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BACKGROUND/OBJECTIVE: The cestode Echinococcus granulosus causes cystic echinococcosis, a zoonotic parasitic infection that constitutes a significant public health risk. This parasite has been documented to have potential reservoirs and carriers among wild canids, namely wolves, foxes and jackals. This study aimed to determine the prevalence and molecular characteristics of E. granulosus sensu lato species/genotypes among wild canids in three northern, northeastern and north-western Iran regions. METHODS: From 2019 to 2022, 93 wild canid carcasses (69 jackals), (22 foxes) and (2 wolves) were collected that were killed in car accidents or illnesses. Analyses of morphology and morphometry were performed to verify the presence of E. granulosus. To determine E. granulosus s.l. species/genotypes, polymerase chain reaction (PCR)-RFLP (ITS1) was performed utilizing the Bsh1236I (BstUI) restriction enzyme. COX1, NADH1 and ITS1 gene sequencing were also performed to confirm the PCR-RFLP results. RESULTS: During this study, 93 wild canids were examined, and 3.2% (95% CI: 0%-7%) of the 93 were infected with Echinococcus. The north-western region of Iran showed two out of 30 jackals (6.6%) infected with adult Echinococcus compared to one out of 35 jackals (2.8%) in the northern region. DNA from Echinococcus was detected in these individuals by PCR. Based on PCR-RFLP analysis of the ITS1 gene and sequencing of COX1, NADH1 and ITS1 gene, E. granulosus sensu stricto genotype was confirmed in the jackals that had been infected. CONCLUSION: Evidence shows that E. granulosus occurs in jackals in Iran, with the E. granulosus s.s. genotype being the most common. This parasite has been identified as a zoonotic parasite with a genotype that can be transmitted to livestock and humans. Establishing effective control measures to prevent the spread of echinococcosis and ensure public health is crucial.
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Equinococose , Echinococcus granulosus , Genótipo , Animais , Echinococcus granulosus/genética , Irã (Geográfico)/epidemiologia , Equinococose/veterinária , Equinococose/epidemiologia , Equinococose/parasitologia , Chacais/parasitologia , Raposas/parasitologia , Lobos/parasitologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Polimorfismo de Fragmento de RestriçãoRESUMO
This study aimed to molecularly characterize the Hepatozoon spp. infecting domestic and wild dogs in Brazil. A total of 22 whole blood samples tested positive for Hepatozoon spp., and five samples were sequenced for the 18S rDNA gene from H. canis after PCR amplification with four primer sets. Phylogenetic analysis using Bayesian inference showed that the three H. canis isolates from domestic dogs were not monophyletic; however, they were more closely related to each other than to other H. canis sequences. The isolate from the hoary fox (Lycalopex vetulus) was phylogenetically more distant. Two haplotype networks were constructed, identifying 10 haplotypes of H. canis in Brazil, with H10 constituting the largest group. It contains nine isolates, including three from domestic dogs. The H5 haplotype grouped the sequence of L. vetulus with two additional sequences from hosts Tapirus terrestris and L. vetulus, representing the sole haplotype with wild hosts. Bayesian analysis suggested the possible existence of two genetic groups of H. canis in Brazil, indicating gene flow of this agent within the country. These findings contribute valuable insights for a more comprehensive understanding of the molecular diversity of Hepatozoon spp. in Brazil and may help in the development of effective control measures.
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Canidae , Coccidiose , Doenças do Cão , Eucoccidiida , Animais , Cães , Filogeografia , Coccidiose/epidemiologia , Coccidiose/veterinária , Filogenia , Brasil/epidemiologia , Teorema de Bayes , Eucoccidiida/genética , Doenças do Cão/epidemiologiaRESUMO
Wolves were the first animal species to become domesticated by humans, approximately 30,000-50,000 years ago. Human-directed dog breeding over thousands of generations has generated more than 350 recognized breeds displaying surprisingly different phenotypes with respect to morphology, behavior and disease predispositions. The domestication of wolves and the subsequent breeding of dogs can be viewed as one of humankind's oldest and largest genetic experiments and provides us with unique opportunities for research. Dogs have not only become human's best friend but were also described as geneticists' best friend in a past issue of Science. In recognition of the importance of canine genetics, this Special Issue, entitled "Canine Genetics 2", was compiled. It represents a sequel to the former Special Issue "Canine Genetics", which was published in 2019. During the last 15 years, the canine community has heavily relied on a reference genome derived from the female Boxer Tasha. "Canine Genetics 2" includes an article describing a greatly improved version of this important community resource. This Special Issue further contains several reports related to monogenic or complex inherited diseases in dogs. Finally, important aspects of wild canid research, genetic diversity in different populations and canine morphology were investigated.
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Canidae , Lobos , Animais , Cães , Feminino , Humanos , Lobos/genética , Genoma , Fenótipo , Cruzamento , Domesticação , Canidae/genéticaRESUMO
The global threat of neglected tropical diseases (NTDs) constitutes a public health issue in underdeveloped countries. Zoonotic helminthiases are the most common human NTD agents in developing countries in sub-Saharan Africa, Asia, and the Americas, causing a global burden of disease that exceeds that of more recognized infectious diseases such as malaria and tuberculosis. Wild canids are well-known mammals that act as natural reservoirs of zoonotic-relevant helminthiasis worldwide, thus playing a pivotal role in their epidemiology and transmission to humans. Here we evaluate the occurrence of zoonotic gastrointestinal helminths in two Neotropical wild canid species from the Amazonian and Andean regions of Colombia, i.e., the bush dog (Speothos venaticus) and the crab-eating fox (Cerdocyon thous). We recovered tapeworm proglottids from bush dog fecal samples and identified them molecularly as the canine-specific lineage of Dipylidium caninum by using cytochrome c oxidase subunit I (cox1) gene sequences. Moreover, examination of a crab-eating fox during necropsy revealed the presence of non-embryonated eggs of the neglected nematode Lagochilascaris cf. minor, in addition to eggs and gravid proglottids of the cestode Spirometra mansoni. These findings represent the first report of zoonotic-relevant cestodes, i.e., D. caninum ("canine genotype"), S. mansoni, and the nematode L. cf. minor, in bush dogs and crab-eating foxes as final hosts. The occurrence of these zoonotic helminthiases in wild canid species calls for regular monitoring programs to better understand the epidemiology and transmission routes of neglected dipylidiasis, lagochilascariosis, and sparganosis in South America.
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The canine distemper virus (CDV), a paramyxovirus that is closely related to the human measles virus and rinderpest virus of cattle, is a highly contagious viral disease in dogs and wild carnivores worldwide. CDV represents a serious threat to domestic and wild animals, especially to the conservation of endangered wild carnivores. Our study aims to investigate the occurrence of CDV in free-living wild canines in Croatia. For this purpose, 176 red foxes and 24 jackal brain samples collected in the frame of the active surveillance of rabies during winter 2021/2022 were tested. This study provided the first comprehensive overview of the prevalence and spatial distribution of CDV in the wildlife of Croatia, including the molecular phylogenetic analysis of the H gene sequence of field CDV strains circulating in red fox and jackal populations of Croatia. The molecular characterization of hemagglutinin gene genomic regions confirmed the phylogenetic clustering of obtained sequences into the Europa 1 genotype. The obtained CDV red fox sequences were mutually very similar (97.60%). This study indicates the high genetic similarity of Croatian CDV red fox sequences and CDV red fox sequences from Italy and Germany, badger sequences from Germany, polecat sequences from Hungary, and dog sequences from Hungary and Germany.
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Gastrointestinal nematodes and protozoa and other parasite occurrences were evaluated in free-ranging wolf (Canis lupus italicus) and red fox (Vulpes vulpes) populations from natural and anthropized areas of Central Italy. Analyzed fecal samples were collected from 60 foxes and 40 wolves in the anthropized areas, and 41 foxes and 39 wolves in the natural areas. In foxes, hookworm infections (p < 0.0001) were more frequently recorded in the anthropized environment, while coccidia (p < 0.05) and Cryptosporidium spp. (p < 0.0001) were more frequent in the natural area. In wolves, a higher frequency of hookworms (p < 0.0001) was observed in natural areas, while coccidia were more common in the anthropized area (p < 0.05). Moreover, in the natural environment, trichuroid nematodes (p < 0.0001) were significantly more frequent in wolves than in foxes, while Cryptosporidium (p < 0.001) and Giardia duodenalis (p < 0.001) were more common in foxes. In the anthropic area, the occurrence of hookworms was found to be significantly higher in foxes (p < 0.0001), while trichuroid nematodes were more common in wolves (p < 0.0001). The obtained data are indicative of a different diffusion of specific parasite taxa in wolves and foxes living in the natural and/or anthropized environments examined herein.
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Wild canids, as well as other wild animal species, are largely exposed to bites by ticks and other hematophagous vectors where the features favoring their presence and spread are found in wooded and semi-wooded areas. Much of the information about arthropod-borne infections concerns domestic and companion animals, whereas data about these infections in wild canids are not exhaustive. The present study is a narrative review of the literature concerning vector-borne infections in wild canids, highlighting their role in the epidemiology of arthropod-borne bacteria and protozoa.
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Canine distemper outbreak and coinfections in three giant anteaters and in a maned wolf has been described. Three giant anteaters developed respiratory and digestive clinical signs after the introduction of a maned wolf to a Wildlife Rehabilitation Center. The maned wolf and two anteaters died, and one anteater was euthanized. Post mortem and histopathologic exams revealed lesions associated with numerous intraepithelial inclusion bodies, mainly in the respiratory and digestive systems. Infection by distemper virus was confirmed in all animals by RT-PCR and gene sequencing, which revealed the Europe 1/ South America 1 strain, closely related to the strain from Canis familiaris. In addition to distemper, the animals had other comorbidities, such as toxoplasmosis and salmonellosis in the maned wolf and cutaneous candidiasis in an anteater. Considering the chronology of clinical manifestation in both species and the viral characterization, it is possible that the maned wolf was the source of infection to the anteaters. This study demonstrates the importance of implementing biosecurity measures in enclosures that house animals of different species, highlighting the importance of quarantine before introduction of new animals into the same environment.
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Canidae , Coinfecção , Cinomose , Animais , Coinfecção/veterinária , Surtos de Doenças , Cinomose/epidemiologia , Cães , VermilinguaRESUMO
Canis lupus familiaris (domestic dog) represents a reliable sentinel for the occurrence of a well-established transmission cycle of Trypanosoma cruzi among wild mammals in the surroundings and, consequently, where the risk of human infection exists. Serological diagnosis is the chosen method to identify T. cruzi infection in dogs that, in Brazil, rarely present positive parasitological tests. The use of recombinant chimeric parasitic antigens results in a sensitive and specific serological diagnostic test in contrast to the use of crude T. cruzi antigens. Our objective was to evaluate the Chagas/Bio-Manguinhos Lateral Flow Immunochromatographic Rapid Test (Chagas-LFRT) for the diagnosis of T. cruzi infection in domestic dogs and the potential of application of this diagnostic platform to wild canid species. Two recombinant proteins (IBMP-8.1 and IBMP-8.4) that displayed the best performance in the enzyme immunoassay (ELISA) in previous studies were tested in a platform with two diagnostic bands. A panel of 281 dog serum samples was evaluated: 133 positive for T. cruzi by serological diagnosis, including 20 samples with positive blood cultures belonging to different discrete typing units (DTUs); 129 negative samples; and 19 samples from dogs infected by other trypanosomatids: Leishmania infantum, Trypanosoma rangeli, Trypanosoma caninum and Crithidia mellificae, in addition to samples infected by Anaplasma platys, Dirofilaria immitis and Erlichia sp. that were employed to evaluate eventual cross-reactions. We also evaluated the Chagas-LFRT to detect T. cruzi infection in 9 serum samples from six wild canid species. We observed that the intensity pattern of the bands was directly proportional to the serological titer observed in IFAT. The sensitivity was 94%, the specificity was 91% according to the ROC curve, and the defined cutoff was an optical density of 4.8. The agreement obtained was considered substantial by the kappa analysis (84%). From T. cruzi positive hemoculture samples, 88.9% were positive by Chagas-LFRT. The test was efficient in recognizing infections by five of the six T. cruzi DTUs. Cross-reactions were not observed in infections by L. infantum, T. rangeli, T. caninum and D. immitis; however, they were observed in sera of dogs infected by Crithidia mellificae, Anaplasma sp. and Erlichia sp. A strong reaction was observed when serum samples from wild canids were submitted to the Protein A affinity test, confirming its applicability for these species. This test will allow rapid preventive actions in areas with high risk to the emergence of Chagas disease in a safer, reliable, low-cost and immediate manner, without the need for more complex laboratory tests.
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Doença de Chagas , Leishmania infantum , Trypanosoma cruzi , Animais , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Cães , Ensaio de Imunoadsorção Enzimática , Mamíferos , Testes SorológicosRESUMO
Parasites are natural components of ecosystems and play a significant role in the dynamics of wild animal populations. Although the environment of parasites is primarily defined by the host, most life cycles involve stages that must endure external conditions. Rainfall and flooding events are important factors that might influence the transport of parasitic stages, altering soil moisture levels, and resulting in a favorable environment for parasite survival and development. We assessed whether an extraordinary flood event modified the occurrence of gastrointestinal parasites (nematodes and protozoa) in wild canids in two protected areas in northern Argentina. From 2016 to 2018, we collected fecal samples of two fox species, Lycalopex gymnocercus and Cerdocyon thous, and examined the presence of nematodes and protozoa. We assessed changes in the occurrence of these parasites after a flood event, while adjusting for potential confounders (i.e., monthly average temperature, season, host species, site). In a second stage of the analysis, we evaluated whether part of the effect was caused by changes in soil moisture, by adding normalized difference water index as an independent variable. We found that the presence of nematodes in foxes was higher after flooding than before flooding, and this association was not explained by changes in the soil moisture. On the other hand, the flood event was not relevant for protozoa. Stronger and long-lasting flood events are expected due to the effect of global warming on El Niño events, and this may increase and intensify the spread of some parasites affecting wildlife, which could also be of public health concern.
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Helmintos , Parasitos , Animais , Animais Selvagens , Argentina/epidemiologia , Ecossistema , Inundações , RaposasRESUMO
A senile male captive bush dog (Speothos venaticus) presented a small perianal cutaneous nodule. Histologically, there was an ulcerated round cell tumor composed of well differentiated mast cells with abundant intracytoplasmic purple Giemsa-positive granules, with a diffuse eosinophilic infiltrate. Immunohistochemistry revealed that 30% of the neoplastic cells were positive for Kit in the cytoplasm and cell membrane, and all neoplastic cells were negative for MAC and CD3. Less than 10% of the neoplastic cells were positive for Ki67. At necropsy other primary tumors were identified in this animal, including an intestinal adenoma, an adrenal cortex adenoma and a testicular interstitial cell tumor.(AU)
Um cachorro-vinagre (Speothos venaticus) apresentou um nódulo cutâneo pequeno na região perianal. Histologicamente havia neoplasia cutânea de células redondas e ulcerada, constituída por mastócitos bem diferenciados, com abundantes grânulos citoplasmáticos metacromáticos na coloração de Giemsa e infiltrado eosinofílico difuso. A imuno-histoquímica demonstrou que 30% das células neoplásicas eram positivas para a proteína Kit no citoplasma e na membrana celular. As células foram negativas para MAC e CD3. Menos de 10% das células neoplásicas foram positivas para Ki67. Durante a necropsia, foram identificados outros tumores primários, como adenoma intestinal, adenoma cortical da adrenal e tumor de células intersticiais do testículo.(AU)
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Canidae , Mastocitoma Cutâneo/diagnóstico , Mastocitoma Cutâneo/patologia , Adenoma/patologia , Animais de ZoológicoRESUMO
Brucella abortus, B. canis, and pathogenic Leptospira are zoonotic pathogens that infect humans, as well as domestic and wild animals. In wild canids, they may affect their fertility and reproduction, threatening their conservation. Wild canids play a crucial role in the environment as meso- and top-predators and environmental sentinels for zoonotic pathogens. In Chile, three species of wild canids are present, and due to changes in land use and environmental dynamics, it is of utmost relevance to determine the role of these species in the epidemiology of brucellosis and leptospirosis. This study aimed to detect the exposure to B. abortus, B. canis, and pathogenic Leptospira by serologic, bacteriologic, and molecular techniques in native foxes from rehabilitation and exhibition centers in Central Chile. Forty-six blood samples were obtained from Lycalopex culpaeus and L. griseus, detecting 10.9% of seropositivity to B. canis and 7.7% to L. Javanica. No seropositivity was seen for B. abortus. Exposure was not registered by culture and qPCR in any of the sampled animals. Our findings are the first register of exposure to any Brucella species in wild canids in Chile and highlight the need to establish surveillance programs of these emerging pathogens.
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Rangelia vitalii is a protozoan parasite that causes a hemorrhagic and hemolytic disease in dogs known as rangeliosis. Current reports of the disease are concentrated in the southern and southeastern regions of Brazil, as well as in Uruguay, Argentina, and Paraguay, and mainly concern domestic dogs. South American wild canids, such as the crab-eating fox (Cerdocyon thous), the pampas fox (Lycalopex gymnocercus), and the maned wolf (Chrysocyon brachyurus) may also be affected, although existing reports are restricted to Brazil. The present study aimed to detect R. vitalii parasitism in the Uruguayan wild fox population. DNA extracted from the blood and/or spleen samples of road-killed C. thous and L. gymnocercus found in northern Uruguay were subjected to polymerase chain reaction (PCR) to amplify a 551-bp fragment of the Rangelia 18S rRNA gene. A total of 62 wild canids, including 38 C. thous and 24L. gymnocercus, were analyzed. Five crab-eating fox samples (13.2%) were positive for R. vitalii, with 99.5-100% identity between the sequences. All samples from pampas fox tested negative for R. vitalii. When compared with the R. vitalii sequences available in GenBank, a similarity of 98.9-100% was revealed. Molecular analysis results suggest that R. vitalii is circulating in the crab-eating fox population in Uruguay; however, its veterinary relevance for these foxes remains unknown.
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Canidae , Piroplasmida/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Animais , Feminino , Masculino , Prevalência , Infecções Protozoárias em Animais/parasitologia , Uruguai/epidemiologiaRESUMO
BACKGROUND: Despite the public health importance of toxocariasis/toxascariasis, only a few species of these ascaridoid parasites from wild canine and feline carnivores have been studied at the molecular level so far. Poor understanding of diversity, host distribution and the potential (zoonotic) transmission of the ascaridoid species among wild animals negatively affects their surveillance and control in natural settings. In this study, we updated previous knowledge by profiling the genetic diversity and phylogenetic relationships of ascaridoid species among eleven wild canine and feline animals on the basis of a combined analysis of the ribosomal internal transcribed spacer region (ITS) gene and the partial mitochondrial cytochrome c oxidase subunit 2 (cox2) and NADH dehydrogenase subunit 1 (nad1) genes. RESULTS: In total, three genetically distinct ascaridoid lineages were determined to be present among these wild carnivores sampled, including Toxocara canis in Alopex lagopus and Vulpes vulpes, Toxocara cati in Felis chaus, Prionailurus bengalensis and Catopuma temmincki and Toxascaris leonina in Canis lupus, Panthera tigris altaica, Panthera tigris amoyensis, Panthera tigris tigris, Panthera leo and Lynx lynx. Furthermore, it was evident that T. leonina lineage split into three well-supported subclades depending on their host species, i.e. wild felids, dogs and wolves and foxes, based on integrated genetic and phylogenetic evidence, supporting that a complex of T. leonina other than one species infecting these hosts. CONCLUSIONS: These results provide new molecular insights into classification, phylogenetic relationships and epidemiological importance of ascaridoids from wild canids and felids and also highlight the complex of the taxonomy and genetics of Toxascaris in their wild and domestic carnivorous hosts.
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Carnívoros/parasitologia , Toxascaris , Toxocara , Animais , Animais Selvagens/parasitologia , China , Classificação , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Helmintos , Helmintos/classificação , Helmintos/genética , Helmintos/isolamento & purificação , NADH Desidrogenase/genética , Filogenia , Toxascaris/classificação , Toxascaris/genética , Toxascaris/isolamento & purificação , Toxocara/classificação , Toxocara/genética , Toxocara/isolamento & purificaçãoRESUMO
Population-level surveys for Dirofilaria immitis in wild canids typically rely on identification of the parasite at necropsy. More recently, some studies have employed the use of the SNAP® 4Dx® Plus test. However, since the assay was designed for use with domestic dogs it needs to be validated for use with wild canids for accurate interpretation of results. We therefore evaluated the performance of the SNAP® 4Dx® Plus test for detection of D. immitis in wild canids in southern Ontario. Overall, 199 wild canid carcasses were collected from across the region and assessed for the presence of D. immitis parasites at necropsy; ten were infected. Lung tissue extract (LE) and thoracic fluid filter paper extract (TFE) prepared from each wild canid were tested via the SNAP® 4Dx® Plus test, which simultaneously tests for the presence of D. immitis antigen and antibodies to Borrelia burgdorferi, Anaplasma spp., and Ehrlichia spp. The prevalence adjusted bias adjusted kappa (PABAK) and Gwet's first-order-agreement coefficient (AC1) were used to assess the level of agreement between sample pairs. The PABAK and AC1 between LF and TFE applied to the SNAP® 4Dx® Plus test and the necropsy-confirmed D. immitis status indicated a very high level of agreement for all sample pairs. Compared to necropsy-confirmed D. immitis status, the estimated sensitivity and specificity of the SNAP® 4Dx® Plus test for D. immitis antigen in LE was 80 % (95 % CI 44.4-97.5%) and 98.9 % (95 % CI 96.2-99.9%), respectively. For the TFE, the sensitivity was 70 % (95 % CI 34.8-93.3%) and the specificity was 97.9 % (95 % CI 94.7-99.4%). With respect to the tick-borne pathogen components, 1.5 % (3/199; 95 % CI 0.3-4.5%) of wild canids tested positive for B. burgdorferi antibody; 1.0 % (2/199; 95 % CI 0-3.8%) of LE samples were positive and 0.5 % (1/199; 95 % CI 0-3.1%) of TFE samples were positive. No samples tested positive for antibody to Anaplasma spp. (95 % CI 0-2.3%) or Ehrlichia spp. (95 % CI 0-2.3%). Collectively, the results suggest that the SNAP® 4Dx® Plus test may be a suitable test for use with LE and TFE for the detection of D. immitis antigen in wild canids from southern Ontario.
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Antígenos de Helmintos/análise , Coiotes , Dirofilaria immitis/isolamento & purificação , Dirofilariose/epidemiologia , Raposas , Anaplasma/isolamento & purificação , Anaplasmose/epidemiologia , Anaplasmose/microbiologia , Animais , Anticorpos Antibacterianos/análise , Borrelia burgdorferi/isolamento & purificação , Testes Diagnósticos de Rotina/veterinária , Dirofilariose/parasitologia , Ehrlichia/isolamento & purificação , Ehrlichiose/epidemiologia , Ehrlichiose/microbiologia , Ehrlichiose/veterinária , Feminino , Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Doença de Lyme/veterinária , Masculino , Ontário/epidemiologia , Prevalência , Estudos SoroepidemiológicosRESUMO
Canids are a morphological and physiological diverse group of animals, with the most diversity found within one species, the domestic dog. Underlying observed morphological differences, there must also be differences at other levels of organization that could lead to elucidating aging rates and life span disparities between wild and domestic canids. Furthermore, small-breed dogs live significantly longer lives than large-breed dogs, while having higher mass-specific metabolic rates and faster growth rates. At the cellular level, a clear mechanism underlying whole animal traits has not been fully elucidated, although oxidative stress has been implicated as a potential culprit of the disparate life spans of domestic dogs. We used plasma and red blood cells from known aged domestic dogs and wild canids, and measured several oxidative stress variables: total antioxidant capacity (TAC), lipid damage, and enzymatic activities of catalase, superoxide dismutase, and glutathione peroxidase (GPx). We used phylogenetically informed general linear mixed models and nonphylogenetically corrected linear regression analysis. We found that lipid damage increases with age in domestic dogs, whereas TAC increases with age and TAC and GPx activity increases as a function of age/maximum life span in wild canids, which may partly explain longer potential life spans in wolves. As body mass increases, TAC and GPx activity increase in wild canids, but not domestic dogs, highlighting that artificial selection may have decreased antioxidant capacity in domestic dogs. We found that small-breed dogs have significantly higher circulating lipid damage compared with large-breed dogs, concomitant to their high mass-specific metabolism and higher growth rates, but in opposition to their long life spans.
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Peso Corporal/fisiologia , Longevidade/fisiologia , Estresse Oxidativo/fisiologia , Animais , Canidae , Catalase/sangue , Cães , Feminino , Glutationa Peroxidase/sangue , Masculino , Oxirredução , Filogenia , Superóxido Dismutase/sangueRESUMO
Safe and efficient techniques for the live capture of carnivores are limited. In this study, we identified some of the factors that could affect the success of capturing red fox cubs with live capture traps (also known as cage traps). During a three-year period, we analysed 32 captures of 25 fox cubs (1.3 captures/fox). We assessed the impact of the following factors: sex of animals, month of trapping, weather conditions recorded for each trap-night, the willingness of cubs to explore and enter cage traps, the researchers' activity around den complexes before trapping and distances to the nearest village or farm. The overall trap rate (32 captures, including recaptured cubs) and the trap rate for individual cubs (25 captures) was 11.2 cubs/100 trap-nights and 8.7/100 trap-nights, respectively. Animals other than foxes were captured only three times, thus the selectivity of the cage-trapping method was high (32/35 = 91.4%). The probability of capturing one cub per night was 70.2% (32 cubs/ 47 nights). Cubs inhabiting dens in the vicinity of human settlements were less likely to explore and enter traps. Vixens were more likely to relocate their litters if the activity of the staff setting the traps was intense at the trapping site. The success of trapping was higher during poor weather as, for example, during rain or thunderstorms. None of the trapped animals suffered any injuries. Whereas cage trapping can be an effective and safe capture method for juvenile foxes, capture efficiency is affected by the experience of the trappers and a range of other factors including weather and distance to human settlements.
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BACKGROUND: The conflict between predators and humans for resources such as game species or livestock is an ancient issue, and it is especially sharp in the case of medium-large wild canids. In order to manage this conflict, lethal control methods are often used, which can sometimes be illegal, such as poisoning. As an alternative, conditioned food aversion (CFA) is a non-lethal method to reduce predation in which animals learn to avoid a given food due to the adverse effects caused by the ingestion of an undetectable chemical compound added to this food. The present study aimed to test thiram as a CFA agent in penned dogs as a first approach to use this substance for reducing the predation conflict associated with wild canids. RESULTS: Thiram, with or without an additional odor cue, produced CFA in penned dogs for more than 2 months. Moreover, thiram seemed to be undetectable and safe after the third ingestion of a 40-60 mg kg-1 dose. Desirable adverse effects, such as vomits, appeared around 1 h after exposure. These characteristics make thiram optimal for its use in predation reduction through CFA. However, individual variability could prevent CFA acquisition by some animals. CONCLUSIONS: Thiram has the potential to be used as a CFA agent in wildlife management and conservation to reduce predation by wild canids. Since thiram produced CFA without the problems of detectability and toxicity caused by other substances, it may be an alternative to lethal control methods used to reduce predation on game, livestock and endangered species. © 2019 Society of Chemical Industry.
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Tiram , Animais , Animais Selvagens , Cães , Odorantes , Comportamento PredatórioRESUMO
Wild canids represent a potential reservoir host for Dirofilaria immitis infection in dogs in Ontario. Since wild canids are not protected by chemoprophylaxis, understanding the epidemiology of D. immmitis in these populations may help elucidate the background risk of infection for dogs. The aim of this study was to determine the prevalence and distribution of D. immitis infection in wild canids across southern Ontario. From February 2016 to March 2017, 290 wild canid carcasses (273 coyotes and 17 foxes) were collected from across the region and assessed for the presence of D. immitis at the time of necropsy. Overall, D. immitis infection was identified in 4.8% (95% CI 2.8-8.0%) of these wild canid carcasses. Among coyotes, 5.1% (95% CI 3.0-8.5%) were positive; no evidence of D. immitis was found in the 17 foxes. Dirofilaria immitis infections in wild canids were detected in two regions of southern Ontario: 12 of the 14 D. immitis infections were detected in the south-western region and two were detected in the eastern region. Our findings provide preliminary insights into the prevalence and geographical distribution of D. immitis in coyotes and foxes in southern Ontario.
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Coiotes , Dirofilaria immitis/isolamento & purificação , Dirofilariose/epidemiologia , Raposas , Animais , Dirofilariose/parasitologia , Feminino , Masculino , Ontário/epidemiologia , PrevalênciaRESUMO
Abstract A free-living, adult male maned wolf (Chrysocyon brachyurus) was referred to the Governador "Laudo Natel" - FCAV/Unesp veterinary hospital after being found with skin lesions and a fracture on the right pelvic limb, which had to be amputated due to compromised integrity. Around 20 days later, bilateral accentuated swollen on humerus-radius-ulna articulation was observed. The synovial liquid was drained and sent to the laboratory for synovial cytology with Rosenfeld staining that revealed predominantly degenerated neutrophils with karyolytic chromatin associated with intracellular inclusions suggestive of Hepatozoon sp. gametocytes. Blood and synovial liquid samples were submitted to molecular analysis, aiming to amplify the Hepatozoon spp. 18S rRNA gene fragment. Despite the positioning of the found Hepatozoon sequence together with Hepatozoon canis previously detected in domestic carnivores, the BLAST analysis showed only 98% identity with H. canis. To the best of the authors' knowledge, this is the first time a Hepatozoon was detected in the synovial liquid by clinical pathology and molecular analyses.
Resumo Um lobo guará (Chrysocyon brachyurus) adulto, macho, de vida livre foi encaminhado para atendimento no hospital veterinário Governador "Laudo Natel" - FCAV/Unesp após ser encontrado com lesões de pele e fratura em membro pélvico direito, sendo amputado devido a comprometimento da integridade do membro. Aproximadamente 20 dias após a chegada ao hospital, foi notado acentuado aumento de volume bilateral em região de articulação úmero-rádio-ulnar. O líquido sinovial foi drenado e enviado para análise citológica com coloração de Rosenfeld, revelando a presença de neutrófilos degenerados com cromatina cariolítica associados a inclusões intracelulares sugestivas de gametócitos de Hepatozoon sp. Amostras de sangue e líquido sinovial foram submetidas a análises moleculares visando amplificar um fragmento do gene 18S rRNA de Hepatozoon spp. Apesar da sequência de Hepatozoon detectada se posicionar filogeneticamente no mesmo clado que H. canis previamente detectado em carnívoros domésticos, o resultado da análise do BLAST mostrou somente 98% de identidade com H. canis. De acordo com o conhecimento dos autores, esta é a primeira vez que Hepatozoon foi detectado no líquido sinovial por meio de patologia clínica e análises moleculares.