Mammals In Brazil Research Articles

Molecular characterization of Capim and Enseada orthobunyaviruses

Capim and Enseada viruses are members of the genus Orthobunyavirus isolated from mosquitoes and mammals in Brazil. Despite seroprevalence studies indicating human infections in Latin America, these viruses remain relatively unknown and unstudied. In order to better understand the genetic and evolutionary relationships among orthobunyaviruses, we sequenced the three genomic segments of Capim and Enseada orthobunyaviruses. Based on phylogenetic analysis, we demonstrated that these viruses depicted two new distinct clades, one represented by Enseada and another composed of Capim virus. In general, the genome organization and genetic traits of these viruses are similar to other orthobunyaviruses however, the open reading frame (ORF) of the putative nonstructural NSs protein of Enseada orthobunyavirus precedes the nucleocapsid ORF. Overall, our study provides details on the molecular characteristics of the prototype species of two groups within the Orthobunyavirus genus, revealing novel features into the genetic diversity and evolution of this genus.

Novel Babesia and Hepatozoon agents infecting non-volant small mammals in the Brazilian Pantanal, with the first record of the tick Ornithodoros guaporensis in Brazil

Taking into account the diversity of small terrestrial mammals of the Pantanal, the present study aimed to verify the occurrence of infection by Ehrlichia spp., Anaplasma spp., Rickettsia spp., Hepatozoon spp., Babesia spp. and parasitism by ticks in non-volant small mammals collected in the Brazilian Pantanal. Samples of blood, liver and spleen were collected from 64 captured animals, 22 marsupials and 42 rodents. Pathogen detection was performed by the use of genus-specific Polymerase Chain Reaction (PCR) assays. Ticks collected from the animals consisted of Amblyomma sculptum and Amblyomma triste nymphs, and Ornithodoros guaporensis larvae. None of the vertebrate samples (blood, liver, or spleen) yielded detectable DNA of Rickettsia spp. or Ehrlichia spp. The blood of the rodent Hylaeamys megacephalus yielded an Anaplasma sp. genotype (partial 16S rRNA gene) 99% similar to multiple Anaplasma spp. genotypes around the world. The blood of three rodents of the species Calomys callosus were positive for a novel Hepatozoon sp. agent, phylogenetically related (18S rDNA gene) to distinct Hepatozoon genotypes that have been detected in rodents from different parts of the world. One marsupial (Monodelphis domestica) and three rodents (Thrichomys pachyurus) were positive to novel piroplasmid genotypes, phylogenetically (18S rDNA gene) related to Theileria bicornis, Cytauxzoon manul, and Cytauxzoon felis. The present study provides the first molecular detection of Hepatozoon sp. and piroplasmids in small mammals in Brazil. Additionally, we expanded the distribution of O. guaporensis to Brazil, since this tick species was previously known to occur only in Bolivia.

New species and records of mites of the superfamily Sarcoptoidea (Acariformes: Psoroptidia) from mammals in Brazil.

Sixteen species of the superfamily Sarcoptoidea (Acariformes: Psoroptidia) belonging to 10 genera of the families Atopomelidae, Listrophoridae, Chirodiscidae, and Listropsoralgidae are recorded in Brazil. Among them, three species, Prolistrophorus hylaeamys sp. nov. from Hylaeamys laticeps (Lund, 1840) (Cricetidae: Sigmodontinae) from Minas Gerais, Lynxacarus serrafreirei sp. nov. from Galictis cuja (Molina, 1782) (Carnivora: Mustelidae) from Rio de Janeiro (Listrophoridae), and Didelphoecius micoureus sp. nov. (Atopomelidae) from Micoureus paraguayanus (Tate, 1931) (Didelphimorphia: Didelphidae) from Minas Gerais are described as new for science. Three species of the family Listrophoridae, Prolistrophorus bidentatus Fain et Lukoschus, 1984 from Akodon cursor (Winge, 1887) (Rodentia: Cricetidae) (new host), Prolistrophorus ctenomys Fain, 1970 from Ctenomys torquatus Lichtenstein, 1830 (Rodentia: Ctenomyidae) (new host), and Leporacarus sylvilagi Fain, Whitaker et Lukoschus, 1981 from Sylvilagus brasiliensis (Linnaeus, 1758) (Lagomorpha: Leporidae) (new host) -from Minas Gerais and Rio Grande do Sul, and one species of the family Chirodiscidae, Parakosa tadarida McDaniel and Lawrence, 1962 from Molossus molossus (Pallas, 1766) (Chiroptera: Molossidae) are recorded for the first time in Brazil. The previously unknown female of Didelphoecius validus Fain, Zanatta-Coutinho et Fonseca, 1996 (Atopomelidae) from Metachirus nudicaudatus (Geoffroy, 1803) (Didelphimorphia: Didelphidae) from Minas Gerais is described. All data on host-parasite associations of sarcoptoids in Brazil are summarized. Totally, 61 sarcoptoid species of 8 families are recorded in Brazil.

Cleaning associations between birds and herbivorous mammals in Brazil: Structure and complexity

ABSTRACT. Birds that remove ectoparasites and other food material from their hosts are iconic illustrations of mutualistic—commensalistic cleaning associations. To assess the complex pattern of food resource use embedded in cleaning interactions of an assemblage of birds and their herbivorous mammal hosts in open habitats in Brazil, we used a network approach that characterized their patterns of association. Cleaning interactions showed a distinctly nested pattern, related to the number of interactions of cleaners and hosts and to the range of food types that each host species provided. Hosts that provided a wide range of food types (flies, ticks, tissue and blood, and organic debris) were attended by more species of cleaners and formed the core of the web. On the other hand, core cleaner species did not exploit the full range of available food resources, but used a variety of host species to exploit these resources instead. The structure that we found indicates that cleaners rely on cleaning interactions...

Morphological and molecular analysis of Ornithonyssus spp. (Acari: Macronyssidae) from small terrestrial mammals in Brazil

Based on chaetotaxy of the dorsal shield, the taxonomic status of many species of Ornithonyssus has been considered invalid, resulting in the synonymy of all Brazilian Ornithonyssus from small terrestrial wild mammals into one of the following four species: Ornithonyssus bacoti (Hirst, 1913), Ornithonyssus matogrosso (Fonseca, 1954), Ornithonyssus pereirai (Fonseca, 1935) or Ornithonyssus wernecki (Fonseca, 1935). Despite the revision of this genus in 1980, including all known species worldwide, the knowledge of Ornithonyssus in Brazil has not progressed for more than 40years. Considering the potential importance of these haematophagous mites in transmitting rickettsial disease agents to animals and humans, we have revised Ornithonyssus species collected from small mammals in Brazil by means of morphological and molecular studies. Types and other material deposited in the Acari Collection of the Instituto Butantan (IBSP) were examined in addition to recently collected specimens. Morphological and genetic analysis of the 16S rDNA mitochondrial gene revealed that small terrestrial mammals in Brazil are parasitized by six species of Ornithonyssus mites: Ornithonyssus brasiliensis (Fonseca, 1939), O. matogrosso, O. monteiroi (Fonseca, 1941), O. pereirai, O. vitzthumi (Fonseca, 1941), and O. wernecki. An illustrated key to females of the valid Brazilian species of Ornithonyssus is included, based on optical and scanning electron microscopy.

Human Intraocular Filariasis Caused byDirofilariasp. Nematode, Brazil

A case of human intraocular dirofilariasis is reported from northern Brazil. The nematode was morphologically and phylogenetically related to Dirofilaria immitis but distinct from reference sequences, including those of D. immitis infesting dogs in the same area. A zoonotic Dirofilaria species infesting wild mammals in Brazil and its implications are discussed.

Genetic diversity among capybara (Hydrochaeris hydrochaeris) isolates of Toxoplasma gondii from Brazil

Recent studies indicate that Toxoplasma gondii isolates of many domestic hosts from Brazil are genetically and biologically different from T. gondii isolates from USA and Europe. However, little is known about genetics of T. gondii isolates from wild mammals in Brazil. In this study, genotypes of 36 T. gondii isolates from capybaras (Hydrochaeris hydrochaeris) from six counties in São Paulo state, Brazil, were determined. Sixteen genotypes were identified using 11 genetic markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3. No classical clonal Type I and Type II isolates were found, confirming other findings that these lineages are rare in Brazil. Eight of these 36 isolates were grouped into the common clonal lineages in Brazil, previously designed as Types BrI, BrII and BrIII. Seven of the 16 genotypes were reported for the first time in this study. Three of the 36 isolates showed mixed infections. Analysis of mortality rates in infected mice indicated that Type BrI is highly virulent, Type BrII is intermediately virulent and Type BrIII is non-virulent, which is in agreement with previous report. The allele types at the CS3 locus are strongly linked to mouse-virulence of the parasite. These genotyping results support previous findings that the T. gondii population is highly diverse in Brazil.

Uso do espaço por pequenos mamíferos: uma análise dos estudos realizados no Brasil

Normal 0 21 false false false MicrosoftInternetExplorer4 Utilization of space refers to the intensity of exploitation of a habitat by a species, including the amount and quality of the exploited habitat. It is an important factor driving the abundance and distribution of animal species. Brazilian small mammals have been used as models to evaluate space utilization by tropical mammals in general, but it is yet unclear whether knowledge about the species, biomes, different aspects of space use, and even the techniques being employed in Brazil are representative of other regions. The present study presents a review of studies on space utilization by small mammals in Brazil published from 1945 to 2007. Fifty-eight publications were found, most of which were conducted in the Atlantic Forest (65%). Within this biome, marsupials were the most common taxon examined (86%) followed by rodents (53%). In the Cerrado, these figures changed to 44% and 100%, respectively. Only 14% of the studies dealt with vertical utilization of space. The great majority of the publications (75%) used capture-mark-recapture methods with live traps (CMR). Current knowledge of space utilization by Brazilian small mammals was mainly based on few genera from a single biome -- the Atlantic Forest -- using a technique that records only part of the movement patterns of these animals (CMR). Future studies that fill the gaps indicated here will hopefully allow the detection and establishment of more general patterns of space use by tropical mammals.

Mammal Conservation in Brazil

Abstract: Brazil is the fifth largest country in the world and the first of the megadiversity countries, accounting for roughly 14% of the world's biota. It has the largest mammal diversity (more than 530 described species) with many yet to be discovered and cataloged. Very few sites have been adequately surveyed, and local lists are usually incomplete, which makes for knowledge gaps that hamper conservation and management initiatives and regional analyses. According to the Brazilian Institute for the Environment (IBAMA), 66 species are threatened, and the World Conservation Union lists 74. Primates, mostly Atlantic Forest endemics, are the most endangered group (40% of the threatened taxa). Carnivores and rodents are also notable members of the lists. Twenty‐nine percent of listed species are marine, 18% occur in the Atlantic Forest, 13% in the Pampas, 12% in the Cerrado, 11% in the Pantanal, 7% in the Amazon, and 6% in the Caatinga. Human‐induced habitat loss and fragmentation are major threats to land mammals in Brazil, and large‐ and medium‐sized mammals are hunted. The major threat to small mammals is the scarcity of basic scientific knowledge—taxonomy, systematics, distribution, and natural history. Aquatic mammals are threatened by commercial hunting, accidental netting, long‐line fisheries, chemical pollution, habitat degradation, tourism, and boat traffic. Mammal conservation has benefited from a number of recent initiatives by government and nongovernmental organizations, including legislation, nationwide initiatives to define priority areas for conservation, management plans for some threatened species, sustainable landscape planning, and new protected areas. Given the rate of habitat loss, a nationwide program of short‐ and long‐term field surveys and increased support for natural history collections is of particularly urgency. Progress has been made toward conserving Brazilian mammals in recent years, but threats are growing fast, and conservation science must keep growing to provide the wherewithal to minimize and remove these threats.

Differential trappability of small mammals in three habitats of Southeastern Brazil

We compared the trappability of marked and unmarked individuals in species of marsupials and rodents of three tropical assemblages of small mammals in Brazil. Two studies used trapping grids, one in cerrado and the other in an Atlantic forest reserve, whereas the study in a rural area used transects. In the two studies using trapping grids, marked animals were frequently more trappable than unmarked ones, but in some species this difference was not significant. In the rural area, marked and unmarked animals did not differ significantly. The number of recaptures per resident animal was higher in the two studies using trapping grids than in the rural area where transects were used. Differences in trappability between the three studies might have been caused by differences not only in trapping design (grids vs. transects), but also in the type of trap used, bait, and habitat. Although differential trappability tends to be considered the rule in small mammals, these results suggest that trappability of marked and unmarked animals may be specific for the particular combination of sampling design, field methods, and habitat under study.

Strandings of Antillean manatees, <i>Trichechus manatus manatus</i>, in northeastern Brazil

The Antillean manatee (Trichechus manatus manatus) is considered to be one of the most endangered aquatic mammals in Brazil. From 1981 through 2002 an extensive research was performed to collect information about stranding of manatees of the northeast coast of Brazil. Data were separated in two distinct periods (1981-1990 and 1991-2002) and analyzed according to specific categories: stranded dead (captured by nets, captured by harpoons and undefined cause) and stranded alive (dead in captivity and captive population). There were 74 events of stranding manatees in the period surveyed. Thirty-one events of dead manatees and 43 events of specimens that survived until December, 2002 were recorded. In the last years of the study there were more strandings of live animals than dead. The main reason for the strandings of manatee calves in northeastern Brazil is the separation from their mothers. The largest numbers of stranded manatees occurred in Ceará and Rio Grande do Norte states.

Ectoparasites Ixodida Leach, 1817 on wild mammals in the state of Paraná, Brazil

A taxonomical and ecological study was made on 264 samples of 12 species of ectoparasite ixodides collected on wild mammals from several natural regions of Paraná state, Brazil. These species of ticks as their hosts are listed by their identified evolutive forms and capture locations. A review of the early studies on the Ixodida from South Brazil is made considering the frequency of the parasite species on each host concerning the geographic distribution of such species. This paper is a contribution to the knowledge of the Ixodidae ectoparasites species of wild mammals in Brazil.