Consulta: creatorFacets:"Galetti Jr.,Pedro Manoel"
Registros recuperados: 6
Data/hora: 05/06/2024 14:27:04

RAPD markers indicate the occurrence of structured populations in a migratory freshwater fish species
Provedor de dados: 74
Autores: Hatanaka,Terumi; Galetti Jr.,Pedro Manoel.
Many factors have contributed to the destruction of fish habitats. Hydroelectric dams, water pollution and other environmental changes have resulted in the eradication of natural stocks. The aim of this study was to detect the genetic variation in Prochilodus marggravii from three collection sites in the area of influence of the Três Marias dam (MG) on the São Francisco river (Brazil), using the RAPD technique. The results obtained revealed that the fish in the downstream region nearest the dam have a higher similarity coefficient than those from the other sampling sites that may be related to differences in environmental characteristics in these regions. Additionaly, significant differences in the band frequencies were observed from one collection site to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Prochilodus; RAPD; Genetic structure; Conservation genetic; Fish.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000100004

Chromosomal evidence of population subdivision in the freshwater fish Leporinus elongatus in the Upper Paraná River basin
Provedor de dados: 74
Autores: Molina,Wagner Franco; Shibatta,Oscar; Galetti Jr.,Pedro Manoel.
Cytogenetic analyses performed in populations of the Neotropical freshwater fish Leporinus elongatus of the Upper Paraná River basin showed a chromosome polymorphism involving heterochromatic segments of the nucleolar organizing pair in this species. The NOR-bearing chromosome pair was characterized by two phenotypes identified by the absence (C¹) or presence (C²) of a heterochromatic segment located in an interstitial position of the long arm in this pair. The meiotic segregation of these variations results in three distinct cytotypes, C¹C¹, C¹C² and C²C². Both populations were in Hardy-Weinberg equilibrium. Sex-related cytotype divergence was identified and multivariate analyses revealed that the C²C² individuals presented morphometric differentiation...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Characiformes; Anostomidae; Heterochromatin; Chromosome polymorphism.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200020

Karyotype similarity between two sympatric Schizodon fish species (Anostomidae, Characiformes) from the Paraguay River basin
Provedor de dados: 74
Autores: Martins,Cesar; Galetti Jr.,Pedro Manoel.
Fish of the neotropical family Anostomidae generally show low karyotype variability. Nevertheless, karyotype variants have been identified within some genera, providing information about their evolutionary history. Species of the genus Schizodon show a high degree of morphological and ecological similarity compared to other anostomids. In the present study, karyotype characteristics of Schizodon borelli (40 individuals) and S. isognathum (one individual), two sympatric species found in the Paraguay River basin, were studied. C-banding, GC-specific fluorochrome Mitramycin (MM) and Ag staining as well as in situ hybridization (FISH) with rDNA probes were used. The karyotypes of these species were found to be very similar. Only two NORs were detected in a...
Tipo: Info:eu-repo/semantics/article
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000300011

Mapping 18S ribosomal genes in fish of the genus Brycon (Characidae) by fluorescence in situ hybridization (FISH)
Provedor de dados: 74
Autores: Wasko,Adriane Pinto; Galetti Jr.,Pedro Manoel.
The present study provides data on the nucleolar organizer regions (NORs) of seven Brycon species based on mapping of the 18S rRNA genes by fluorescence in situ hybridization (FISH). Fluorescent signals were observed on the telomere of the long arm of two large submetacentric chromosomes, thus confirming the number and location of NORs previously revealed by other classical cytogenetic techniques. Although there were no inter- or intra-individual variations in the number and location of the 18S loci, NOR size polymorphism was observed between homologous chromosomes. The clustering and conservation of NORs in a single chromosome pair indicates a high level of NOR stability among species of the genus Brycon.
Tipo: Info:eu-repo/semantics/article
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572000000100025

Multiple pericentric inversions and chromosomal divergence in the reef fishes Stegastes (Perciformes, Pomacentridae)
Provedor de dados: 74
Autores: Molina,Wagner Franco; Galetti Jr.,Pedro Manoel.
Damselfishes (Pomacentridae, Perciformes) occur in all major oceans of the world and, with approximately 320 species, represent one of the most diverse families of marine Teleostei. The taxonomy of these reef fishes is problematic because of the large number of complex species and the range of color patterns they display, which vary among individuals and populations of the same species. In this study, we examined the cytogenetic composition of four species of Stegastes (S. pictus, S. fuscus, S. variabilis and S. leucostictus) found along the coast of Brazil. Stegastes pictus had a chromosomal number of 2n = 48 (14m+28sm+2st+4a, fundamental number (FN) = 92), S. fuscus had 2n = 48 (20m+22sm+6a, FN = 90), S. variabilis had 2n = 48 (18m+22sm+8a, FN = 88), and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pericentric inversions; Pomacentridae; Stegastes; 5S genes.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000400013

Re-discovering jaguar in remaining coastal Atlantic Forest in southeastern Brazil by non-invasive DNA analysis
Provedor de dados: 49
Autores: Souza,Andiara Silos Moraes de Castro; Saranholi,Bruno Henrique; Crawshaw Jr.,Peter Gransden; Paviolo,Agustin Javier; Rampim,Lilian Elaine; Sartorello,Leonardo; Galetti Jr.,Pedro Manoel.
Abstract Jaguar populations have been declining in Brazil mostly due to habitat loss and fragmentation, conflict with humans, poaching and reduction of prey. This is dramatically true in the Atlantic Forest, where occurrence of this large felid is now restricted to very few remaining areas. We used a non-invasive DNA analysis to search through felid scats collected in the Santa Virginia Unit (SVU) of the Serra do Mar State Park, to test for the potential presence of jaguar there. Our results indicated at least three individuals (two females and one male) inside SVU, thus confirming at least temporary presence of this top predator in this important protected area. It is now crucial to intensify studies in that area and surroundings, to evaluate the status...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Panthera onca; Fecal DNA; Santa Virginia Unit; Serra do Mar State Park.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032017000200501