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1.
J Parasitol ; 110(2): 114-126, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38503317

RESUMO

An inventory of parasites infecting the jaguar (Panthera onca) across its distribution range is relevant for the conservation of this threatened big cat. In this study, we report the occurrence of helminths in a jaguar from Mexico using morphological techniques (cleared and stained mounts and scanning electron microscopy) and partial sequences of the 28S ribosomal RNA (28S rRNA) gene and the cytochrome c oxidase 1 mitochondrial (COI) gene. We also provide an updated list of helminth species reported in jaguars in the Americas. Three helminth taxa are identified in the jaguar examined from Mexico: Toxocara cati, Physaloptera sp., and Taenia sp. The new 28S rRNA sequences of To. cati, Physaloptera sp., and Taenia sp. and the COI sequence of Taenia sp. corroborate the identity of the helminths isolated from this host. One hundred and twenty-nine records of helminths parasitizing jaguars from 49 studies up to May 2023 were identified in the Americas. In most of these studies (73.6%), helminths were identified using coproparasitological techniques. Sixteen helminths (7 nematodes, 5 cestodes, 3 acanthocephalans, and 1 trematode) were identified at the species level in free-ranging and captive jaguars. The study demonstrates the value of an integrative taxonomy approach to increase the accuracy of parasite identification in wildlife, especially when helminth specimens are scarce or poorly fixed.


Assuntos
Helmintos , Nematoides , Panthera , Animais , Panthera/genética , México/epidemiologia , RNA Ribossômico 28S/genética , Helmintos/genética
2.
PLoS One ; 19(3): e0300375, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517860

RESUMO

The jaguar (Panthera onca) is a charismatic species considered Vulnerable in Colombia but yet largely unknown in the country. The species is mostly threatened by the continuous decline in its habitats, mostly derived from deforestation and habitat loss, additional to hunting and conflicts with humans. Thus, the future of jaguars in Colombia depends on protecting and recovering existing habitats. The aims of this study were to 1) evaluate jaguar distribution and identify the remnant patches of habitat in Colombia, 2) define an ecological connectivity network within the country, and 3) propose a priority areas portfolio for the conservation and recovery of jaguars. We used a presence background model for estimating species potential distribution and subsequently identified remaining habitat patches across the country based on land cover and species-specific ecological attributes. We then created an ecological connectivity network based on circuit theory and following a multi-criteria approach identified jaguar priority areas for conservation (JPCA) and recovery (JPRA). Jaguar potential distribution comprises 1103122.43 km2, from which 56.71% maintain suitable patches of potential habitat. We identified 960 corridors between remnant patches of natural or semi-natural vegetation. Based on the criteria, JPCAs with greater importance were identified in each of the five Colombian regions. JPRAs were located mainly towards the Andean and Caribbean regions. These JPCAs and JPRAs could serve as a guide for designing and implementing management strategies for the long-term conservation and recovery of the species in Colombia.


Assuntos
Panthera , Animais , Humanos , Colômbia , Conservação dos Recursos Naturais , Ecossistema , Região do Caribe
3.
Mol Ecol ; 33(5): e17263, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38318732

RESUMO

The absence of robust interspecific isolation barriers among pantherines, including the iconic South American jaguar (Panthera onca), led us to study molecular evolution of typically rapidly evolving reproductive proteins within this subfamily and related groups. In this study, we delved into the evolutionary forces acting on the zona pellucida (ZP) gamete interaction protein family and the sperm-oocyte fusion protein pair IZUMO1-JUNO across the Carnivora order, distinguishing between Caniformia and Feliformia suborders and anticipating few significant diversifying changes in the Pantherinae subfamily. A chromosome-resolved jaguar genome assembly facilitated coding sequences, enabling the reconstruction of protein evolutionary histories. Examining sequence variability across more than 30 Carnivora species revealed that Feliformia exhibited significantly lower diversity compared to its sister taxa, Caniformia. Molecular evolution analyses of ZP2 and ZP3, subunits directly involved in sperm-recognition, unveiled diversifying positive selection in Feliformia, Caniformia and Pantherinae, although no significant changes were linked to sperm binding. Structural cross-linking ZP subunits, ZP4 and ZP1 exhibited lower levels or complete absence of positive selection. Notably, the fusion protein IZUMO1 displayed prominent positive selection signatures and sites in basal lineages of both Caniformia and Feliformia, extending along the Caniformia subtree but absent in Pantherinae. Conversely, JUNO did not exhibit any positive selection signatures across tested lineages and clades. Eight Caniformia-specific positive selected sites in IZUMO1 were detected within two JUNO-interaction clusters. Our findings provide for the first time insights into the evolutionary trajectories of ZP proteins and the IZUMO1-JUNO gamete interaction pair within the Carnivora order.


Assuntos
Caniformia , Carnívoros , Panthera , Animais , Masculino , Receptores de Superfície Celular/genética , Proteínas do Ovo/genética , Proteínas do Ovo/química , Proteínas do Ovo/metabolismo , Sêmen/metabolismo , Interações Espermatozoide-Óvulo/genética , Carnívoros/genética , Caniformia/metabolismo , Feliformes/metabolismo , Panthera/metabolismo , Zona Pelúcida/metabolismo
4.
Parasitol Res ; 123(1): 88, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38190005

RESUMO

Trypanosoma evansi is a widespread and neglected zoonotic parasite that affects domestic and wild animals, causing a disease commonly known as "surra." The Brazilian Pantanal wetland is recognized as an enzootic area for this protozoan, yet recognizing the importance of reservoir hosts also in order to prevent zoonotic outbreaks. This study aimed to assess the occurrence of T. evansi in jaguars (Panthera onca) from the Brazilian Pantanal wetland and explore associated clinical and hematological manifestations. A total of 42 animals were screened by PCR and sequenced for species identification when positive. Trypanosoma evansi was detected in six free-ranging jaguars (six positive animals of 42 captures and 16 recaptures), representing the first molecular evidence of such infection in this animal species. Our findings suggest that jaguars may act as reservoir hosts of T. evansi in the Brazilian Pantanal wetland. The better understanding of the role of wildlife in the epidemiology of T. evansi is also of importance to future reintroduction and translocation programs toward wildlife conservation efforts.


Assuntos
Panthera , Trypanosoma , Animais , Brasil/epidemiologia , Áreas Alagadas , Trypanosoma/genética , Animais Selvagens
5.
Vet Res Commun ; 48(3): 1779-1784, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38231369

RESUMO

Over nearly 12 years, we collected ticks from free-ranging jaguars (Panthera onca) and performed statistical analyses to comprehend the vector-host relationship throughout the seasons. We evaluated the presence and number of ticks, as well as their association with weight, age, and gender of captured jaguars in the Pantanal and Amazon biomes. Out of 100 captured jaguars (comprising 72 initial captures and 28 recaptures, with 41 females and 31 males), 77 were found to be infested by different tick species. We gathered a total of 1,002 ticks, categorized by the following species in descending order of abundance: Amblyomma sculptum, Amblyomma ovale, Rhipicephalus microplus, Amblyomma triste, Amblyomma cajennense sensu stricto, Amblyomma incisum, and Amblyomma spp. larvae. Apart from weight, statistical analysis indicated that age, gender and seasonality does not significantly affect the presence of different tick species in free ranging jaguars. Notably, A. sculptum adults were more abundant in the first semester, while A. sculptum nymphs and Amblyomma spp. larvae were mainly found during dry months, aligning with their expected life cycle stages. This is the first long-term study in jaguars to correlate seasonality and host factors and also the first time an adult of A. incisum is reported infesting a jaguar.


Assuntos
Amblyomma , Panthera , Estações do Ano , Infestações por Carrapato , Animais , Feminino , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Masculino , Amblyomma/fisiologia , Panthera/fisiologia , Panthera/parasitologia , Brasil , Interações Hospedeiro-Parasita , Ninfa/fisiologia , Ninfa/crescimento & desenvolvimento , Ixodidae/fisiologia
6.
Parasitol Res ; 122(12): 2951-2956, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37823992

RESUMO

Nematode species of the genus Dracunculus (Spirurida: Dracunculoidea) infect tissues and body cavities of reptiles, domestic and wild carnivores, and humans. The definitive hosts acquire the infection by ingesting intermediate (i.e., cyclopoid copepod) or paratenic (i.e., amphibians and fishes) hosts. Here we report the jaguar (Panthera onca) as a potential new host for Dracunculus sp. The nematode was collected from an ulcerated cutaneous nodule on the left anterior limb of a female jaguar in the municipality of Miranda, Mato Grosso do Sul state, Brazil. Based on the morphology of first stage larvae collected from a small fragment of the uterus of the adult nematode, the species was identified as Dracunculus sp. Reichard, 1759. Additionally, the morphological identification was molecularly confirmed by sequencing the cox1 gene. This report advocates for further investigations into the transmission cycle of this parasite in the Brazilian Pantanal wetland, considering the role of wildlife hosts and the zoonotic potential of Dracunculus species in that area.


Assuntos
Dracunculoidea , Panthera , Animais , Humanos , Feminino , Animais Selvagens , Dracunculus , Peixes , Brasil
7.
J Comp Pathol ; 204: 51-54, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37451060

RESUMO

A 7-year-old captive female jaguar (Panthera onca) was presented with a 7-day history of dyspnoea and weight loss. Clinical examination revealed hepatomegaly and elevated serum alanine aminotransferase activity. Pulmonary ultrasonography revealed comet-tail images and an alveolar pattern was detected on thoracic radiography. Due to the poor prognosis, the jaguar was euthanized after 10 days. At necropsy, the main gross findings were hepatomegaly, splenomegaly and multifocal to coalescent, slightly elevated grey areas in the lungs. Histological examination revealed neoplastic proliferation of pleomorphic histiocytes arranged in cohesive sheets in the lungs, liver, spleen, kidneys and lymph nodes. Neoplastic cells had intense immunolabelling for vimentin and ionized calcium-binding adaptor molecule 1, and were immunonegative for pancytokeratin, E-cadherin, CD20, CD3 and CD79α. These findings were compatible with a systemic histiocytic disorder, distinct from any well-defined histiocytic proliferative disease in domestic animals.


Assuntos
Panthera , Animais , Feminino , Hepatomegalia/veterinária , Histiócitos , Autopsia/veterinária , Animais de Zoológico
8.
Arq. bras. med. vet. zootec. (Online) ; 75(4): 696-702, July-Aug. 2023. graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1447352

RESUMO

Lead is a heavy metal and an important cause of acute or chronic toxicosis in humans, domestic, and wild animals. This report aims to describe a case of chronic lead poisoning in a jaguar (Panthera onca) kept under human care that was rescued from the wild environment. The animal was rescued in poor condition in 2004 and kept under human care at the Belo Horizonte Zoological Garden (Minas Gerais, Brazil) until 2020, when it presented with anorexia, vomiting and ataxia. Over the past years the animal had episodes of anemia and increased serum urea and creatinine. Radiography demonstrated 21 radiopaque projectiles on the right side of the face. At necropsy there were multiple projectiles surrounded by fibrous tissue in the subcutaneous of the right side of the face, fibrinous peritonitis, multiple gastric ulcers, and melena. The lead dosage was performed using the atomic absorption spectrometry technique using renal tissue collected at necropsy, with a result of 908 ppb (µg/kg). The findings of projectiles associated with the dosage of lead above the reference limits allow the diagnosis of chronic intoxication in this case.


Chumbo é um metal pesado e uma causa importante de toxicose crônica no homem e em animais domésticos e selvagens. Este relato teve como objetivo descrever um caso de intoxicação crônica por chumbo em uma onça-pintada (Panthera onca), mantida sob cuidados humanos, que foi resgatada de seu ambiente natural em 2004, em pobre condição corporal. O animal foi encaminhado ao zoológico de Belo Horizonte (MG, Brasil), onde permaneceu até 2020, quando desenvolveu anorexia, vômitos e ataxia. Durante os últimos anos, o animal teve episódios de anemia e aumento da concentração sérica de ureia e creatinina. O exame radiográfico demonstrou 21 projéteis radiodensos na face direita. À necropsia, foram observados vários projéteis envoltos por tecido conjuntivo no subcutâneo da face esquerda, peritonite fibrinosa, múltiplas úlceras gástricas e melena. A concentração de chumbo foi determinada por espectrometria de absorção atômica em amostras de tecido renal, indicando 908 ppb (µg/kg). O achado de projéteis de chumbo associado à elevada concentração de chumbo é compatível com intoxicação crônica por chumbo neste caso.


Assuntos
Animais , Panthera , Intoxicação por Metais Pesados/veterinária , Intoxicação por Chumbo/veterinária
9.
J Wildl Dis ; 59(1): 12-23, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36762840

RESUMO

Human activities such as habitat degradation and fragmentation threaten biodiversity in Neotropical areas. This work proposes an analytical methodology to identify natural areas in Central America with anthropogenic impact, analyzing the presence of antimicrobial resistance genes (ARGs) in accordance with their theoretical relationship with human-related activities. Sixteen ARGs were quantified in feces of different individuals of 13 jaguars (Panthera onca) and 13 pumas (Puma concolor) in three conservation areas in Costa Rica by real-time PCR. At least one ARG was detected in all samples. Of the ARGs encoding tetracycline resistance, the most frequent were tetQ and tetY (85% and 69%, respectively). The sulfonamides (sulI and sulII; 69% each), phenicols (catI and catII; 19% and 54%, respectively), and quinolones (qnrS; 12%) were also detected. The presence of human settlements, livestock farms (pigs, cattle, and poultry), roads, human health centers, flood zones, and rivers were identified within each area to generate an index of human activity. We found no difference between the presence of ARG by roads, agricultural activities, and human settlements (P>0.05). However, tetW showed higher percentages with porcine and bovine farms; both tetY and tetW were more frequent in jaguars than in pumas. Of concern is that many of the most contaminated samples were taken from national parks, such as Braulio Carrillo and Tortuguero, where animals should not have direct contact with humans.


Assuntos
Panthera , Puma , Animais , Humanos , Bovinos , Suínos , Antibacterianos , Efeitos Antropogênicos , Farmacorresistência Bacteriana , Ecossistema
10.
Commun Biol ; 6(1): 132, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792802

RESUMO

Jaguars (Panthera onca) exert critical top-down control over large vertebrates across the Neotropics. Yet, this iconic species have been declining due to multiple threats, such as habitat loss and hunting, which are rapidly increasing across the New World tropics. Based on geospatial layers, we extracted socio-environmental variables for 447 protected areas across the Brazilian Amazon to identify those that merit short-term high-priority efforts to maximize jaguar persistence. Data were analyzed using descriptive statistics and comparisons of measures of central tendency. Our results reveal that areas containing the largest jaguar densities and the largest estimated population sizes are precisely among those confronting most anthropogenic threats. Jaguars are threatened in the world's largest tropical forest biome by deforestation associated with anthropogenic fires, and the subsequent establishment of pastures. By contrasting the highest threats with the highest jaguar population sizes in a bivariate plot, we provide a shortlist of the top-10 protected areas that should be prioritized for immediate jaguar conservation efforts and 74 for short-term action. Many of these are located at the deforestation frontier or in important boundaries with neighboring countries (e.g., Peruvian, Colombian and Venezuelan Amazon). The predicament of a safe future for jaguars can only be ensured if protected areas persist and resist downgrading and downsizing due to both external anthropogenic threats and geopolitical pressures (e.g., infrastructure development and frail law enforcement).


Assuntos
Conservação dos Recursos Naturais , Panthera , Animais , Conservação dos Recursos Naturais/métodos , Brasil , Ecossistema , Densidade Demográfica
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