Consulta: creatorFacets:"Gunski,Ricardo José"
Registros recuperados: 15
Data/hora: 01/06/2024 00:39:36

Karyotypic evolution of ribosomal sites in buffalo subspecies and their crossbreed
Provedor de dados: 74
Autores: Degrandi,Tiago Marafiga; Pita,Sebastian; Panzera,Yanina; Oliveira,Edivaldo Herculano C. de; Marques,José Ribamar Felipe; Figueiró,Marivaldo Rodrigues; Marques,Larissa Coêlho; Vinadé,Lucia; Gunski,Ricardo José; Garnero,Analía Del Valle.
Domestic buffaloes are divided into two group based on cytogenetic characteristics and habitats: the "river buffaloes" with 2n = 50 and the "swamp buffaloes", 2n = 48. Nevertheless, their hybrids are viable, fertile and identified by a 2n = 49. In order to have a better characterization of these different cytotypes of buffaloes, and considering that NOR-bearing chromosomes are involved in the rearrangements responsible for the karyotypic differences, we applied silver staining (Ag-NOR) and performed fluorescent in situ hybridization (FISH) experiments using 18S rDNA as probe. Metaphases were obtained through blood lymphocyte culture of 21 individuals, including river, swamp and hybrid cytotypes. Ag-NOR staining revealed active NORs on six chromosome pairs...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: 18S rDNA; Bubalus bubalis; FISH.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572014000300009

Polymorphism of Sooty-fronted Spinetail (Synallaxis frontalis Aves: Furnariidae): Evidence of chromosomal rearrangements by pericentric inversion in autosomal macrochromosomes
Provedor de dados: 74
Autores: Souza,Marcelo Santos de; Barcellos,Suziane Alves; Costa,Alice Lemos; Kretschmer,Rafael; Garnero,Analía Del Valle; Gunski,Ricardo José.
Abstract The Passeriformes is the most diverse and cytogenetically well-known clade of birds, comprising approximately 5,000 species. The sooty-fronted spinetail (Synallaxis frontalis Aves: Furnariidae) species, which belongs to the order Passeriformes, is typically found in South America, where it is widely distributed. Polymorphisms provide genetic variability, important for several evolutionary processes, including speciation and adaptation to the environment. The aim of this work was to analyze the possible cytotypes and systemic events involved in the species polymorphism. Of the sampled 19 individuals, two thirds were polymorphic, an event supposedly linked to mutations resulting from genomic evolution that can be transmitted hereditarily. A...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosomal polymorphism; Evolution; Cytogenetics.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572019000100062

Repetitive DNAs and shrink genomes: A chromosomal analysis in nine Columbidae species (Aves, Columbiformes)
Provedor de dados: 74
Autores: Kretschmer,Rafael; de Oliveira,Thays Duarte; de Oliveira Furo,Ivanete; Oliveira Silva,Fabio Augusto; Gunski,Ricardo José; del Valle Garnero,Analía; de Bello Cioffi,Marcelo; de Oliveira,Edivaldo Herculano Corrêa; de Freitas,Thales Renato Ochotorena.
Abstract An extensive karyotype variation is found among species belonging to the Columbidae family of birds (Columbiformes), both in diploid number and chromosomal morphology. Although clusters of repetitive DNA sequences play an important role in chromosomal instability, and therefore in chromosomal rearrangements, little is known about their distribution and amount in avian genomes. The aim of this study was to analyze the distribution of 11 distinct microsatellite sequences, as well as clusters of 18S rDNA, in nine different Columbidae species, correlating their distribution with the occurrence of chromosomal rearrangements. We found 2n values ranging from 76 to 86 and nine out of 11 microsatellite sequences showed distinct hybridization signals among...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Birds; FISH; Microsatellites; Sex chromosomes; Chromosomal rearrangements.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000100098

Cytogenetic comparison of Podocnemis expansa and Podocnemis unifilis: a case of inversion and duplication involving constitutive heterochromatin
Provedor de dados: 74
Autores: Gunski,Ricardo José; Cunha,Isabel Souza; Degrandi,Tiago Marafiga; Ledesma,Mario; Garnero,Analía Del Valle.
Podocnemis expansa and P. unifilis present 2n = 28 chromosomes, a diploid number similar to those observed in other species of the genus. The aim of this study was to characterize these two species using conventional staining and differential CBG-, GTG and Ag-NOR banding. We analyzed specimens of P. expansa and P. unifilis from the state of Tocantins (Brazil), in which we found a 2n = 28 and karyotypes differing in the morphology of the 13th pair, which was submetacentric in P. expansa and telocentric in P. unifilis. The CBG-banding patterns revealed a heterochromatic block in the short arm of pair 13 of P. expansa and an interstitial one in pair 13 of P. unifilis, suggesting a pericentric inversion. Pair 14 of P. unifilis showed an insterstitial band in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosome banding; Ag-NORs; Karyotype; Chelonids.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000300009

Chromosomal polymorphism and comparative chromosome painting in the rufous-collared sparrow (Zonotrichia capensis)
Provedor de dados: 74
Autores: Bülau,Sandra Eloisa; Kretschmer,Rafael; Gunski,Ricardo José; Garnero,Analía del Valle; O’Brien,Patricia C. M.; Ferguson-Smith,Malcolm A.; Oliveira,Edivaldo Herculano Correa de; Freitas,Thales Renato Ochotorena de.
Abstract Zonotrichia capensis is widely distributed in the Neotropics. Previous cytogenetic studies demonstrated the presence of polymorphisms in two chromosome pairs (ZCA2 and ZCA4). Here, we report results based on comparative chromosome painting, using probes derived from Gallus gallus and Leucopternis albicollis, focused on characterizing the chromosome organization of Z. capensis. Our results demonstrate the conservation of ancestral syntenies as observed previously in other species of passerine. Syntenies were rearranged by a series of inversions in the second chromosome as described in other Passeriformes, but in this species, by using probes derived from L. albicollis we observed an extra inversion in the second chromosome that had not previously...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Birds; Chromosomal rearrangements; Molecular cytogenetics; FISH.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000500799

Comparative analyses of three swallow species (Aves, Passeriformes, Hirundinidae): Insights on karyotype evolution and genomic organization
Provedor de dados: 74
Autores: Barcellos,Suziane Alves; Kretschmer,Rafael; Souza,Marcelo Santos de; Costa,Alice Lemos; Degrandi,Tiago Marafiga; Lopes,Cassiane Furlan; Ferguson-Smith,Malcolm A.; Pereira,Jorge; Oliveira,Edivaldo Herculano Correa de; Gunski,Ricardo José; Garnero,Analía del Valle.
Abstract Despite the richness of species in the Hirudinidae family, little is known about the genome organization of swallows. The Progne tapera species presents genetic and morphological difference when compared to other members of the same genus. Hence, the aims of this study were to analyze the chromosomal evolution of three species Progne tapera, Progne chalybea and Pygochelidon cyanoleuca - by comparative chromosome painting using two sets of probes, Gallus gallus and Zenaida auriculata, in order to determine chromosome homologies and the relationship between these species. All karyotypes exhibited 76 chromosomes with similar morphology, except for the 5th, 6th and 7th chromosome pairs in P. cyanoleuca. Additionally, comparative chromosome painting...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Homology; Molecular cytogenetics; Fluorescent in situ hybridization; Hirundinidae.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572020000100201

Nucleolar organizer regions and a new chromosome number for Rhea americana (Aves: Rheiformes)
Provedor de dados: 74
Autores: Gunski,Ricardo José; Giannoni,Miriam Luz.
Sequential banding analysis (Giemsa-C-banding-Ag NOR) of chromosomes of the common rhea (Rhea americana) was performed. Metaphases were obtained by peripheral blood lymphocyte culture and monolayer embryo cell culture. The diploid chromosome number was 80, different from the 2n = 82 in previous reports. Macrochromosome pairs 1, 2 and 5 were submetacentric and pair 3, subacrocentric. The 4th pair was acrocentric and all of the microchromosomes appeared to be acrocentric, with the exception of a clearly metacentric pair which was fully heterochromatic. The Z was slightly larger than the W, both being acrocentric and C-band negative. Nucleolar organizer regions were observed in the secondary constriction of a microchromosome pair. Correct identification of...
Tipo: Info:eu-repo/semantics/article
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000200006

Nucleolar organizer regions in Sittasomus griseicapillus and Lepidocolaptes angustirostris (Aves, Dendrocolaptidae): evidence of a chromosome inversion
Provedor de dados: 74
Autores: Barbosa,Marcelo de Oliveira; Silva,Rubens Rodrigues da; Correia,Vanessa Carolina de Sena; Santos,Luana Pereira dos; Garnero,Analía del Valle; Gunski,Ricardo José.
Cytogenetic studies in birds are still scarce compared to other vertebrates. Woodcreepers (Dendrocolaptidae) are part of a highly specialized group within the Suboscines of the New World. They are forest birds exclusive to the Neotropical region and similar to woodpeckers, at a comparable evolutionary stage. This paper describes for the first time the karyotypes of the Olivaceous and the Narrow-billed Woodcreeper using conventional staining with Giemsa and silver nitrate staining of the nucleolar organizer regions (Ag-NORs). Metaphases were obtained by fibular bone marrow culture. The chromosome number of the Olivaceous Woodcreeper was 2n = 82 and of the Narrow-billed Woodcreeper, 2n = 82. Ag-NORs in the largest macrochromosome pair and evidence of a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cytogenetics; Woodcreepers; Ag-NOR; Chromosomal inversion.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000100010

The distribution of 45S rDNA sites in bird chromosomes suggests multiple evolutionary histories
Provedor de dados: 74
Autores: Degrandi,Tiago Marafiga; Gunski,Ricardo José; Garnero,Analía del Valle; Oliveira,Edivaldo Herculano Correa de; Kretschmer,Rafael; Souza,Marcelo Santos de; Barcellos,Suziane Alves; Hass,Iris.
Abstract The distribution of 45S rDNA cluster in avian karyotypes varies in different aspects, such as position, number of bearer chromosomes, and bearers being macro- or microchromosomes. The present study investigated the patterns of variation in the 45S rDNA-bearer chromosomes of birds in order to understand the evolutionary dynamics of the cluster configuration and its contribution to the evolution of bird karyotypes. A total of 73 bird species were analyzed, including both published data and species for which rDNA-FISH was conducted for the first time. In most birds, the 45S rDNA clusters were located in a single pair of microchromosomes. Hence, the location of 45S rDNA in macrochromosomes, observed only in Neognathae species, seems to be a derived...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: FISH; Chromosome; Chromosome evolution; Cytogenetics; Aves.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572020000400601

Novel insights into chromosome evolution of Charadriiformes: extensive genomic reshuffling in the wattled jacana (Jacana jacana, Charadriiformes, Jacanidae)
Provedor de dados: 74
Autores: Kretschmer,Rafael; Souza,Marcelo Santos de; Barcellos,Suziane Alves; Degrandi,Tiago Marafiga; Pereira,Jorge C.; O’Brien,Patricia C.M.; Ferguson-Smith,Malcolm A.; Gunski,Ricardo José; Garnero,Analía del Valle; Oliveira,Edivaldo Herculano Correa de; Freitas,Thales Renato Ochotorena de.
Abstract The order Charadriiformes comprises three major clades: Lari and Scolopaci as sister group to Charadrii. Until now, only three Charadriiformes species have been studied by chromosome painting: Larus argentatus (Lari), Burhinus oedicnemus and Vanellus chilensis (Charadrii). Hence, there is a lack of information concerning the third clade, Scolapaci. Based on this, and to gain a better understanding of karyotype evolution in the order Charadriiformes, we applied conventional and molecular cytogenetic approaches in a species belonging to clade Scolopaci - the wattled jacana (Jacana jacana) - using Gallus gallus and Zenaida auriculata chromosome-specific probes. Cross-species evaluation of J. jacana chromosomes shows extensive genomic reshuffling...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Charadrii; Karyotype; Avian genome; Comparative mapping.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572020000100601

Genetic trends in the expected progeny difference of the asymptotic weight of Nelore females
Provedor de dados: 74
Autores: Garnero,Analía del Valle; Marcondes,Cintia Righetti; Gunski,Ricardo José; Oliveira,Henrique Nunes de; Lôbo,Raysildo Barbosa.
There are few studies on weight covering the full life cycle of Zebu cattle, and there is no entire growth description or mean growth pattern for animals belonging to this breed. In order to provide such data, 1,158 Nelore females born between 1985 and 1995 were weighed 14,563 times from birth to full growth maturity, in ten herds spread over seven Brazilian states. The Von Bertalanffy, Brody, logistic and Gompertz non-linear models were used to obtain the asymptotic weights (A) and the maturation rates (K). The (co)variance and breeding value components for A and K were obtained by using the multiple trait derivative free restricted maximum likelihood method under the animal model. Genetic trends were calculated in function of the mean expected progeny...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adult weight; Bovine(s); Genetic trends; Maturation rate; Simulation with growth curves.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000400012

Abordagem bayesiana multivariada para características de crescimento, fertilidade e escores visuais de rebanhos da raça Brangus
Provedor de dados: 86
Autores: Araújo,Ronyere Olegário de; Marcondes,Cintia Righetti; Everling,Dionéia Magda; Weber,Tomás; Lopes,Jader Silva; Garnero,Analía del Valle; Gunski,Ricardo José; Rorato,Paulo Roberto Nogara.
O objetivo deste trabalho foi estimar parâmetros genéticos e tendências genéticas e fenotípicas de uma população da raça Brangus. As características peso, circunferência escrotal e escores visuais de conformação, precocidade, musculatura e umbigo, padronizadas para 550 dias de idade, foram avaliadas a partir de 6.789 registros de animais nascidos de 288 touros e 5.949 vacas, entre 1991 e 2001, em 49 fazendas localizadas nas regiões Centro‑Oeste, Sudeste e Sul do Brasil. Para a estimação dos parâmetros, das correlações e das tendências genéticas, foi adotado o modelo animal linear‑limiar hexacaracterística. As estimativas de herdabilidade direta foram de 0,39 e 0,27, para peso e circunferência escrotal, respectivamente, e de 0,22, 0,20, 0,23 e 0,33 para...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amostragem de Gibbs; Características morfológicas; Modelo de limiar; Precocidade de acabamento.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012000800007

Variabilidade genética do peso ao nascer e seleção para crescimento em bubalinos do Estado do Pará, Brasil
Provedor de dados: 36
Autores: Aguiari,Juliana Flor de; Marcondes,Cintia Righetti; Marques,José Ribamar Felipe; Vozzi,Pedro Alejandro; Camargo Júnior,Raimundo Nonato Colares; Marques,Larissa Coelho; Araújo,Ronyere Olegário; Gunski,Ricardo José.
O peso ao nascer constitui característica produtiva de elevada importância zootécnica, devido à sua relação com a taxa de sobrevivência à desmama e com os pesos nas demais fases de desenvolvimento do animal, quer seja para a produção de carne, leite ou em animais que se destinam à reprodução. O objetivo deste trabalho foi obter estimativas de herdabilidade e tendências fenotípicas e genéticas do peso ao nascer, em bubalinos do Estado do Pará, Brasil. Foram calculadas as estatísticas descritivas e realizado o teste de Normalidade de Shapiro-Wilk por meio do pacote estatístico Statistical Analisys System. As estimativas de herdabilidade foram obtidas por inferência Bayesiana. O peso ao nascer apresentou média de 36,6 kg. O modelo de análise considerou como...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Herdabilidade; Inferência Bayesiana; Tendência.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672014000300010

Classical nonlinear models to describe the growth curve for Murrah buffalo breed
Provedor de dados: 65
Autores: Araújo,Ronyere Olegário de; Marcondes,Cintia Righetti; Damé,Maria Cecília Florisbal; Garnero,Analía del Valle; Gunski,Ricardo José; Everling,Dionéia Magda; Rorato,Paulo Roberto Nogara.
With the objective of to adjust nonlinear models for the growth curves for a buffaloes herd raised in floodable lands in Rio Grande do Sul state, monthly records measured from birth to two years-old of 64 males and 63 females born between 1982 and 1989 were used. The models used were: Von Bertalanffy, Brody, Gompertz and Logistic. The parameters were estimated by NLIN procedure and the criteria used to evaluate the adjustment given by the models were: asymptotic standard deviation; coefficient of determination; average absolute deviation of residues and asymptotic index. Von Bertalanffy and Brody models overestimated the male asymptotic weight (A) in 15.9 and 171.3kg, respectively, and the Gompertz and Logistic models underestimated it in 4.5 and 13.4kg,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Asymptotic weight; Buffalo; Maturation rate.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782012000300022

Estimativas de parâmetros genéticos para características incluídas em critérios de seleção em gado Nelore
Provedor de dados: 65
Autores: Gunski,Ricardo José; Garnero,Analía del Valle; Borjas,Arcadio de los Reyes; Bezerra,Luiz Antônio Framartino; Lôbo,Raysildo Barbosa.
Foram analisados registros de 20 rebanhos integrantes do Programa de Melhoramento Genético da Raça Nelore (PMGRN), estudando-se as seguintes variáveis: ganho de peso por dia de idade até os 120, 200, 310 e 350kg (GPDpesok), peso padrão aos 120, 240, 365 e 550 dias de idade e peso real às idades mencionadas. As análises unicaráter mediante Modelo Animal, usando o aplicativo MTDFREML, proporcionaram estimativas de herdabilidades semelhantes para os pesos pré-desmama, variando entre 0,21-0,27 para o efeito direto, sendo que a correlação genética entre efeitos diretos e maternos foi negativa, variando entre -0,42 a -0,24. Para os pesos pós-desmama os coeficientes de herdabilidade foram maiores para as variáveis pesos padrão e peso real do que em relação ao...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Nelore; Modelo animal; Parâmetros genéticos; Critérios de seleção.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782001000400007