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1.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 961-969, May-June, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1129665

RESUMO

A total of 6593 weight records collected from 796 male and female Anglo-Nubian goats aged up to 130 days, offspring from 29 sires and 225 dams, were used to compare models and estimate genetic parameters throughout the growth curve by applying random regression models. Direct and maternal additive genetic effects and direct and maternal permanent environmental effects were included as random in the models. The contemporary groups were included as fixed effects and goat age at kidding was included as a covariable (linear and quadratic). The choice of the best model was based on the AIC, BIC and AICc criteria. Variance estimates of the four random effects increased as the animals aged. Direct heritability (h2) rose from 0.13 to 0.40 with age, whereas maternal heritability showed a low value. Genetic correlations of weight between closer ages were high. The most suitable random regression model to compare the fitting of random effects was that which employed the Legendre polynomials of quadratic order with homogeneous variance (3333-1).(AU)


Utilizaram-se 6593 pesos de 796 caprinos da raça Anglonubiana, coletados em machos e fêmeas com idade até 130 dias, descendentes de 29 reprodutores e 225 matrizes, com o objetivo de se compararem modelos e de se estimarem parâmetros genéticos ao longo da curva de crescimento com aplicação de modelos de regressão aleatória. Nos modelos, incluíram-se os efeitos genéticos aditivos diretos e maternos e os de ambiente permanente diretos e maternos como aleatórios; os grupos de contemporâneos foram incluídos como efeitos fixos, e a idade da cabra ao parto como covariável (linear e quadrática). A escolha do melhor modelo foi realizada pela avaliação dos critérios AIC, BIC e AICc. As estimativas de variâncias dos quatro efeitos aleatórios cresceram de acordo com o aumento da idade. A herdabilidade direta (h2) aumentou de 0,13 a 0,40 com a idade, e a materna apresentou baixo valor. As correlações genéticas do peso entre idades mais próximas foram altas. O modelo de regressão aleatório mais adequado ao se comparar o ajuste dos efeitos aleatórios foi o que empregou polinômios de Legendre de ordem quadrática com variância homogênea (3333-1).(AU)


Assuntos
Animais , Ruminantes/crescimento & desenvolvimento , Análise de Regressão , Perfil Genético , Hereditariedade , Correlação de Dados
2.
Genet Mol Res ; 15(4)2016 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-27966746

RESUMO

Brazil is the world's largest producer of beef cattle; however, the quality of its herds needs to be improved. The use of molecular markers as auxiliary tools in selecting animals for reproduction with high pattern for beef production would significantly improve the quality of the final beef product in Brazil. The leptin gene has been demonstrated to be an excellent candidate gene for bovine breeding. The objective of this study was to sequence and compare the leptin gene promoter of Brazil's important cattle breeds in order to identify polymorphisms in it. Blood samples of the Nellore, Guzerat, Tabapuã, and Senepol breeds were collected for genomic DNA extraction. The genomic DNA was used as a template for polymerase chain reaction (PCR) to amplify a 1575-bp fragment, which in turn was sequenced, aligned, and compared between animals of different breeds. Twenty-three single nucleotide polymorphic sites, including transitions and transversions, were detected at positions -1457, -1452, -1446, -1397, -1392, -1361, -1238, -963,-901, -578, -516, -483, -478, -470, -432, -430, -292, -282, -272, -211, -202, -170, and -147. Additionally, two insertion sites at positions -680 and -416 and two deletion sites at positions -1255 and -1059 were detected. As the promoter region of the leptin gene has been demonstrated to vary among breeds, these variations must be tested for their use as potential molecular markers for artificial selection of animals for enhanced beef production in different systems of bovine production in Brazil.


Assuntos
Leptina/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Análise de Sequência de DNA/métodos , Animais , Brasil , Cruzamento , Bovinos , Frequência do Gene , Marcadores Genéticos , Carne Vermelha
3.
Genet Mol Res ; 14(4): 12805-10, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26505431

RESUMO

The northern region of Brazil produces a large number of sheep, with Pará being the largest sheep breeding state in the region. In the Amazon region, livestock production is a challenge due to the high diversity of pathogens affecting humans and animals. Defensins are antimicrobial peptides acting as a first barrier against micro-organisms and present high variation in different organisms. The objective of this study was to detect polymorphisms in exon II in ß-defensin II in Amazon sheep. The gene was amplified by PCR from DNA extracted from 47 sheep blood samples from the Santa Inês breed. Products were sequenced, aligned and analyzed. Three single nucleotide polymorphism (SNP) positions were observed with transition substitutions (A↔G) at positions 1643, 1659, and 1750. The 1643 and 1750 SNPs showed a low variability and significant deviations from Hardy-Weinberg equilibrium (HWE) (P < 0.05) meanwhile the SNP 1659 showed moderate absence of genetic variability and deviation from HWE (P > 0.05). Polymorphisms at 1643 and 1659 were predicted to modify amino acids in the peptide chain (isoleucine to valine and arginine to lysine, respectively) with no effects on protein function. Results from this study suggest that SNPs are important markers for ß-defensin II efficiency studies on the immune system of sheep in the Brazilian Amazon.


Assuntos
Polimorfismo de Nucleotídeo Único/genética , beta-Defensinas/genética , Animais , Brasil , Feminino , Imunidade Inata/genética , Imunidade Inata/fisiologia , Masculino , Ovinos
5.
Genet Mol Res ; 13(1): 2149-54, 2014 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-24737439

RESUMO

Curraleiro Pé-Duro is a rustic bovine taurine breed found in Northeast of Brazil; this breed has decreased its production potentially in order to adapt to the region environment conditions. Consequently, it is under risk of extinction and is maintained at a preservation center in Piauí State, Brazil, as a source of genetic material adapted to local conditions. We analyzed genetic variability of this breed using microsatellite markers. Sixty animals were genotyped using 11 microsatellite loci normally used for paternity tests in bovines. The observed number of alleles ranged from 5 to 9, and the effective number of alleles ranged from 2.01 to 4.64. The Shannon index ranged from 0.949 to 1.669. The expected heterozygosity ranged from 0.510 to 0.798. Polymorphism information content values ranged from 0.453 to 0.751. Divergence from Hardy-Weinberg equilibrium was significant and the mean FIS value was 0.010. We conclude that this breed still has some genetic diversity, but with evident risk due to genetic drift caused by current breeding management. It will be necessary to insert animals from other herds to obtain the desired level of genetic variability in this breed remnant.


Assuntos
Cruzamento , Variação Genética , Repetições de Microssatélites , Alelos , Animais , Brasil , Bovinos , Loci Gênicos , Genótipo
6.
Arq. bras. med. vet. zootec ; 65(3): 885-893, June 2013. tab
Artigo em Português | LILACS | ID: lil-679126

RESUMO

Foram estimados os componentes de variância e os parâmetros genéticos da característica prolificidade, utilizando-se inferência bayesiana sob modelo animal linear e de limiar. A prolificidade de cabras mestiças foi estudada com informações referentes ao período de oito anos consecutivos. As análises foram realizadas com cadeias de 500.000 ciclos. Considerou-se burn-in dos 15.000 valores iniciais, sendo tomados valores a cada 250 ciclos, para se obter a distribuição a posteriori com 1.940 amostras. Os efeitos do mês de cobrição e da ordem de parto e o efeito linear do peso à cobrição foram significativos. As herdabilidades foram de 0,03 e 0,18 para o modelo linear e o modelo de limiar, respectivamente. O uso do modelo de limiar mostrou-se adequado, produzindo estimativas superiores acerca dos parâmetros estimados.


Variance components and genetic parameters of the litter size trait, using Bayesian inference under linear and threshold animal model were estimated. The litter size of crossbred goats was studied with information regarding a period of eight consecutive years. Analyses were performed with 500,000 cycle chains. The burn-in of the 15,000 baseline values was considered and these were taken every 250 cycles to obtain a posteriori distribution with 1,940 effective samples. Statistical analyses showed that the effects of coverage month, delivery order and linear effect of weight on coverage were significant. The heritabilities were 0.03 and 0.18 for linear and threshold models respectively. The threshold model proved to be suitable, producing higher estimates regarding the estimated parameters.


Assuntos
Animais , Estatísticas Ambientais/estatística & dados numéricos , Genética/instrumentação , Cabras/classificação
7.
Actas esp. psiquiatr ; 32(2): 123-126, mar. 2004.
Artigo em Es | IBECS | ID: ibc-32248

RESUMO

A partir de la descripción de un caso clínico visto por los autores, con diagnóstico de trastorno disociativo, se realiza una revisión del tema de estos trastornos y de las polémicas que lo acompañan. Se presta atención a los conceptos de disociación e histeria, su evolución histórica y sus relaciones. Se mencionan también algunas teorías explicativas actuales desde el modelo cognitivo y su posible relación u oposición con las teorías psicodinámicas, resaltando la diferencia, desde estos distintos enfoques, entre disociación y represión. En las conclusiones se señala que en el campo de lo disociativo hay todavía problemas importantes a los que enfrentarse para avanzar en el conocimiento psiquiátrico de este grupo de trastornos (AU)


No disponible


Assuntos
Masculino , Humanos , Adulto , Transtornos Dissociativos , Repressão Psicológica , Índice de Gravidade de Doença
8.
Arq. bras. med. vet. zootec ; 55(6): 685-693, dez. 2003. ilus, tab
Artigo em Português | LILACS | ID: lil-359831

RESUMO

Verificou-se a influência da heterogeneidade de variâncias na avaliação genética de bovinos de corte da raça Tabapuã. Dados de pesos corrigidos aos 120, 240 e 420 dias de idade foram estratificados com base no desvio-padrão fenotípico do peso aos 120 dias dos grupos de contemporâneos em três classes: baixo (<14,9kg), médio (14,9 a 18,9kg) e alto (>18,9kg) desvio-padrão. Nas análises de múltiplas características, em que o peso foi considerado característica distinta em cada classe de desvio-padrão, constatou-se que as variâncias genéticas e residuais foram maiores com o aumento do desvio-padrão da classe. As herdabilidades foram 0,26, 0,32 e 0,37 (peso aos 120 dias), 0,28, 0,35 e 0,35 (peso aos 240 dias) e 0,14, 0,18 e 0,18 (peso aos 420 dias) nas classes de baixo, médio e alto desvio-padrão, respectivamente. As correlações genéticas entre o mesmo peso, nas classes de baixo e alto desvio-padrão foram inferiores a 0,80. As correlações entre os valores genéticos, obtidos de análises múltiplas e de análise geral (sem as classes), foram superiores a 0,93. Observou-se que os reprodutores seriam classificados de forma similar se for considerada ou não a presença de variâncias heterogêneas nas análises


Assuntos
Bovinos , Heterogeneidade Genética
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 67(6 Pt 2): 066111, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16241308

RESUMO

We study distributions of dissipative and nondissipative avalanches in Manna's stochastic sandpile, in one and two dimensions. Our results lead to the following conclusions: (1) avalanche distributions, in general, do not follow simple power laws, but rather have the form P(s) approximately s(-tau(s))(ln s)(gamma)f(s/s(c)), with f a cutoff function; (2) the exponents for sizes of dissipative avalanches in two dimensions differ markedly from the corresponding values for the Bak-Tang-Wiesenfeld (BTW) model, implying that the BTW and Manna models belong to distinct universality classes; (3) dissipative avalanche distributions obey finite-size scaling, unlike in the BTW model.

10.
J Pediatr (Rio J) ; 77(5): 374-80, 2001.
Artigo em Português | MEDLINE | ID: mdl-14647841

RESUMO

OBJECTIVES: Evaluate physiological and behavioral parameters to verify if newborns feel pain when submitted to gastric suctioning. METHODS: 50 healthy newborns over 33 weeks gestational age, weighing more than 1999g, were submitted to gastric suctioning, randomly selected, and divided into two groups: Friction/Lancing and Lancing/Friction. The newborns were assessed through the Neonatal Infant Pain Scale (NIPS) (0-7, pain>3) by two independent observers in three different moments: one minute before, during, and one minute after gastric suctioning, heel lancing and foot friction, with simultaneous monitoring of heart rate, respiratory frequency, and hemoglobin oxygen saturation. RESULTS: The respiratory frequency only decreased during gastric suctioning (P=0.004). The heart rate was lower during gastric suctioning (P<0.0001), during the heel lacing procedure in the Friction/Lancing group (P=0.01), and during friction in the Friction/Lancing group (P=0.022). The hemoglobin oxygen saturation suffered no alterations during the three procedures. The results obtained through NIPS revealed that both groups felt pain during gastric suctioning and heel lancing, and did not feel pain during friction (P<0.0001). CONCLUSION: During the gastric suctioning procedure, newborns responded as if it were a painful stimulus. Physiological alterations were neither specific nor sensitive to pain assessment in newborn infants.

11.
Amino Acids ; 2(1-2): 87-95, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24194275

RESUMO

A preparative-scale enantioselective hydrolysis of racemic methyl esters of several N-protected amino acid has been carried out by using crude porcine pancreatic lipase (Triacylglycerol lipase, EC 3.1.1.3) PPL as a hydrolytic enzyme. In all cases 50% of the racemic methyl ester was hydrolysed to the N-protected L-amino acid with high yield and high optical purity.Hydrolysis rates were very close related not only to the amino acid structure but also to the steric and/or electronic nature of the ester and N-protecting groups. Thus, the very convenient ester methyl group can be enantioselectively hydrolysed with PPL when N-protecting group is a carbonyl derivative, as it is the usual benzoyl group.

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