Morphological and morphometric characteristics of the epididymis in the Neotropical bats Eumops glaucinus and Molossus molossus (Chiroptera: Molossidae).

The ability of certain species of bats to store viable spermatozoa in the cauda epididymis, for periods of many months beyond the end of spermatogenesis was first recognized over a century ago. However, information about the bat epididymis is still scarce or absent. Thus, this study aimed to characterize and to compare morphologically and morphometrically the regional histology of the epididymis of Eumops glaucinus and Molossus molossus (Chiroptera: Molossidae). Histologically, the epididymis of both species was subdivided into 4 segments: initial segment, caput, corpus and cauda. In comparing the two species, it was observed that the tubular and luminal diameters and percentage of interstitial tissue showed significant differences in all segments. The epithelial height, in both, is greater in the initial segment with a decrease until the cauda epididymis. In relation to the luminal diameter, both species showed a gradual increase from the initial segment to the cauda. The percentage of epithelium, lumen and interstitial tissue varied between both, sometimes M. molossus showing a significantly higher percentage, and other times, E. glaucinus. In both species, the principal cell was the most abundant (> 77%), followed by basal cells at approximately 13% and apical cells at 4% in all segments. Spermatozoa were observed in greater amounts in corpus and cauda epididymis segments. In summary, ours results show that, despite that the species analyzed belong to different genera and have different breeding cycles, the epididymis exhibits similarities in the two species and morphometric and composition differences compared to the majority of mammals.

Intrachromosomal distribution of telomeric repeats in Eumops glaucinus and eumops perotis (Molossidae, Chiroptera)

The location of chromosomal telomeric repeats (TTAGGG)(n) was investigated in two species of the Molossidae family, Eumops glaucinus and Eumops perotis. The diploid chromosome number (2n) is 40 in E. glaucinus and 48 in E. perotis and the fundamental numbers (FN) are 64 and 58, respectively. It has been suggested that the E. glaucinus karyotype has evolved from the E. perotis karyotype through Robertsonian fusion events. In the present study, the telomeric sequences were detected at the termini of chromosomes in both species. In addition, E. glaucinus also displayed telomeric repeats in centromeric and pericentromeric regions in almost all biarmed chromosomes. Conversely, in E. perotis pericentromeric signals were only observed in two biarmed chromosomes. In both E. glaucinus and E. perotis, such telomeric sequences were observed as part of the heterochromatin. The interstitial sites of telomeric sequences suggest that they are remnants of telomeres of ancestral chromosomes that participated in the fusion event.

In situ hybridization of bat chromosomes with human (TTAGGG)n probe, after previous digestion with Alu I

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Karyotypic patterns of seven species of molossid bats (Molossidae, Chiroptera)

G- and C- banding patterns of seven species of the bat family Molossidae, Eumops glaucinus, E. perotis; Molossops abrasus, M. remminckii, Molossus ater, M. molossus, and Nyctinomops laticaudatus, were identified. Comparisons among the karyotypes of these species showed extensive homologies between E. perotis, M. ater, M. molossus, M. abrasus, and N. laticaudatus, demonstrating inter- and intrageneric conservatism, and a lesser degree of homologies in M. temminckii and glaucinus, reflecting intrageneric variation, Chromosomal variation was due to inversions, Robertsonian rearrangements, translocations, and variations in the location of constitutive heterochromatin and nucleolus organizer regions. The chromosome corresponding to No. 5 in the M. ater karyotype is discussed. We suggest that the Nyctinomops and Molossops karyotypes represent the primitive condition and that Molossus and Eumops have derived karyotypes.

Genetic variability in species of bats revealed by RAPD analysis

Random amplified polymorphic DNA molecular marker was utilized as a means of analyzing genetic variability in seven bat species: Molossus molossus, M. rufus, Eumops glaucinus, E. perotis, Myotis nigricans, Eptesicus furinalis, and Artibeus planirostris. The determination of genetic diversity was based on 741 bands produced by a 20-random primer set. Only eight bands were considered monomorphic to one species. The greatest number of bands and the most polymorphic condition were exhibited by M. molossus, followed by M. nigricans, A. planirostris, E. furinalis, E. glaucinus, M. rufus, and E. perotis. Nei's genetic diversity index in the seven species considering the 20 primers was not greater than 0.22, but some primers were capable of detecting values between 0.39 and 0.49. Nei's unbiased genetic distance values and the UPGMA clustering pattern show that M. molossus and M. rufus have a close genetic relationship, unlike that observed between E. perotis and E. glaucinus. The latter was clustered with A. planirostris and E. furinalis. The low values for genetic diversity and distance observed indicate a genetic conservatism in the seven species. The fluorescent in situ hybridization experiments did not confirm a monomorphic condition for the eight bands identified, demonstrating that the monomorphic bands obtained by random amplified polymorphic DNA are insufficient for the identification of bat species.

Análise de marcadores moleculares RAPD em espécie de morcegos dos gêneros Eumops, Molossus, Eptesicus, Myotis e Artibeus (Chiroptera, Mammalia)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Antigenic and genetic characterization of the first rabies virus isolated from the bat Eumops perotis in Brazil

Although the main transmitters of rabies in Brazil are dogs and vampire bats, the role of other species such as insectivorous and frugivorous bats deserves special attention, as the rabies virus has been isolated from 36 bat species. This study describes the first isolation of the rabies virus from the insectivorous bat Eumops perotis. The infected animal was found in the city of Ribeirão Preto, São Paulo. The virus was identified by immunofluorescence antibody test (FAT) in central nervous system (CNS) samples, and the isolation was carried out in N2A cell culture and adult mice. The sample was submitted to antigenic typing using a panel of monoclonal antibodies (CDC/Atlanta/USA). The DNA sequence of the nucleoprotein gene located between nucleotides 102 and 1385 was aligned with homologous sequences from GenBank using the CLUSTAL/W method, and the alignment was used to build a neighbor-joining distance-based phylogenetic tree with the K-2-P model. CNS was negative by FAT, and only one mouse died after inoculation with a suspension from the bat's CNS. Antigenic typing gave a result that was not compatible with the patterns defined by the panel. Phylogenetic analysis showed that the virus isolated segregated into the same cluster related to other viruses isolated from insectivorous bats belonging to genus Nyctinomops ssp. (98.8% nucleotide identity with each other).

Vírus da raiva em quirópteros naturalmente infectados no Estado de São Paulo, Brasil

OBJETIVO: Identificar as espécies de morcegos envolvidas na manutenção do ciclo da raiva, verificar a distribuição do vírus da raiva em tecidos e órgãos de morcegos e os períodos de mortalidade dos camundongos inoculados. MÉTODOS: A positividade para o vírus da raiva foi avaliada por imunofluorescência direta em morcegos de municípios do Estado de São Paulo, de abril de 2002 a novembro de 2003. A distribuição do vírus nos morcegos foi avaliada pela inoculação de camundongos e infecção de células N2A, com suspensões a 20% preparadas a partir de fragmentos de diversos órgãos e tecidos, além de cérebro e glândula salivar. A mortalidade dos camundongos foi observada diariamente, após inoculação intracerebral. RESULTADOS: Dos 4.393 morcegos pesquisados, 1,9% foram positivos para o vírus da raiva, pertencentes a dez gêneros, com predomínio de insetívoros. A média do período máximo de mortalidade dos camundongos pós-inoculação a partir de cérebros e glândulas salivares de morcegos hematófagos foi de 15,33±2,08 dias e 11,33±2,30 dias; insetívoros, 16,45±4,48 dias e 18,91±6,12 dias; e frugívoros, 12,60±2,13 dias e 15,67±4,82 dias, respectivamente. CONCLUSÕES: As espécies infectadas com o vírus da raiva foram: Artibeus lituratus, Artibeus sp., Myotis nigricans, Myotis sp., Eptesicus sp., Lasiurus ega, Lasiurus cinereus, Nyctinomops laticaudatus, Tadarida brasiliensis, Histiotus velatus, Molossus rufus, Eumops sp. e Desmodus rotundus. A pesquisa de vírus em diferentes tecidos e órgãos mostrou-se que os mais apropriados para o isolamento foram cérebro e glândulas salivares.

Rabies diagnosis and serology in bats from the State of São Paulo, Brazil

INTRODUCTION: Bats are one of the most important reservoirs and vectors of the rabies virus in the world. METHODS: From 1988 to 2003, the Zoonosis Control Center in São Paulo City performed rabies diagnosis on 5,670 bats by direct immunofluorescent test and mouse inoculation test. Blood samples were collected from 1,618 bats and the sera were analyzed using the rapid fluorescent focus inhibition test to confirm rabies antibodies. RESULTS: Forty-four (0.8%) bats were positive for rabies. The prevalence of rabies antibodies was 5.9% using 0.5IU/ml as a cutoff. Insectivorous bats (69.8%) and bats of the species Molossus molossus (51.8%) constituted the majority of the sample; however, the highest prevalence of antibodies were observed in Glossophaga soricina (14/133), Histiotus velatus (16/60), Desmodus rotundus (8/66), Artibeus lituratus (5/54), Nyctinomops macrotis (3/23), Tadarida brasiliensis (3/48), Carollia perspicillata (3/9), Eumops auripendulus (2/30), Nyctinomops laticaudatus (2/16), Sturnira lilium (2/17) and Eumops perotis (1/13). The prevalence of rabies antibodies was analyzed by species, food preference and sex. CONCLUSIONS: The expressive levels of antibodies associated with the low virus positivity verified in these bats indicate that rabies virus circulates actively among them.

Algumas investigações sobre Schizotrypanum de Quirópteros

Os autores referem as especies de morcegos de diversos países americanos, emque foi pesquisada no sangue a presença de hemoflagelados. Tripanosomas com a morfologia das formas sanguicolas de Schizotrypanum foram encontrados, tendo sido colhidos dados novos sobre a distribuição geografica e a incidencia da infecção em diferentes especies de morcegos. Sómente nos tecidos do Phyllostomus hastatus puderam ser encontradas as formas de multiplicação do flagelado. Alimentando-se exemplares de Triatoma infestans em Eumops bonariensis beckeri infectado, foi obtido desenvolvimento intestinal do parasito. Por inoculação das vinchucas assim infectadas em camondongo, conseguiu-se facilmente transmissão da infecção a este animal. Inoculando-se cultura do Schizotrypanum de Phyllostomus hastatus em coelho, por via subcutanea, verificaram-se no ponto de inoculação, 5 dias depois, celulas contendo tipicas formas de leishmania. São assinalados fatos observados sobre a associação demorcegos com Hemipteros sugadores (Reduvideos e Cimicideos), os quais, pela circunstancia de se poderem infectar pelo flagelado, são os possiveis transmissores da infecção a estes mamiferos.

Assessing genetic variability in bat species of Emballonuridae, Phyllostomidae, Vespertilionidae and Molossidae families (Chiroptera) by RFLP-PCR

A PCR-RFLP analysis of the restriction pattern in nuclear (RAG2) and mitochondrial (12S/16S) gene sequences of bat species from the Molossidae, Phyllostomidae, Vespertilionidae, and Emballonuridae families produced a large number of fragments: 107 for RAG2 and 155 for 12S/16S combined in 139 and 402 haplotypes, respectively. The values detected for gene variation were low for both sequences (0.13 for RAG2 and 0.15 for 12S/16S) and reflected their conservative feature, reinforced by high values of inter- and intraspecies genetic identity (70-100%). The species with a high gene divergence were variable in the analyses of RAG2 (Eumops perotis, Artibeus lituratus, and Carollia perspicillata) and of 12S/16S (Nyctinomops laticaudatus, C. perspicillata, and Cynomops abrasus), and furthermore, one of them, C. perspicillata, also showed the highest intraspecific variation. The species that exhibited the lowest variation for both genes was Molossus rufus. In the families, the highest variation was observed in the Molossidae and this can be attributed to variation exhibited by Eumops and Nyctinomops species. The variations observed were interpreted as a natural variability within the species and genus that exhibited a conserved pattern in the two gene sequences in different species and family analyzed. Our data reinforce the idea that the analyses of mitochondrial and nuclear genes contribute to our knowledge of the diversity of New World bats. The genetic variability found in different taxa suggests that an additional diversity, unnoticed by other methods, can be revealed with the use of different molecular strategies. ©FUNPEC-RP.

New insights into telomeric DNA sequence (TTAGGG)n location in bat chromosomes

Molossidae species, Cynomops abrasus (2n = 34, fundamental number, FN = 64), Eumops auripendulus (2n = 42, FN = 62), Molossus rufus (2n = 48, FN = 64), Molossops temminckii (2n = 48, FN = 64), and Nyctinomops laticaudatus (2n = 48, FN = 64), and Phyllostomidae species, Phyllostomus discolor (2n = 32, FN = 60), have karyotypes with different chromosome and fundamental numbers, different localization of constitutive heterochromatin, and different numbers and location of nucleolar organizer regions (NORs). Fluorescence in situ hybridization with a human probe of the telomeric sequence (TTAGGG)n produced fluorescent signals in telomeric regions of the six bat species' chromosomes; in E. auripendulus, pericentromeric signals were also observed in the acrocentric and subtelocentric chromosomes. A relationship between telomeric sequences and NORs, and between telomeric sequences and constitutive heterochromatin was detected in chromosomes bearing NORs in C. abrasus, M. temminckii, N. laticaudatus, and P. discolor. No interstitial signal was observed in the meta- or submetacentric chromosomes of these species. ©FUNPEC-RP.

Histomorfologia da glande peniana e do báculo de morcegos molossideos e vespertilionideos: uma abordagem comparativa (Chiroptera, Mammalia)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)