Description of the parasitic fauna of a specimen of Didelphis albiventris at Rio Grande do Sul.

Didelphis albiventris is considered the most common marsupial in Rio Grande do Sul. With omnivorous and synanthropic habits, it can serve as a host to various parasites, playing an important role in maintaining their biological cycle. Despite being a widespread and abundant species, it has a relatively little-known parasitic fauna. Therefore, the aim of this study was to report the diversity of parasites in a fecal sample from D. albiventris in Rio Grande do Sul, Southern Brazil. Modified Centrifugal-flotation and Spontaneous sedimentation techniques were used, revealing a high taxonomic diversity of parasites. Eggs of Ancylostoma spp., Toxocara spp., and Anoplocephalidae were reported for the first time in the host in the southern region of the country, along with the first report of pseudoparasitism by Syphacia spp. and Monocystis spp. in this animal species. The presence of different parasites in the feces of D. albiventris is of utmost importance, primarily for public health, but also for understanding the biodiversity of parasites present in wildlife, which has been poorly studied until now. This allows the implementation of effective strategies for controlling, preventing and treating these diseases.

Didelphis albiventris é considerado o marsupial mais comum no Rio Grande do Sul. Com hábitos onívoros e sinantrópicos, pode servir de hospedeiro para diversos parasitas, desempenhando importante papel na manutenção do seu ciclo biológico. Apesar de ser uma espécie difundida e abundante, possui uma fauna parasitária relativamente pouco conhecida. Portanto, o objetivo deste estudo foi relatar a diversidade de parasitas em uma amostra fecal de D. albiventris no Rio Grande do Sul, Sul do Brasil. Foram utilizadas técnicas modificadas de flutuação centrífuga e sedimentação espontânea, revelando uma alta diversidade taxonômica de parasitas. Ovos de Ancylostoma spp., Toxocara spp. e Anoplocephalidae foram relatados pela primeira vez no hospedeiro na região sul do país, juntamente com o primeiro relato de pseudoparasitismo por Syphacia spp. e Monocystis spp. nesta espécie animal. A presença de diferentes parasitas nas fezes de D. albiventris é de extrema importância, principalmente para a saúde pública, mas também para a compreensão da biodiversidade de parasitas presentes na vida selvagem, que tem sido pouco estudada até agora. Isto permite a implementação de estratégias eficazes para controlar, prevenir e tratar estas doenças.

Morphology and computed tomography of the larynx in the white-eared opossum (Didelphis albiventris).

The white-eared opossum (Didelphis albiventris) is a Neotropical marsupial that occurs in the Brazilian territory. The larynx is an important organ of vocalization in mammals, although, other laryngeal functions are more fundamental for survival of mammals than phonation. The anatomical knowledge of respiratory structures is pivotal for a better understanding of the species. Thus, this study aimed to examine the larynx of the white-eared opossum by gross anatomy, computed tomography and histological description. For this, 10 adult (six females and four males) white-eared opossums (D. albiventris) were used. The white-eared opossum larynx was formed by epiglottis, thyroid, cricoids and arytenoid cartilages and a corniculate process. There is a similarity between the larynx of this marsupial and those reported in other wild mammals, regarding the number of cartilages and their location. Histologically, the epiglottis consisted of elastic cartilage and thyroid, cricoid and arytenoid cartilages were composed of hyaline cartilage. The epiglottis protruded rostrally into the nasal part of the pharynx, above the soft palate, and this is probably a marsupial characteristic as the fact that the thyroid and cricoid cartilages were ventrally fused. The hyoid apparatus was similar to that of other animals, with the same bony constitution, but with a greatly reduced stylohyoid bone. Histologically, the larynx was similar to those of other species such as koala, armadillo, crab-eating foxes and giant anteaters. The knowledge of the larynx morphology is important for the anatomical features of the species and clinical and surgical procedures, such as endotracheal intubation.

Ctenocephalides felis (Siphonaptera, Pulicidae) parasitizing White-eared opossum (Didelphis albiventris) at Southern Brazil - Case report.

Didelphis albiventris is a marsupial with synanthropic habits, whose contact with domestic animals and humans is increasing. They are considered potential disseminators of diseases, present as definitive hosts or reservoirs of various pathogenic agents. The present study aim to report, for the first time, the parasitism by Ctenocephalides felis in D. albiventris in Rio Grande, Southern Rio Grande do Sul state, Brazil. An adult female White-eared Opossum (D. albiventris), killed by being run over, was collected on the roads of the city of Rio Grande, Rio Grande do Sul, Brazil and sent to the laboratory for necropsy. During external inspection, a flea was found, which was stored in 70o alcohol until taxonomic identification, being classified as C. felis. This study reports the occurrence of parasitism by C. felis in D. albiventris for the first time in the location studied, demonstrating that these arthropods circulate between the wild and urban environments, and play an important role in the cycle of zoonotic pathogens among wild fauna, companion animals and humans.

Didelphis albiventris é um marsupial de hábitos sinantrópicos, cujo contato com animais domésticos e humanos está aumentando. São considerados potenciais disseminadores de doenças, apresentando-se como hospedeiros definitivos ou reservatórios de vários agentes patogênicos. O presente estudo tem como objetivo relatar, pela primeira vez, o parasitismo por Ctenocephalides felis em D. albiventris em Rio Grande, Sul do Rio Grande do Sul, Brasil. Uma fêmea adulta de gambá-de-orelha-branca (D. albiventris), morta por atropelamento, foi recolhida nas estradas da cidade de Rio Grande, Rio Grande do Sul, Brasil e encaminhado ao laboratório para necropsia. Durante inspeção externa foi encontrada uma pulga que foi armazenada em álcool 70º até a identificação taxonômica sendo classificado como C. felis. Este estudo relata a ocorrência de parasitismo por C. felis em D. albiventris para o primeira vez no local estudado, demonstrando que esses artrópodes circulam entre a natureza e ambientes urbanos e desempenham um papel importante no ciclo de patógenos zoonóticos entre a fauna selvagem, animais de companhia e humanos.

Undifferentiated pleomorphic sarcoma in a white-eared opossum (Didelphisalbiventris).

We report a case of high-grade undifferentiated pleomorphic sarcoma in a free-living white-eared opossum (Didelphis albiventris) in Central Brazil. Grossly, it appeared as a soft yellow mass, approximately 8 cm in diameter, with an irregular, adherent and ulcerated surface, which extended from the proximal epiphysis of the femur to the proximal third of the tibia and fibula. The mass invaded the medullary cavity and had a necrotic centre. Multiple nodular metastases (0.5-1.5 cm) were present in the liver, lungs and spleen. Histologically, the neoplasm was characterized by pleomorphic cells with indistinct boundaries, many multinucleated cells, necrosis and tissue invasion. There was intense cytoplasmic immunolabelling of neoplastic cells for vimentin and moderate cytoplasmic and nuclear labelling for human muscle actin, human smooth muscle actin and lysozyme. Immunolabelling for Iba1, CD18, CD1A, cytokeratin AE1/AE3, glial fibrillary acidic protein and desmin was negative. To our knowledge, this is the first report of an undifferentiated pleomorphic sarcoma in this species.

Environmental enrichment techniques for black-eared-opossuns (Didelphis aurita Wied-Neuwied, 1826) in captivity / Técnicas de enriquecimento ambiental para gambás-de-orelha-preta (Didelphis aurita Wied-Neuwied, 1826) em cativeiro

Abstract This study aimed to analyze the efects of environmental dietary enrichment on the behavior of black-eared opossums that were in captivity at Centro de Triagem de Animais Silvestres (CETAS-ES), in the municipality of Serra-ES, from August to October 2022. Two food models were constructed for the study: the "Surprise Tubes" and the "Food Puzzle". A total of 24 juvenile black-eared opossums were selected, regardless of sex, and divided into eight groups, with three animals each. Then, four groups were exposed to one model and four to the other. Each group was submitted to two conditions: experimental, with the presence of the models, and control, without the presence of the models. Each condition lasted 24 hours and occurred on two consecutive days. They were flmed with a camera trap, resulting in 3,233 videos of 25 seconds. For the elaboration of the ethogram, 24 videos of each group were selected, recorded from 6:00 PM to 7:30 PM, when the animals were more active. The opossums interacted with both models, accessing, and eating the hidden food, preferring meat over fruit. No signifcant diferences were found in the behavior of opossums in relation to the models and it was observed that the aggressive behavior signifcantly decreased when the models were present. It is concluded that the models can be used as an environmental enrichment for black-eared-opossums, bringing benefts to the reduction of aggressive behavior.

Resumo O objetivo deste trabalho foi analisar os efeitos do enriquecimento ambiental alimentar no comportamento dos gambás-de-orelha-preta que se encontravam em cativeiro no Centro de Triagem de Animais Silvestres (CETAS), no município Serra, no estado do Espírito Santo (ES), de agosto a outubro de 2022. Dois modelos alimentares foram construídos para o estudo: os "Tubos Surpresa" e o "Quebra-Cabeça Alimentar". Foram selecionados 24 gambás-de-orelha-preta, independente do sexo, juvenis, divididos em oito grupos, com três animais cada, sendo quatro grupos expostos a um modelo e quatro ao outro. Cada grupo foi submetido a duas condições: experimental, com a presença do modelo e controle, sem a presença do modelo. Cada condição durou 24 horas e ocorreram em dois dias consecutivos. Foram filmadas com câmera trap, resultando em 3233 vídeos, de 25 segundos cada. Para elaboração do etograma foram selecionados 24 vídeos de cada grupo, gravados entre as 18h00 e 19h30hs, período em que os animais se mostraram mais ativos. Os gambás interagiram com os dois modelos, acessando e comendo os alimentos escondidos, havendo preferência pela carne em comparação com a fruta. Não houve diferença significativa no comportamento dos gambás em relação aos modelos e observou-se que o comportamento agressivo diminuiu significativamente quando os modelos estavam presentes. Conclui-se que os modelos podem ser utilizados como enriquecimento ambiental para os gambás-de-orelha-preta, trazendo benefícios para a diminuição do comportamento agressivo.

Hemoparasites in Didelphis aurita from Seropédica, Rio de Janeiro state, Brazil / Hemoparasitos em Didelphis aurita capturados em Seropédica, estado do Rio de Janeiro, Brasi

The present study aimed to use polymerase chain reaction (PCR) to detect species of the order Piroplasmida, such as Anaplasma spp., Borrelia spp., and Ehrlichia spp., circulating in the blood of Didelphis aurita in a peridomiciliary environment. Blood samples collected from big-eared opossum (Didelphis aurita) were screened for hemoparasites using PCR. The extracted DNA was tested for tick-borne hemoparasites. We were unable to detect hemoparasites, such as Ehrlichia spp., Babesia spp., Anaplasma spp., and Borrelia spp. Theileria DNA was detected in only one sample screened using PCR for an approximately 650-base pair fragment of the 18S rRNA gene. Sequencing and BLAST analysis of a subset of the PCR amplicons revealed 97% (535/553 bp) identity with Theileria bicornis. The detection of Theileria sp. in D. aurita challenges us to pursue more in-depth studies of marsupial piroplasmosids and to evaluate the morphological aspects of the findings and their possible involvement in zoonoses.

O objetivo do presente estudo foi utilizar a reação em cadeia da polimerase (PCR) para detectar espécies da ordem Piroplasmida, como Anaplasma spp., Borrelia spp. e Ehrlichia spp., circulando no sangue de Didelphis aurita em ambiente peridomiciliar. Amostras de sangue coletadas de gambá da orelha preta (Didelphis aurita) foram triadas para hemoparasitas por meio da PCR. O DNA extraído foi testado para alguns hemoparasitas transmitidos por carrapatos. Não conseguimos detectar hemoparasitos, como Ehrlichia spp., Babesia spp., Anaplasma spp. e Borrelia spp. O DNA de Theileria foi detectado apenas em uma amostra. Um fragmento de ~650 pares de bases do gene 18S rRNA foi sequenciado. e a análise pelo BLAST (um subconjunto de amplicons de PCR) revelou uma identidade de 97% (535/553 pb) com Theileria bicornis. A detecção de Theileria sp. in D. aurita nos desafia a aprofundar estudos sobre piroplasmosídeos marsupiais e avaliar os aspectos morfológicos dos achados e seu possível envolvimento com zoonoses.

Communal nesting is the optimal strategy for heat conservation in a social marsupial: lessons from biophysical models.

Endothermy, understood as the maintenance of continuous and high body temperatures owing to the combination of metabolic heat production and an insulative cover, is severely challenged in small endotherms inhabiting cold environments. As a response, social clustering combined with nest use (=communal nesting) is a common strategy for heat conservation. To quantify the actual amount of energy that is saved by this strategy, we studied the social marsupial Dromiciops gliroides (monito del monte), an endemic species of the cold forests of southern South America. It is hypothesized that sociability in this marsupial was driven by cold conditions, but evidence supporting this hypothesis is unclear. Here, we used taxidermic models ('mannequins') to experimentally test the energetic benefits of clustering combined with nest use. To do this, we fitted and compared cooling curves of solitary and grouped mannequins, within and outside of a nest, at the typical winter ambient temperatures of their habitat (5°C). We found that the strategy that minimized euthermic cost of maintenance was the combination of nest use and clustering, thus supporting communal nesting as a social adaptation to cope with the cold. Considering the basal metabolic rate of monitos, our estimates suggest that the savings represents almost half of energy consumption per day (in resting conditions). This study shows how simple biophysical models could help to evaluate bioenergetic hypotheses for social behavior in cold-adapted endotherms.

'Candidatus Mycoplasma Haemoalbiventris' and Tick-Borne Pathogens in Black-Eared Opossum (Didelphis aurita) from Southeastern Brazil.

The black-eared opossum (Didelphis aurita) is a South American synanthropic marsupial. The presence of opossums in domestic spaces is relevant in the One-Health context since they are hosts of pathogens and ectoparasites that may affect the health of domestic animals and humans. In this study, we aim to determine the occurrence of hemoplasmas and selected tick-borne pathogens in free-ranging black-eared opossums, along with their molecular characterization, hematological and biochemical evaluation and factors associated with infection, in the municipality of Viçosa, State of Minas Gerais, southeastern Brazil. Thirty black-eared opossums were trapped between March 2021 and June 2022. Ectoparasites were collected. Hematological and biochemical analyses were performed. DNA from EDTA-blood samples were analyzed by PCR and qPCR assays. By molecular analyses, 'Candidatus Mycoplasma haemoalbiventris' was the most prevalent hemoparasite (73.3%), followed by Hepatozoon sp. (22.2%). Significant differences were observed in the number of platelets, and in the concentration of protein and globulins in the animals infected by 'Ca. M. haemoalbiventris' when compared with the negative group. This is the first report of 'Ca. M. haemoalbiventris' infection in D. aurita.

Breeding and reproductive behaviour of the neo-tropical opossum, Didelphis marsupialis insularis, Allen 1902 under captive conditions / Reprodução e comportamento reprodutivo do gambá neotropical, Didelphis marsupialis insularis, Allen 1902, em condições de cativeiro

Developing a captive breeding system for the widely hunted Caribbean species of opossum Didelphis marsupialis insularis can greatly aide in the management and conservation of this species in the neo-tropics. Although this species possesses ideal traits for captive breeding in this region (tolerance to high heat and humidity, high reproductive rate, and resistance to disease), challenges due to its aggressive behaviour and limited information on its breeding behaviour have prevented a system from being developed for this species. The present study describes a breeding system, and the reproductive behaviour of this species under captive conditions. Six (1 male; 5 females) adult opossums were maintained and managed for breeding over a ten (10) month period. Pouch litter sizes averaged 5±2.5 with a range of 2 to 8. Gestation length was found to be 13.25±0.96 days and 4 litters (n=23) were successfully weaned at 11-13 weeks. It was found that the male D. m. insularis exhibits behaviours of interest that can serve as indicators for receptivity of the female, and overall, that this species can be successfully reared and bred under captive conditions in the neo-tropics.(AU)

O desenvolvimento de um sistema de criação em cativeiro para as espécies de gambá do Caribe amplamente caçadas, Didelphis marsupialis insularis, pode auxiliar bastante no manejo e conservação dessa espécie nos neotrópicos. Embora essa espécie possua características ideais para a criação em cativeiro nessa região (tolerância a altas temperaturas e umidade, alta taxa de reprodução e resistência a doenças), alguns fatores, como o seu comportamento agressivo e informações limitadas sobre seu comportamento reprodutivo, impediram o desenvolvimento de um sistema para D. m. insularis. O presente estudo descreve um sistema de criação e o comportamento reprodutivo dessa espécie em condições de cativeiro. Seis gambás adultos (1 macho e 5 fêmeas) foram mantidos para reprodução durante um período de 10 meses. O tamanho da ninhada em bolsa foi em média de 5 ± 2,5 com um intervalo de 2 a 8. A duração da gestação foi de 13,25 ± 0,96 dias, e 4 ninhadas (n = 23) foram desmamadas com sucesso de 11 a 13 semanas. Verificou-se que o macho D. m. insularis exibe comportamentos de interesse que podem servir como indicadores de receptividade da fêmea, e, em geral, essa espécie pode ser criada com sucesso em condições de cativeiro nos neotrópicos.(AU)

Thoracic evaluation and cardiac measurement using radiography in opossums (Didelphis albiventris) / Avaliação radiográfica de toráx e mensuração cardíaca de gambás (Didelphis albiventris)

Cardiac measurement by chest X-ray is very important in the cardiac characterization of dogs and cats, however, the wild animal clinic has a different reality. Opossums (Didelphis albiventris) are part of the Brazilian fauna and are frequently referred for clinical and radiographic evaluation. The objective of this research was to evaluate the thorax of skunks and establish the average of VHS and VLAS for these animals. Chest radiographs were performed in lateral and ventrodorsal projections to measure the VHS and VLAS, thoracic depth and tracheal diameter. The mean VHS was 7.85 (± 0.3) for males and 8.12 (± 0.5) for females and the measured VLAS was 1.19 (± 0.2) for both sexes. The mean value for thoracic depth was 1.13 (± 0.03) and the ratio between the diameter of the chest inlet and the diameter of the trachea was 0.25 (± 0.02), with no significant differences between the sexes. This is the first study that addresses the thoracic evaluation by tracheal and cardiac measurements of skunks through radiographic examination.(AU)

A mensuração cardíaca por meio de radiografia de tórax é muito importante na caracterização cardíaca de cães e gatos, porém, a clínica de animais silvestres tem uma realidade diferente. Os gambás (Didelphis albiventris) fazem parte da fauna brasileira e são frequentemente encaminhados para avaliação clínica e para avaliação radiográfica. O objetivo desta pesquisa foi avaliar o tórax de gambás e estabelecer a média de VHS e VLAS para esses animais. Foram realizadas radiografias de tórax em projeções laterais e ventro dorsais, para mensuração do VHS e VLAS, a profundidade torácica e o diâmetro traqueal. O VHS médio foi de 7,85 (± 0,3) para os machos e 8,12 (± 0,5) para as fêmeas e o VLAS mensurado foi de 1,19 (± 0,2) para ambos os sexos. O valor médio da profundidade torácica foi 1,13 (± 0,03) e a relação entre o diâmetro da entrada do tórax e o diâmetro da traqueia foi de 0,25 (± 0,02), sem diferenças significativas entre os sexos. Este é o primeiro estudo que aborda a avaliação torácica a medida traqueal e cardíaca de gambás por meio de exame radiográfico.(AU)

Small mammals and microhabitat selection in forest fragments in the transition zone between Atlantic Forest and Pampa biome

Natural resources are depleted in fragmented landscapes that have their vegetation also altered. As a result, the microhabitat diversity and the composition and distribution of local species are affected. In this study, we evaluated the small mammals' community diversity, composition and microhabitat selection in two Atlantic Forest fragments, in an ecotone area with the Pampa biome, southern Brazil. We recorded five rodents (Akodon montensis, Oligoryzomys nigripes, Sooretamys angouya, Juliomys pictipes and the exotic Rattus rattus) and one marsupial (Didelphis albiventris). Both fragments were dominated by the generalist rodent A. montensis. Akodon montensis and O. nigripes showed similar habitat preferences: ground covered by rocks and higher values of vegetation obstruction. Sooretamys angouya preferred places with higher abundance of trees. Fruit availability was important for A. montensis and D. albiventris, highlighting the importance of this food resource for local wildlife, and the potential role of these species as seed predators and dispersers. Small species richness, the presence of an exotic species and high dominance level suggest that the study area is highly degraded.(AU)

Breeding and reproductive behaviour of the neo-tropical opossum, Didelphis marsupialis insularis, Allen 1902 under captive conditions / Reprodução e comportamento reprodutivo do gambá neotropical, Didelphis marsupialis insularis, Allen 1902, em condições de cativeiro

Developing a captive breeding system for the widely hunted Caribbean species of opossum Didelphis marsupialis insularis can greatly aide in the management and conservation of this species in the neo-tropics. Although this species possesses ideal traits for captive breeding in this region (tolerance to high heat and humidity, high reproductive rate, and resistance to disease), challenges due to its aggressive behaviour and limited information on its breeding behaviour have prevented a system from being developed for this species. The present study describes a breeding system, and the reproductive behaviour of this species under captive conditions. Six (1 male; 5 females) adult opossums were maintained and managed for breeding over a ten (10) month period. Pouch litter sizes averaged 5±2.5 with a range of 2 to 8. Gestation length was found to be 13.25±0.96 days and 4 litters (n=23) were successfully weaned at 11-13 weeks. It was found that the male D. m. insularis exhibits behaviours of interest that can serve as indicators for receptivity of the female, and overall, that this species can be successfully reared and bred under captive conditions in the neo-tropics.

O desenvolvimento de um sistema de criação em cativeiro para as espécies de gambá do Caribe amplamente caçadas, Didelphis marsupialis insularis, pode auxiliar bastante no manejo e conservação dessa espécie nos neotrópicos. Embora essa espécie possua características ideais para a criação em cativeiro nessa região (tolerância a altas temperaturas e umidade, alta taxa de reprodução e resistência a doenças), alguns fatores, como o seu comportamento agressivo e informações limitadas sobre seu comportamento reprodutivo, impediram o desenvolvimento de um sistema para D. m. insularis. O presente estudo descreve um sistema de criação e o comportamento reprodutivo dessa espécie em condições de cativeiro. Seis gambás adultos (1 macho e 5 fêmeas) foram mantidos para reprodução durante um período de 10 meses. O tamanho da ninhada em bolsa foi em média de 5 ± 2,5 com um intervalo de 2 a 8. A duração da gestação foi de 13,25 ± 0,96 dias, e 4 ninhadas (n = 23) foram desmamadas com sucesso de 11 a 13 semanas. Verificou-se que o macho D. m. insularis exibe comportamentos de interesse que podem servir como indicadores de receptividade da fêmea, e, em geral, essa espécie pode ser criada com sucesso em condições de cativeiro nos neotrópicos.

Breeding and reproductive behaviour of the neo-tropical opossum, Didelphis marsupialis insularis, Allen 1902 under captive conditions

Abstract Developing a captive breeding system for the widely hunted Caribbean species of opossum Didelphis marsupialis insularis can greatly aide in the management and conservation of this species in the neo-tropics. Although this species possesses ideal traits for captive breeding in this region (tolerance to high heat and humidity, high reproductive rate, and resistance to disease), challenges due to its aggressive behaviour and limited information on its breeding behaviour have prevented a system from being developed for this species. The present study describes a breeding system, and the reproductive behaviour of this species under captive conditions. Six (1 male; 5 females) adult opossums were maintained and managed for breeding over a ten (10) month period. Pouch litter sizes averaged 5±2.5 with a range of 2 to 8. Gestation length was found to be 13.25±0.96 days and 4 litters (n=23) were successfully weaned at 11-13 weeks. It was found that the male D. m. insularis exhibits behaviours of interest that can serve as indicators for receptivity of the female, and overall, that this species can be successfully reared and bred under captive conditions in the neo-tropics.

Resumo O desenvolvimento de um sistema de criação em cativeiro para as espécies de gambá do Caribe amplamente caçadas, Didelphis marsupialis insularis, pode auxiliar bastante no manejo e conservação dessa espécie nos neotrópicos. Embora essa espécie possua características ideais para a criação em cativeiro nessa região (tolerância a altas temperaturas e umidade, alta taxa de reprodução e resistência a doenças), alguns fatores, como o seu comportamento agressivo e informações limitadas sobre seu comportamento reprodutivo, impediram o desenvolvimento de um sistema para D. m. insularis. O presente estudo descreve um sistema de criação e o comportamento reprodutivo dessa espécie em condições de cativeiro. Seis gambás adultos (1 macho e 5 fêmeas) foram mantidos para reprodução durante um período de 10 meses. O tamanho da ninhada em bolsa foi em média de 5 ± 2,5 com um intervalo de 2 a 8. A duração da gestação foi de 13,25 ± 0,96 dias, e 4 ninhadas (n = 23) foram desmamadas com sucesso de 11 a 13 semanas. Verificou-se que o macho D. m. insularis exibe comportamentos de interesse que podem servir como indicadores de receptividade da fêmea, e, em geral, essa espécie pode ser criada com sucesso em condições de cativeiro nos neotrópicos.

Breeding and reproductive behaviour of the neo-tropical opossum, Didelphis marsupialis insularis, Allen 1902 under captive conditions / Reprodução e comportamento reprodutivo do gambá neotropical, Didelphis marsupialis insularis, Allen 1902, em condições de cativeiro

Developing a captive breeding system for the widely hunted Caribbean species of opossum Didelphis marsupialis insularis can greatly aide in the management and conservation of this species in the neo-tropics. Although this species possesses ideal traits for captive breeding in this region (tolerance to high heat and humidity, high reproductive rate, and resistance to disease), challenges due to its aggressive behaviour and limited information on its breeding behaviour have prevented a system from being developed for this species. The present study describes a breeding system, and the reproductive behaviour of this species under captive conditions. Six (1 male; 5 females) adult opossums were maintained and managed for breeding over a ten (10) month period. Pouch litter sizes averaged 5±2.5 with a range of 2 to 8. Gestation length was found to be 13.25±0.96 days and 4 litters (n=23) were successfully weaned at 11-13 weeks. It was found that the male D. m. insularis exhibits behaviours of interest that can serve as indicators for receptivity of the female, and overall, that this species can be successfully reared and bred under captive conditions in the neo-tropics.

O desenvolvimento de um sistema de criação em cativeiro para as espécies de gambá do Caribe amplamente caçadas, Didelphis marsupialis insularis, pode auxiliar bastante no manejo e conservação dessa espécie nos neotrópicos. Embora essa espécie possua características ideais para a criação em cativeiro nessa região (tolerância a altas temperaturas e umidade, alta taxa de reprodução e resistência a doenças), alguns fatores, como o seu comportamento agressivo e informações limitadas sobre seu comportamento reprodutivo, impediram o desenvolvimento de um sistema para D. m. insularis. O presente estudo descreve um sistema de criação e o comportamento reprodutivo dessa espécie em condições de cativeiro. Seis gambás adultos (1 macho e 5 fêmeas) foram mantidos para reprodução durante um período de 10 meses. O tamanho da ninhada em bolsa foi em média de 5 ± 2,5 com um intervalo de 2 a 8. A duração da gestação foi de 13,25 ± 0,96 dias, e 4 ninhadas (n = 23) foram desmamadas com sucesso de 11 a 13 semanas. Verificou-se que o macho D. m. insularis exibe comportamentos de interesse que podem servir como indicadores de receptividade da fêmea, e, em geral, essa espécie pode ser criada com sucesso em condições de cativeiro nos neotrópicos.

Clinical, surgical, and radiographic aspects in a white-eared opossum (Didelphis albiventris) with traumatic diaphragmatic hernia / Aspectos clínicos, cirúrgicos e radiográficos em um Gambá-de-orelha-branca (Didelphis albiventris) com hérnia diafragmática traumática

This is the case of a specimen of Didelphis albiventris with signs of respiratory difficulty after a dog attack. Thoracic radiographic examination revealed pneumothorax, pulmonary contusion, and rib fracture, but no alteration compatible with diaphragmatic hernia was observed. Pneumothorax was reduced and the other alterations were treated. However, clinical manifestations persisted, and thus a contrast-gastrointestinal radiographic study was performed, showing abdominal organs in the thoracic cavity and loss of diaphragmatic line. The surgical approach was instituted, with access to the diaphragm through median laparotomy. Through the diaphragmatic rupture, present in the left antimere, there were herniated liver and gastric portions, intestinal segments, and omentum. After inspection and repositioning of the abdominal organs, the diaphragm raffia was performed with single sutures interrupted with 3-0 Nylon thread. The patients complete recovery occurred 14 days after the surgical procedure, with remission of clinical manifestations and normality of thoracic images in radiographic studies.(AU)

Esse é o caso de um espécime de Didelphis albiventris com sinais de dificuldade respiratória após ataque por cão. O exame radiográfico torácico revelou pneumotórax, contusão pulmonar e fratura de costelas, porém nenhuma alteração com-patível com hérnia diafragmática foi observada. O pneumotórax foi reduzido e as demais alterações tratadas. Contudo; houve a persistência das manifestações clínicas, e dessa forma um estudo radiográfico gastrointestinal contrastado foi realizado, sendo evidenciados órgãos abdominais na cavidade torácica e perda da linha diafragmática. A abordagem cirúrgica foi instituída, com acesso ao diafragma por meio de laparotomia mediana. Através da ruptura diafragmática, presente no antímero esquerdo, estavam herniadas porções hepáticas e gástricas, segmentos intestinais e omento. Após inspeção e reposicionamento dos órgãos abdominais, a rafia do diafragma foi realizada com suturas simples interrompidas com fio Nylon 3-0. A recuperação completa do paciente ocorreu 14 dias após o procedimento cirúrgico, com remissão das manifestações clínicas e normalidade das ima-gens torácicas nos estudos radiográficos.(AU)

Clinical, surgical, and radiographic aspects in a white-eared opossum (Didelphis albiventris) with traumatic diaphragmatic hernia / Aspectos clínicos, cirúrgicos e radiográficos em um Gambá-de-orelha-branca (Didelphis albiventris) com hérnia diafragmática traumática

This is the case of a specimen of Didelphis albiventris with signs of respiratory difficulty after a dog attack. Thoracic radiographic examination revealed pneumothorax, pulmonary contusion, and rib fracture, but no alteration compatible with diaphragmatic hernia was observed. Pneumothorax was reduced and the other alterations were treated. However, clinical manifestations persisted, and thus a contrast-gastrointestinal radiographic study was performed, showing abdominal organs in the thoracic cavity and loss of diaphragmatic line. The surgical approach was instituted, with access to the diaphragm through median laparotomy. Through the diaphragmatic rupture, present in the left antimere, there were herniated liver and gastric portions, intestinal segments, and omentum. After inspection and repositioning of the abdominal organs, the diaphragm raffia was performed with single sutures interrupted with 3-0 Nylon thread. The patient’s complete recovery occurred 14 days after the surgical procedure, with remission of clinical manifestations and normality of thoracic images in radiographic studies.

Esse é o caso de um espécime de Didelphis albiventris com sinais de dificuldade respiratória após ataque por cão. O exame radiográfico torácico revelou pneumotórax, contusão pulmonar e fratura de costelas, porém nenhuma alteração com-patível com hérnia diafragmática foi observada. O pneumotórax foi reduzido e as demais alterações tratadas. Contudo; houve a persistência das manifestações clínicas, e dessa forma um estudo radiográfico gastrointestinal contrastado foi realizado, sendo evidenciados órgãos abdominais na cavidade torácica e perda da linha diafragmática. A abordagem cirúrgica foi instituída, com acesso ao diafragma por meio de laparotomia mediana. Através da ruptura diafragmática, presente no antímero esquerdo, estavam herniadas porções hepáticas e gástricas, segmentos intestinais e omento. Após inspeção e reposicionamento dos órgãos abdominais, a rafia do diafragma foi realizada com suturas simples interrompidas com fio Nylon 3-0. A recuperação completa do paciente ocorreu 14 dias após o procedimento cirúrgico, com remissão das manifestações clínicas e normalidade das ima-gens torácicas nos estudos radiográficos.

Musculoskeletal anatomy and nomenclature of the mammalian epipubic bones.

Despite the well-established anatomy nomenclature for the marsupial skeleton, there are no names for the epipubic bone structures. Epipubic bones are paired bones articulating with the pubis and projecting cranially in the ventral body wall, present on the pelvic girdle of cynodonts, monotremes and marsupials. These bones were commonly thought to be related to pouch support in marsupials and more recently associated with locomotion. The parts of the epipubic bones have not been named and this has impeded proper morphological analysis. We analyzed the epipubic bones of 302 skeletons comprising American and Australian marsupials, as well as 27 monotreme skeletons, and dissected 10 marsupials for myological attachments analysis. We suggest the following nomenclature for the epipubic bone structures: crest for the cranial end, shaft for the body of the bone, lateral tubercle and the medial articular process. Some markings on the epipubic bone include the oblique line, pertaining to the attachment of external abdominal oblique muscle from the opposite side. The pyramidalis line is the suggested nomenclature for the pyramidalis muscle attachment and the inguinal ligament line for the inguinal ligament attachment. Regarding myology and attachments, based on dissections and review of the literature, the muscles pyramidalis, pectineus, external and internal abdominal oblique, transversus abdominis and rectus abdominis and the structures linea alba, linea semilunaris and the inguinal ligament are connected to the epipubic bone. As has been previously noted, anatomically, epipubic bones are so named due to their position (epi-above, pubic-pubis), and the same applies to structures such as the "epipubic process" or "epipubic cartilage" in amphibians and reptiles. While testing epipubic bone homology in vertebrates is beyond the scope of this work, we believe that using "epipubic bones" or epipubic cartilage/process as standardized terms for the structures found in the most cranial part of the superior ramus of the pubis would facilitate better anatomical communication. This should be valid for other similar terms, such as "epipubes" or "prepubis", that might occur in the literature in relation to this same physiographic position, and it should also be named as epipubic. We believe that this nomenclature will help in future morphologic studies.

Molecular Phylogeny of Cryptonanus (Didelphidae: Thylamyini): Evidence for a recent and complex diversification in South American open biomes.

Systematic revisions of South American marsupials have contributed to our knowledge about genus and species diversity in the last decades, including studies of the most recently described genus Cryptonanus (Didelphidae), currently comprising four recognized species. Herein we provide the first phylogeny for these mouse opossums based on comprehensive sampling, including representatives from all nominal taxa, encompassing most of the geographic distribution of the genus while also extending its known range. The taxonomic status of Cryptonanus species was explored by analyses of multiple mitochondrial and nuclear DNA markers to assess phylogenetic relationships and to provide divergence time estimates, species delimitations and biogeographical hypotheses. Cryptonanus monophyly remained highly supported despite the inclusion of abundant new data from more than a hundred specimens, comprising 10 independent evolutionary lineages. Species-complexes within valid nominal taxa reveal higher species richness in the genus. Based on divergence estimates from a dated phylogeny, we suggest that Cryptonanus diversified along the Quaternary, with speciation events occurring well into the Pleistocene. The best supported biogeographical hypothesis endorses speciation by vicariance and subset speciation across open formations in shaping the evolutionary history of this didelphid genus, strongly associated with dry tropical landscapes of South America.

Giardia and Cryptosporidium in Neo-Tropical Rodents and Marsupials: Is There Any Zoonotic Potential?

Cryptosporidiosis and giardiasis have been identified as emerging diseases in both developed and developing countries. Wildlife has been highlighted to play a major role in the spread of these diseases to humans. This review aims to highlight the research findings that relate to Cryptosporidium spp. and Giardia spp., with a focus on (1) parasitism of neo-tropical hystricomorphic rodents and marsupials from the genus Didelphis and (2) prevention and treatment strategies for humans and animals for the neo-tropical region. It was found that there are few studies conducted on neo-tropical rodent and marsupial species, but studies that were found illustrated the potential role these animals may play as zoonotic carriers of these two parasites for the neo-tropical region. Thus, it is recommended that further studies be done to assess the threat of protozoan parasites in neo-tropical wildlife to humans and domestic animals, and to further determine the most effective prophylaxis adapted for the unique conditions of the region.

Anatomical characteristics of the bones of the thoracic limb of white-eared opossum (Didelphis albiventris) / Características anatómicas de los huesos del miembro torácico de la zarigüeya oreja blanca (Didelphis albiventris)

SUMMARY: The skeleton of the thoracic limb is one of the key aspects for the understanding of the habits and movement of different mammalian species. Considering the gap about studies related to marsupial osteology, this work proposes to study the aspects inherent to the skeleton of opossums, with emphasis on the detailed anatomical description of the bones that form the thoracic limb. For this purpose, the bones of six specimens of possums of the species Didelphis albiventris were used. These small to medium sized marsupials inhabit a wide range of South America, living in several types of habitats, being commonly described as arboreal omnivores and have anthropic habits. For the execution of this study, the bone accidents perceptible in the specimens were identified by superficial palpation, which were then radiographed. The thoracic limb bones were prepared by boiling and drying in the sun. Finally, from the radiographic images and the prepared bones, a detailed description of the anatomy of the bone components of the thoracic limb of Didelphis albiventris was made, joining the previously obtained data of surface anatomy. These data were compared with data from the literature, discussing the functional significance of the osteological findings of the thoracic limb of Didelphis albiventris.

RESUMEN: El esqueleto del miembro torácico es uno de los aspectos clave para el conocimiento de los hábitos y movimientos de las diferentes especies de mamíferos. Considerando los escasos estudios relacionados con la osteología marsupial, este trabajo se propusoestudiar los aspectos inherentes al esqueleto de la zarigüeya, con énfasis en la descripción anatómica detallada de los huesos que forman el miembro torácico. Para ello se utilizaron los huesos de seis ejemplares de zarigüeyas de la especie Didelphis albiventris. Estos marsupiales de pequeño a mediano tamaño habitan una zona amplia de América del Sur, viven en varios tipos de hábitats, se describen comúnmente como omnívoros arbóreos y tienen hábitos antrópicos. Para este estudio se identificaron mediante palpación superficial los accidentes óseos perceptibles en los especímenes, y posteriormente se tomaron imágens radiológicas. Los huesos de los miembros torácicos se prepararon hirviéndolos y secándolos al sol. Finalmente, a partir de las imágenes radiográficas y de los huesos preparados, se realizó una descripción detallada de la anatomía de los componentes óseos del miembro torácico de Didelphis albiventris, uniendo los datos de anatomía superficial obtenidos previamente. Estos datos se compararon con datos de la literatura, discutiendo la importancia funcional de los hallazgos osteológicos del miembro torácico de Didelphis albiventris.