger.


Assuntos
Tigres , Humanos , Animais , Membro Posterior , Extremidade Inferior , Plexo Lombossacral/anatomia & histologia
16.
In Vivo ; 38(1): 226-234, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38148068

RESUMO

BACKGROUND/AIM: Chronic kidney disease (CKD) is one of the most common causes of mortality in wild non-domestic felidae. The molecular mechanism regulating renal fibrosis in nephropathy is not fully understood especially in the felidae. This study aimed to elucidate senescence marker protein 30 (SMP30) expression patterns and its relationship with epithelial-mesenchymal transition (EMT) by immunostaining in two necropsied Siberian tigers (Panthera tigris altaica) with CKD. MATERIALS AND METHODS: Two kidney samples from male Siberian tigers were fixed and tissue sections were stained for histopathological assay. RESULTS: In CKD, renal tubular epithelial cells lost their tubular structures surrounded by severe interstitial fibrosis and were detached from the basement membrane. These damaged cells resembled the morphology of mesenchymal cells and showed much lower SMP30 expression compared with intact tubular epithelial cells. These cells also expressed vimentin, which is specifically expressed by mesenchymal cells, and through double staining, it was observed that vimentin was expressed in the tubular epithelial cells where SMP30 was not expressed. In addition, double-positive expression of pan-cytokeratin (pan-CK) and vimentin was found in damaged epithelial cells with mesenchymal features. CONCLUSION: We demonstrated possible evidence to understand the role of SMP30 as a new pivotal factor and the possibility of decreased SMP30 as a potential indicator of EMT at the end stage of CKD.


Assuntos
Felidae , Insuficiência Renal Crônica , Tigres , Animais , Masculino , Humanos , Vimentina , Rim , Insuficiência Renal Crônica/genética , Transição Epitelial-Mesenquimal/genética , Fibrose
17.
Dokl Biol Sci ; 512(1): 311-316, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38087019

RESUMO

Polymorphism of nine microsatellite loci in the Sikhote-Alin tiger population was analyzed in the modern and recent historical periods, using blood, excrement, and museum bone samples. Tests for excess heterozygosity to determine whether the population went through a period of low abundance and a low value of the Garza-Williamson coefficient indicated that such events were highly probable to occur in both recent and earlier history. The mean effective population size Ne of a current sample was 34.4 (95% confidence interval 17-106.8). This fact is of great interest in the contest of conservation and restoration of endangered large cat species.


Assuntos
Tigres , Animais , Tigres/genética , Espécies em Perigo de Extinção , Densidade Demográfica , Repetições de Microssatélites/genética , Variação Genética/genética
18.
PeerJ ; 11: e15914, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025689

RESUMO

Background: Large carnivores play a crucial role in maintaining the balance of the ecosystem. Successful conservation initiatives have often led to a huge increase in predators which has often led to negative interactions with humans. Without the knowledge of the carrying capacity of the top predator, such decisions become challenging. Here, we have derived a new equation to estimate the carrying capacity of tigers based on the individual prey species density. Methods: We used tiger densities and respective prey densities of different protected areas. Relative prey abundance was used instead of absolute prey density as this could be a better surrogate of the prey preference. We used a regression approach to derive the species-wise equation. We have also scaled these coefficients accordingly to control the variation in the standard error (heteroscedasticity) of the tiger density. Furthermore, we have extended this regression equation for different species to different weight classes for more generalized application of the method. Results: The new equations performed considerably better compared to the earlier existing carrying capacity equations. Incorporating the species-wise approach in the equation also reflected the preference of the prey species for the tiger. This is the first carrying capacity equation where the individual prey densities are used to estimate the carnivore population density. The coefficient estimates of the model with the comparison with prey-predator power laws also reflect the differential effect of tigers on different prey species. The carrying capacity estimates will aid in a better understanding of the predator-prey interaction and will advance better management of the top predator.


Assuntos
Carnívoros , Tigres , Animais , Humanos , Ecossistema , Conservação dos Recursos Naturais , Densidade Demográfica
20.
Mol Biol Evol ; 40(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37987559

RESUMO

Even in the genomics era, the phylogeny of Neotropical small felids comprised in the genus Leopardus remains contentious. We used whole-genome resequencing data to construct a time-calibrated consensus phylogeny of this group, quantify phylogenomic discordance, test for interspecies introgression, and assess patterns of genetic diversity and demographic history. We infer that the Leopardus radiation started in the Early Pliocene as an initial speciation burst, followed by another in its subgenus Oncifelis during the Early Pleistocene. Our findings challenge the long-held notion that ocelot (Leopardus pardalis) and margay (L. wiedii) are sister species and instead indicate that margay is most closely related to the enigmatic Andean cat (L. jacobita), whose whole-genome data are reported here for the first time. In addition, we found that the newly sampled Andean tiger cat (L. tigrinus pardinoides) population from Colombia associates closely with Central American tiger cats (L. tigrinus oncilla). Genealogical discordance was largely attributable to incomplete lineage sorting, yet was augmented by strong gene flow between ocelot and the ancestral branch of Oncifelis, as well as between Geoffroy's cat (L. geoffroyi) and southern tiger cat (L. guttulus). Contrasting demographic trajectories have led to disparate levels of current genomic diversity, with a nearly tenfold difference in heterozygosity between Andean cat and ocelot, spanning the entire range of variability found in extant felids. Our analyses improved our understanding of the speciation history and diversity patterns in this felid radiation, and highlight the benefits to phylogenomic inference of embracing the many heterogeneous signals scattered across the genome.


Assuntos
Felidae , Tigres , Animais , Filogenia , Felidae/genética , Evolução Biológica , Fluxo Gênico
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