Diversity and biogeographical patterns in the diet of the culpeo in South America.

Here we describe the dietary patterns of the culpeo or Andean fox (Lycalopex culpaeus) on a biogeographical scale. We also analyse the influence of exotic lagomorphs on its diet and explore differences between culpeo subspecies. We selected 17 mutually comparable diet studies, which include 19 independent diet assessments. Then, we extracted and standardized the values of the different diet components from these studies and calculated the relative frequency of occurrence of the 10 main trophic groups that we found. Further, we calculated the Shannon-Wiener H' trophic diversity index. The results showed that small mammals (41%), lagomorphs (21%), invertebrates (12.4%) and large herbivores (7.3%) were the most consumed groups. A factorial analysis of all trophic groups rendered four orthogonal factors that were used as response variables in relation to a set of environmental predictors. Altitude correlated with most factors (i.e. trophic groups). Exotic lagomorphs were consumed in lowlands, in higher latitudes and in regions showing high values of the human footprint index, enriching in those areas the culpeo's trophic spectrum. There were no differences in diet between the two main culpeo subspecies analysed, L.c. culpaeus and L.c. andinus. Finally, the best explanatory models (general linear model) of trophic diversity selected, using Akaike's information criterion, showed that the most diverse diets were those composed of large herbivores, edentates, carnivorous species, birds and herptiles (i.e. reptiles and frogs). Trophic diversity was low in rainy areas where big rodents dominated the diet. Neither latitude nor altitude seemed to have an effect on the trophic diversity of the culpeos, as they were not retained by the final models.

Molecular characterization of Sarcoptes scabiei causing severe mange in two Andean foxes (Lycalopex culpaeus) from Peru.

Cases of sarcoptic mange in the wildlife population have been increasing around the world in recent years. In this study, we report the first case of severe sarcoptic mange in two Andean foxes (Lycalopex culpaeus) and molecularly analyze the collected mites. The National Forestry and Wildlife Service of Lima, Peru, found an adult male Andean fox in the province of Callao in August 2022. The veterinarians decided to euthanize the fox due to the severity of the mange. In August 2023, an adult male Andean fox was found dead in the province of Huaral by veterinarians. Both foxes were sent to the veterinary school in Lima for necropsy. Skin samples from different body zones were digested in buffer lysis, and mites were detected in the tissue samples. A morphological diagnosis identified the mites as Sarcoptes scabiei. The mites from both foxes had the same nuclear (ITS2) and mitochondrial (cox1) genetic marker sequences as the S. scabiei sequences from dogs, vicunas, Andean foxes, and water buffalos recorded in GenBank. Unlike ITS2, phylogenetic analysis of S. scabiei cox1 showed host-related nucleotide sequence polymorphisms. Future molecular studies of S. scabiei from different hosts and localities will be necessary to better understand the transmission of this disease in Andean foxes.

Olfactory Enrichment in Hoary Foxes (Lycalopex vetulus LUND 1842): A Case Study.

We have tested a method of olfactory environmental enrichment in hoary foxes used in other wild canids in captivity. The individuals were exposed to four olfactory stimuli (meat, mouse urine, cheese, and egg) that were wrapped in cotton bags outside the enclosures at the zoo for five minutes. Behavioral observations were performed using the focal animal method, and all occurrences were recorded. The pre-exposure phase (Basal), exposure phase (Exp), and post-exposure phase and Basal phase (Pos) were analyzed for a period of five minutes. Behavioral responses were categorized as positive, negative, or other. Positive behavior tended to increase (p = 0.07) from the Basal phase to the Exp phase, but there was no statistical difference (p = 0.31) between the phases. Negative and other behavior did not differ statistically from the Basal phase to the Exp phase (N-, p = 0.32; Ot, p = 0.35) or Basal to the Pos phase (N-, p = 0.18; Ot, p = 0.92). The odors used seemed to elicit positive behavior weakly. Negative behavior was stable for the hoary foxes. The method failed to improve the hoary foxes' welfare. Because their natural diet is based on insects and fruits, it is suggested that the stimuli used in this study have no appetitive value for hoary foxes. The method used with the same olfactory stimuli that were successful in other canid species is unsuitable for hoary foxes.

Long-Tailed Pygmy Rice Rats Modify Their Behavioural Response and Faecal Corticosterone Metabolites in Response to Culpeo Fox but Not to Lesser Grison.

Even though behavioural and physiological reactions to predation risk exhibited by prey species have received considerable attention in scientific journals, there are still many questions still unsolved. Our aim was to broaden the knowledge on one specific question: do long-tailed pygmy rice rats adapt their behavioural and physiological antipredator strategies depending on the predator species? For this question, we live-trapped in a temperate forest in Southern Chile long-tailed pygmy rice rats (Oligoryzomys longicaudatus), which were exposed to three predator odour phases (Phase 0: preliminary, no predator cues; Phase 1: one plot with culpeo fox faeces (Lycalopex culpaeus), one plot with lesser grison (Galictis cuja) faeces and one plot acting as a control with no odour; Phase 2: post treatment, no predator cues). We measured the behavioural response by the capture ratio. To assess the physiological stress response, we collected fresh faecal samples to quantify faecal corticosterone metabolites (FCM). Our results showed that O. longicaudatus increased both the capture ratio and FCM levels in the presence of culpeo cues. Culpeo foxes have higher densities in the study area than G. cuja and exhibit a higher activity pattern overlap with O. longicaudatus. Moreover, it has been also been reported in other regions that L. culpaeus consumption of O. longicaudatus is more frequent compared to G. cuja diet. The increase in capturability could be because traps can be regarded as a shelter in high-risk settings, but it can also be explained by the predator inspection behaviour. The increase in FCM concentrations during culpeo treatment can be linked to the adaptive mobilisation of energy to execute antipredator responses to increase survival chances.

Livestock guarding dogs have minor effects on the parasite burden of wild carnivores.

Livestock guarding dogs are increasingly used to reduce carnivore-livestock conflicts, but no information is available to determine any adverse effects that these dogs may have on the health of wild carnivores. We assessed differences in prevalence, richness and severity of parasites in chilla fox (Lycalopex griseus) populations associated with livestock guarding dogs, which were routinely dewormed. We also evaluated whether the parasite assemblages of herding dogs, which were not dewormed, and chilla foxes were more similar in the presence of livestock guarding dogs. Scats of L. griseus and herding dogs were collected and screened for parasite eggs in areas with and without livestock guarding dogs to determine differences in prevalence, richness, intensity and parasite aggregation. We did not find any association between livestock guarding dogs and differences in parasite richness or prevalence of parasites. The intensity of parasites was higher among foxes positive to parasites when LGDs were present. A lower proportion of foxes with low parasite burdens occurred in areas with LGDs compared to areas without LGDs, but this difference was not significant at the population level. Our findings show the need to continue studying the effects of livestock guarding dogs on the health of wildlife with larger sample sizes and more locations.

An Hepatozoon americanum-like protozoan in crab-eating (Cerdocyon thous) and grey pampean (Lycalopex gymnocercus) foxes from Uruguay.

In South America, apicomplexan parasites of the genus Hepatozoon have been sporadically detected in mammals. Previous studies in wild canids from Brazil and Argentina demonstrated infections by species genetically related to Hepatozoon americanum. The aim of the present work was to detect the presence of Hepatozoon in road-killed foxes encountered in Uruguayan highways. Blood samples from 45 crab-eating (Cerdocyon thous) and 32 grey pampean (Lycalopex gymnocercus) foxes were analyzed by PCR for Hepatozoon 18S rRNA gene. Eight foxes (10.4%) were found to be infected with an H. americanum-like protozoan, an Hepatozoon closely related to H. americanum. Bayesian and maximum-likelihood phylogenetic analyses revealed that the sequences obtained in this study cluster with H. americanum from the United States, and with an H. americanum-like species from dog and foxes from Brazil and Argentina. In the Unites States, H. americanum causes severe disease in dogs. In addition to this, an increasing habitat overlap between dogs and foxes makes the presence of H. americanum-like protozoan in foxes acquires veterinary relevance. This work represents the first report of L. gymnocercus infected with an H. americanum-like protozoan, and of wild canids infected with Hepatozoon in Uruguay.

Survey of Zoonotic Bacterial Pathogens in Native Foxes in Central Chile: First Record of Brucella canis Exposure.

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.

Morphological and molecular evidence of Oslerus osleri (Nematoda: Filaroididae) in the Andean fox (Lycalopex culpaeus).

Oslerus osleri is a cosmopolitan filaroid nematode that parasitizes the respiratory system of domestic and wild canids. Natural infection by O. osleri is reported in the Andean fox (Lycalopex culpaeus) in this study. Nematodes, enclosed in small and compact fibrous nodules of 1 to 5 mm in diameter, were found on the surface of the trachea near the bronchial bifurcation on four Andean foxes during necropsy (one from Cuzco, Peru and three from Northwestern Patagonia in Argentina). The nematodes were identified as O. osleri by morphological and molecular methods. Ribosomal and mitochondrial DNA analyses were performed amplifying the second internal transcribed spacer region (ITS-2), the partial cytochrome c oxidase 1 (cox1), and the large subunit of nuclear ribosomal RNA (LSU rRNA) genes. Sequences of the ITS-2 and LSU rRNA had a genetic variation of 1.5% and 1.0%, respectively, with previous sequences of O. osleri registered in Genbank. This is the first amplification of the cox1 gene of O. osleri and demonstrated an identity of 92% to Perostrongylus falciformis (KY365437), and 90% to Angiostrongylus cantonensis (KY779735) and Angiostrongylus costaricensis (AP017675).

Wild and Domestic Canids and Their Interactions in the Transmission Cycles of Trypanosoma Cruzi and Leishmania spp. in an Area of the Brazilian Cerrado.

Trypanosoma cruzi and Leishmania spp. are parasites that infect multiple hosts including canids, considered bioaccumulators of parasites. Deforestation in the Cerrado biome has resulted in the exposure of wild canids to anthropized areas, where they may establish ecological and epidemiological relationships with domestic dogs. We evaluated the infection by trypanosomatids in canids from a Cerrado agroecosystem between 2013 and 2017. Samples of wild canids (blood, bone marrow and skin) and dogs (blood) were collected for parasitological, serological and molecular diagnosis. A total of 414 samples from wild (n = 131) and domestic (n = 283) canids were collected, including recaptures. We obtained five positive hemocultures from Lycalopex vetulus (n = 2), Cerdocyon thous (n = 1) and dogs (n = 2), all characterized as T. cruzi TcIII/V (18S rDNA) and TcIII/V/VI (gGAPDH); one positive skin fragment for Leishmania sp. (C. thous), one positive skin culture (Chrysocyon brachyurus) and one positive fresh blood examination from a dog. Infection by T. cruzi and Leishmania spp. was serologically confirmed in 18% and 4% of the canids, respectively. Active transmission was attested by seroconversion events and occurred despite the low rate of positive parasitological assays. Wild and domestic canids infected by both parasites were detected sharing the same areas, pointing to a possible spillover of parasites among them.

A forest-specialist carnivore in the middle of the desert?Comments on https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.5230.

We present comments on an article recently published in Ecology and Evolution ("High-resolution melting of the cytochrome B gene in fecal DNA: A powerful approach for fox species identification of the Lycalopex genus in Chile") by Anabalon et al. that reported the presence of Darwin's fox (Lycalopex fulvipes), a temperate forest specialist, in the hyperarid Atacama Desert of northern Chile. We argue that this putative record lacks ecological support in light of ongoing research on this endangered species, and contains numerous methodological flaws and omissions related to the molecular identification of the species. Based on these issues, we suggest the scientific community and conservation decision-makers disregard the alleged presence of the Darwin's fox in the Atacama Desert.

Hemoplasmas Are Endemic and Cause Asymptomatic Infection in the Endangered Darwin's Fox (Lycalopex fulvipes).

Mycoplasma haemocanis is prevalent in the endangered Darwin's fox (Lycalopex fulvipes) in its main stronghold, Chiloé Island (Chile). The origin of the infection, its dynamics, its presence in other fox populations and the potential consequences for fox health remain unexplored. For 8 years, hemoplasmal DNA was screened and characterized in blood from 82 foxes in Chiloé and two other fox populations and in 250 free-ranging dogs from Chiloé. The prevalence of M. haemocanis in foxes was constant during the study years, and coinfection with "Candidatus Mycoplasma haematoparvum" was confirmed in 30% of the foxes. Both hemoplasma species were detected in the two mainland fox populations and in Chiloé dogs. M. haemocanis was significantly more prevalent and more genetically diverse in foxes than in dogs. Two of the seven M. haemocanis haplotypes identified were shared between these species. Network analyses did not show genetic structure by species (foxes versus dogs), geographic (island versus mainland populations), or temporal (years of study) factors. The probability of infection with M. haemocanis increased with fox age but was not associated with sex, season, or degree of anthropization of individual fox habitats. Some foxes recaptured years apart were infected with the same haplotype in both events, and no hematological alterations were associated with hemoplasma infection, suggesting tolerance to the infection. Altogether, our results indicate that M. haemocanis is enzootic in the Darwin's fox and that intraspecific transmission is predominant. Nevertheless, such a prevalent pathogen in a threatened species represents a concern that must be considered in conservation actions.IMPORTANCEMycoplasma haemocanis is enzootic in Darwin's foxes. There is a higher M. haemocanis genetic diversity and prevalence in foxes than in sympatric dogs, although haplotypes are shared between the two carnivore species. There is an apparent tolerance of Darwin's foxes to Mycoplasma haemocanis.

Ocurrencia de Mesocestoides sp. (Cestoda: Mesocestoididae) en el zorro andino (Lycalopex culpaeus) / Occurrence of Mesocestoides sp. (Cestoda: Mesocestoididae) in the Andean fox (Lycalopex culpaeus)

Resumen En este trabajo, informamos Mesocestoides sp. parasitando a un individuo de Lycalopex culpaeus (zorro andino) procedente del Abra la Raya, departamento de Cusco, Perú. El individuo fue necropsiado en el Instituto Veterinario de Investigaciones Tropicales y de Altura (IVITA), sede de Maranganí. Numerosos cestodos se recolectaron del intestino delgado y se analizaron morfológicamente. Se proporciona una breve descripción morfológica de los especímenes de Mesocestoides, así como una discusión con respecto de especies anteriormente registradas para Perú.

Abstract In this work, we report Mesocestoides sp. parasiting one individual of Lycalopex culpaeus (Andean fox) captured from the Abra la Raya, Department of Cusco, Peru. The individual was necropsed in the Instituto Veterinario de Investigaciones Tropicales y de Altura (IVITA), Maranganí Headquarters. Numerous cestodes collected from the small intestine and morphologically analyzed. We provided a brief morphological description of Mesocestoides specimenes, and discuss concerning previous Mesocestoides species registered in Peru.

Wild carnivores, domestic dogs and ticks: shared parasitism in the Brazilian Cerrado.

The increase of contact between natural and rural areas is prominent in Brazil, due to agricultural activities and concern with the environmental conservation. In this context, domestic animals, wild fauna and humans are exposed to mutual exchange of parasites, microorganisms and diseases. We studied tick parasitism of wild carnivores and domestic dogs, and the environmental of questing ticks, in extensive cattle ranch areas intermingled with natural vegetation, and in a natural reserve, both in a region of Cerrado biome, Midwestern Brazil. From 2008 to 2015, we inspected 119 wild carnivores from nine species, and collected six tick species (Amblyomma sculptum, Amblyomma ovale, Amblyomma dubitatum, Amblyomma tigrinum, Dermacentor nitens and Rhipicephalus microplus). The most numerous and infested hosts were Cerdocyon thous, Lycalopex vetulus, Chrysocyon brachyurus, Puma concolor and Conepatus amazonicus. From 139 domestic dogs, we collected A. sculptum, Rhipicephalus sanguineus and R. microplus. From vegetation, samplings resulted in A. sculptum, A. dubitatum, A. ovale, Amblyomma rotundatum and R. microplus, with dominance of A. sculptum. Domestics and wild animals presented high overlapping of infestations by A. sculptum, a generalist and anthropophilic tick species. This tick is the most important vector of the Brazilian spotted fever, a lethal human disease. This fact elicits attention and requires efforts to monitor the presence of pathogens vectored by ticks circulating in this type of agroecosystem, including in other regions of the Brazil, because the most of the natural vegetation remaining have been increasingly immersed in pastures and agricultural matrix.

A putative novel strain of Ehrlichia infecting Amblyomma tigrinum associated with Pampas fox (Lycalopex gymnocercus) in Esteros del Iberá ecoregion, Argentina.

The current work evaluated road-killed Pampas foxes (Lycalopex gymnocercus) and their ticks for the presence of vector-borne agents in the ecoregion Esteros del Iberá in northeastern Argentina. Spleen, lung and blood samples and Amblyomma tigrinum adult ticks collected from the foxes were tested by polymerase chain reaction (PCR) assays targeting bacteria of the genera Ehrlichia, Anaplasma, and Rickettsia. All foxes tested were negative for the three genera, but evidence of Ehrlichia and Rickettsia infection was detected in the ticks. One A. tigrinum (out of 12 tested) was infected by an ehrlichial agent, here named Ehrlichia sp. strain Iberá, related to ehrlichial agents recently detected in platypuses in Tasmania (Ornithorhynchus anatinus) and in voles (Myodes rutilus and Myodes rufocanus) and shrews (Sorex araneus) in the Russian Far East. Regarding Rickettsia, all A. tigrinum ticks (100%) were infected by ´Candidatus Rickettsia andeanae´, a member of the spotted fever group rickettsia of unknown pathogenicity. Further research is necessary to unveil the ecology of Ehrlichia sp. strain Iberá as well as its zoonotic relevance. The species of the genus Ehrlichia are known to be pathogenic to mammals, including humans and domestic animals, thus the presence of this ehrlichial agent in A. tigrinum is a potential risk for veterinary and public health, as the adults of A. tigrinum are common parasites of dogs in rural and peri-urban environments, and humans are also frequently bitten by this tick species.

High-resolution melting of the cytochrome B gene in fecal DNA: A powerful approach for fox species identification of the Lycalopex genus in Chile.

Easy, economic, precise species authentication is currently necessary in many areas of research and diagnosis in molecular biology applied to conservation studies of endangered species. Here, we present a new method for the identification of three fox species of the Lycalopex genus in Chile. We developed an assay based on high-resolution melt analysis of the mitochondrial cytochrome B gene, allowing a simple, low cost, fast, and accurate species determination. To validate the assay applicability for noninvasive samples, we collected fecal samples in the Atacama Desert, finding unexpectedly one species outside of its known distribution range. We conclude that the assay has a potential to become a valuable tool for a standardized genetic monitoring of the Lycalopex species in Chile.

Morphometry of the mandibular foramen applied to local anesthesia in hoary fox (Lycalopex vetulus) / Morfometria do forame mandibular aplicada à anestesia local em raposa-do-campo (Lycalopex vetulus)

Great part of the veterinary care in wild carnivores is intended to treat the dental disorders, and oral cavity disorders may generally affect the animal health as a whole. It is factual that knowing the location of the mandibular foramen is vital for local anesthetic block of the inferior alveolar nerve, however, there is still no data on the morphometry of the hoary fox mandibular foramen. The aim was describing morphometry of the mandibular foramen of this species and associating its position with anatomic reference points in the mandible, thus providing support for more effective local anesthetic block of the inferior alveolar nerve in such species. Four adult jaws of Lycalopex vetulus were used. Radiography and biometrics of the hemimandibulas were performed. The rostral third of the jaw body in a lateral view presented three mental foramens, being a rostral, a medium and a caudal. Each hemimandibula presented I3/C1/PM4/M3. The angle of the mandible was marked by the masseteric fossa, the angular incisure, the angular process and the mandibular foramen, and this last one located perpendicularly to the dorsal edge of the angular incisures in medial view. In this view, the crevice to the milohyoid nerve, projected in the caudodorso rostral direction, was also evidenced. The ramus of the mandible was characterized by the presence of the condylar and coronoid processes, and by the dorsal and ventral mandibular incisions. Statistical analyzes did not present significant differences between the antimeres of the studied animals, and the penetration of the needle perpendicularly to the dorsal end of the angular incision on average 8.79mm, overlapped to the medial face of the angle of the mandible could be indicated. Alternatively, the access may also be achieved by inserting the needle in an average of 17.69mm perpendicular to the dorsal end of the angular process, in contact with the medial aspect of the angle of the mandible, and in caudo-rostral projection, also allowing a better anesthetic blockade of the inferior alveolar nerve in L. vetulus. It can also be concluded that the masseteric fossa, the dorsal and ventral mandibular angles, the crevice to the milohyoid nerve, the ramus of the mandible and the mandibular foramen presented differences in their topographic descriptions when compared to the other canids.(AU)

A maior parte dos atendimentos veterinários em carnívoros silvestres destina-se ao tratamento das afecções dentárias, sendo que doenças de cavidade oral podem afetar a saúde do animal como um todo. É factível que o conhecimento da localização do forame mandibular é essencial para o bloqueio anestésico local do nervo alveolar inferior, entretanto, ainda são inexistentes dados sobre a morfometria do forame mandibular de raposa-do-campo. Objetivou-se descrever a morfometria do forame mandibular desta espécie, e correlacionar sua posição com pontos de referência anatômica na mandíbula, oferecendo subsídio para um bloqueio anestésico local mais efetivo do nervo alveolar inferior nesta espécie. Foram utilizadas quatro mandíbulas de cadáveres adultos de Lycalopex vetulus. Realizou-se a radiografia e as biometrias das hemimandíbulas. O terço rostral do corpo da mandíbula em uma vista lateral apresentou três forames mentuais, sendo um rostral, um médio e um caudal. Cada hemimandíbula apresentou I3/C1/PM4/M3. O ângulo da mandíbula foi marcado pela fossa massetérica, pela incisura angular, pelo processo angular e pelo forame mandibular, e este último localizado perpendicularmente ao extremo dorsal da incisura angular em vista medial. Nesta vista, também se evidenciou o sulco para o nervo milohióideo, projetado em sentido caudodorsorostral. O ramo da mandíbula foi caracterizado pela presença dos processos condilar e coronóide, e pelas incisuras mandibulares dorsal e ventral. As análises estatísticas não apresentaram diferenças significantes entre os antímeros dos animais estudados, podendo-se indicar a penetração da agulha perpendicularmente ao extremo dorsal da incisura angular em média 8,79mm, justaposto à face medial do ângulo da mandíbula. Alternativamente, o acesso também poderá ser realizado introduzindo a agulha em média 17,69mm de forma perpendicular ao extremo dorsal do processo angular, em contato com a face medial do ângulo da mandíbula, e em projeção caudorostral, permitindo também um melhor bloqueio anestésico do nervo alveolar inferior na L. vetulus. Também se pode concluir que a fossa massetérica, as incisuras angular, mandibulares dorsal e ventral, o sulco para o nervo milohióideo, o ramo da mandíbula e o forame mandibular apresentaram diferenças em suas descrições topográficas quando comparados aos demais canídeos.(AU)

Detection of Rangelia vitalii (Piroplasmida: Babesiidae) in asymptomatic free-ranging wild canids from the Pampa biome, Brazil.

Canine rangeliosis is a tick-borne disease caused by the protozoan Rangelia vitalii, which has only been reported in South America. With this knowledge, we hypothesized that neotropical foxes could act as asymptomatic natural carriers of R. vitalii. To test this, we captured 44 free-ranging foxes and investigated the presence of R. vitalii DNA, and whether the infected animals presented any clinical findings or hematological changes. Eight foxes (18%), seven Cerdocyon thous (7/27-25%), and one Lycalopex gymnocercus (1/17-5%) were positive for R. vitalii. All foxes were clinically healthy and showed no hematological abnormalities. Thus, we propose that neotropical canids, particularly C. thous, could be the natural carriers of R. vitalii.

Morphological and molecular identification of Spirocerca lupi (Nematoda: Spiruridae) found in the Andean fox (Lycalopex culpaeus).

Lesions compatible with spirocercosis were found in the esophagus and aorta of an Andean fox from Cuzco, Peru. The esophageal and aortic lesions were 5.5 and 1.5 cm in diameter, respectively. A total of 12 adult nematodes (6 males and 6 females) were collected from the esophageal lesion, and all were identified as Spirocerca lupi by morphological and molecular methods. Molecular characterization was performed by analyzing two sources of the cox1 gene, and the sequences were compared with previous S. lupi sequences from other work deposited in GenBank. Analysis of the partial cox1 gene from S. lupi (n = 3) showed 2 haplotypes and had 95-99% nucleotide similarity to previously described sequences. Also, molecular analysis showed that S. lupi is a very diverse group, due to the genetic variability of the partial sequences of the cox1 gene of Spirocerca. This study is the first to report finding of spirocercosis in the Andean fox.

Ecological niche modeling re-examined: A case study with the Darwin's fox.

Many previous studies have attempted to assess ecological niche modeling performance using receiver operating characteristic (ROC) approaches, even though diverse problems with this metric have been pointed out in the literature. We explored different evaluation metrics based on independent testing data using the Darwin's Fox (Lycalopex fulvipes) as a detailed case in point. Six ecological niche models (ENMs; generalized linear models, boosted regression trees, Maxent, GARP, multivariable kernel density estimation, and NicheA) were explored and tested using six evaluation metrics (partial ROC, Akaike information criterion, omission rate, cumulative binomial probability), including two novel metrics to quantify model extrapolation versus interpolation (E-space index I) and extent of extrapolation versus Jaccard similarity (E-space index II). Different ENMs showed diverse and mixed performance, depending on the evaluation metric used. Because ENMs performed differently according to the evaluation metric employed, model selection should be based on the data available, assumptions necessary, and the particular research question. The typical ROC AUC evaluation approach should be discontinued when only presence data are available, and evaluations in environmental dimensions should be adopted as part of the toolkit of ENM researchers. Our results suggest that selecting Maxent ENM based solely on previous reports of its performance is a questionable practice. Instead, model comparisons, including diverse algorithms and parameterizations, should be the sine qua non for every study using ecological niche modeling. ENM evaluations should be developed using metrics that assess desired model characteristics instead of single measurement of fit between model and data. The metrics proposed herein that assess model performance in environmental space (i.e., E-space indices I and II) may complement current methods for ENM evaluation.

Hammondia sp. oocysts shed by a Brazilian fox (Lycalopex vetulus) differ from Hammondia heydorni and Hammondia triffittae.

A Brazilian fox (Lycalopex vetulus) was rescued from a highway, and 16 days after maintained in captivity, the fox shed oocysts with sizes compatible with Hammondia sp. and Neospora caninum. DNA extracted from oocysts were initially tested in two PCRs targeting the internal transcribed spacer 1 (ITS-1) of the rDNA of Hammondia heydorni and the Nc-5 gene of N. caninum. A 270-bp product was visualized in the PCR for H. heydorni. No amplification was observed for N. caninum PCR. Since ITS-1-based PCR is not sufficient to differentiate Hammondia species derived from canids, oocyst DNA was examined using multilocus sequence analysis of five genetic fragments [intron 1 of the alpha tubulin gene (intron 1), internal transcribed spaces 1 and 2 (ITS-1 and ITS-2) of the rDNA, 28S rRNA gene (D2/D3 domain), and heat shock protein 70 (Hsp70)]. The Hammondia sp. oocyst from the Brazilian fox, referred here as H-FOXBR isolate, is closely related to H. heydorni and Hammondia triffittae, but differs from these parasites in three genetic markers (alpha tubulin gene, ITS-2, and 28S rRNA). As reported by other research groups, Hammondia spp. excreted by canids are genetically diverse and may encompass additional species besides H. heydorni and H. triffittae. In this study, we confirmed that H-FOXBR has significant genetic differences in comparison to H. heydorni and H. triffittae and may represent a separate species. Further studies are needed to identify the life cycle of this parasite and to characterize the parasite stages in the intermediate and definitive hosts.