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1.
Neuroradiology ; 65(5): 915-922, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36750496

RESUMO

PURPOSE: The anatomical proximity of the styloid process (SP) to the ipsilateral internal carotid artery (ICA) has been recently recognized as a possible risk factor for carotid artery dissection (CAD). We aimed to verify this hypothesis by comparing the minimum distance between SP and ICA in young adult patients (< 55 years) with and without CAD. METHODS: Thirty-one CAD patients (cases) were compared with 41 sex-matched patients without dissection, group one of control (G1), and with 16 sex-matched patients with vertebral artery dissection (VAD), group two of control (G2). Two independent observers measured, on CT angiography images, the minimum distance on the axial plane between the SP and ICA in cases and controls. They evaluated both the intercentric and the marginal distance. Differences between groups were estimated by Student t-test. RESULTS: SP-ICA intercentric distance ipsilateral to dissection was significantly shorter compared to that of the contralateral side of cases (p < 0.001), to those of left and right side of G1 patients (p < 0.001 for both), and to those of left and right side of G2 patients (p < 0.001 for both). SP-ICA marginal distance of cases was significantly shorter compared to those of left and right side of G1 patients (p < 0.001 for both) and to those of left and right side of G2 patients (p < 0.001 for both). CONCLUSION: A short SP-ICA distance appears to be a risk factor for CAD as it likely induces a continuous microtraumatism of the vessel wall during normal head and neck movements.


Assuntos
Dissecação da Artéria Carótida Interna , Artéria Carótida Interna , Adulto Jovem , Humanos , Estudos de Casos e Controles , Artéria Carótida Interna/diagnóstico por imagem , Dissecação da Artéria Carótida Interna/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Fatores de Risco
2.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 827-835, May-June, 2020. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1129486

RESUMO

O colágeno é sintetizado e segregado no espaço extracelular e organizados em fibrilas estriadas de acordo com o tipo de tecido. Utilizaram-se 24 coelhos brancos da raça Nova Zelândia, com idade de 12 meses e com 3,0kg de peso corporal, para avaliar a porcentagem de colágeno das feridas cutâneas tratadas com plasma rico em plaquetas de equino e pomada contendo gentamicina, sulfanilamida, sulfadiazina, ureia e vitamina A. Os animais foram separados em quatro grupos de igual número e submetidos à remoção de pele na região das linhas médias dorsal torácica (feridas tratadas) e lombar (feridas controle). As feridas torácicas foram tratadas com plasma rico em plaqueta de equino e pomada contendo gentamicina, sulfanilamida, sulfadiazina, ureia e vitamina A, e as do grupo controle somente com a pomada. Dos animais do grupo I, foi coletado tecido cutâneo, para a avaliação histológica e a ultraestrutural, com três dias de pós-operatório; dos animais do grupo II, com sete dias; do grupo III, com 14 dias; e do grupo IV, com 21 dias. Decorrido o período de avaliação de cada grupo, foi coletado fragmento de pele para avaliação da porcentagem de colágeno, bem como do diâmetro e da densidade da fibrila de colágeno por microscopia eletrônica de transmissão. O tratamento com PRP de equino associado à aplicação tópica da pomada mostrou-se eficaz na maturação das fibrilas colágenas e na antecipação do processo cicatricial.(AU)


Collagen is synthesized and secreted into the extracellular space and organized into striated fibrils according to the tissue type. This study evaluated the concentration of collagen in rabbit skin wounds treated with equine platelet-rich plasma (PRP) and ointment containing gentamicin, sulfanilamide, sulfadiazine, urea, and vitamin A. Twenty-four New Zealand white rabbits aged 2 to 12 months and weighing 3.0kg were included. The animals were allocated equally into four groups and the skin was removed from the thoracic dorsal midline (treated wound) and lumbar (control wound) regions. The thoracic wounds were treated with equine PRP and ointment containing gentamicin, sulfanilamide, sulfadiazine, urea, and vitamin A, and the control group was treated with the ointment alone. For histological and ultrastructural assessment, cutaneous tissue was collected on postoperative days 3 (group I), 7 (group II), 14 (group III), and 21 (group IV). After the evaluation period, in each group, a skin fragment was collected for analysis of the collagen concentration, as well as the collagen fibril diameter and density by transmission electron microscopy. The results indicated that treatment with equine PRP combined with topical application of the ointment was effective in facilitating the maturation of collagen fibrils and the wound healing process.(AU)


Assuntos
Animais , Coelhos , Cicatrização/fisiologia , Ferimentos e Lesões/reabilitação , Ferimentos e Lesões/veterinária , Colágeno/ultraestrutura , Plasma Rico em Plaquetas , Sulfadiazina/administração & dosagem , Sulfanilamidas/administração & dosagem , Ureia/administração & dosagem , Vitamina A/administração & dosagem , Gentamicinas/administração & dosagem , Cavalos
3.
Clin Chim Acta ; 489: 242-248, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30153452

RESUMO

BACKGROUND: Metabolomics can be used to identify novel metabolites related to renal function and that could therefore be used for estimating GFR. We evaluated metabolites replicated and related to eGFR in 3 studies (CKD and general population). METHODS: Metabolomics was performed by GC-MS. The Progredir Cohort (n = 454, class 3 and 4 CKD) was used as the derivation study and adjusted linear regression models on eGFR-CKDEPI were built. Bonferroni correction was applied for selecting metabolites to be independently validated in the Diabetic Nephropathy Study (n = 56, macroalbuminuric DN) and in the Baependi Heart Study (BHS, n = 1145, general population). RESULTS: In the Progredir Cohort, 72 metabolites where associated with eGFR. Of those, 11 were also significantly associated to eGFR in the DN Study and 8 in the BHS. Four metabolites were replicated and significantly associated to eGFR in all 3 studies: d-threitol, myo-inositol, 4-deoxierythronic acid and galacturonic acid. In addition, pseudouridine was strongly correlated to eGFR only in the 2 CKD populations. CONCLUSIONS: Our results demonstrate metabolites that are potential biomarkers of renal function: d-threitol, myo-inositol, 4-deoxierythronic acid, galacturonic acid and pseudouridine. Further investigation is needed to determine their performance against otherwise gold-standard methods, most notably among those with normal eGFR.


Assuntos
Taxa de Filtração Glomerular , Metabolômica , Insuficiência Renal Crônica/metabolismo , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/fisiopatologia
4.
J Anim Breed Genet ; 134(1): 27-33, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27905150

RESUMO

The aim of this study was to estimate genetic parameters for prenatal (PRE) and postnatal (POS) mortality in Nellore cattle. A total of 13 141 (PRE) and 17 818 (POS) records from Nellore females were used. PRE and POS were recorded using binary scale scores: a score of '1' was given to calves that were born alive (PRE) and those that were alive at weaning (POS), and a score of '0' was given to calves that were not alive at or around birth (PRE), as well as to those weighed at birth but not at weaning (POS). The relationship matrix included 698 sires, 107 paternal grandsires and 69 maternal grandsires. Data were analysed using Bayesian inference and a sire-maternal grandsire threshold model, including contemporary groups as random effects, and the classes of dam age at the beginning of mating season (for PRE), and dam age at calving and birthweight (linear covariable) (for POS), as fixed effects. For both traits, the covariance between direct and maternal effects (rD,M ) was estimated (rD,M ≠ 0) or fixed at zero (rD,M  = 0). PRE and POS rates were 3.00 and 4.04%, respectively. Estimates of direct and maternal heritability were 0.07 and 0.17, respectively, for PRE, and 0.02 and 0.07, respectively, for POS, assuming rD,M  = 0. For rD,M  ≠ 0, these estimates were 0.07 and 0.12, respectively, for PRE, and 0.03 and 0.07, respectively, for POS. The correlation estimates between direct and maternal effects were -0.71 (PRE) and -0.33 (POS). PRE and POS show low genetic variability, indicating that these traits probably suffer major environmental influences. Additionally, our study shows that the maternal genetic component affects preweaning calf mortality twice as much (or more) as the direct genetic component. A large number of offspring per sire is necessary in progeny tests to genetically decrease calf mortality.


Assuntos
Bovinos/genética , Bovinos/fisiologia , Animais , Animais Recém-Nascidos , Bovinos/classificação , Feminino , Mortalidade , Gravidez
5.
Genet Mol Res ; 15(2)2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27173184

RESUMO

The study of genes associated with host defense mechanisms, such as the A2M gene, plays a critical role in preventing diseases that reduce milk yield and its constituents. The aim of this study was to identify polymorphisms in the A2M gene in Murrah buffaloes (Bubalus bubalis), and investigate their associations with milk yield, fat and protein production, fat and protein percentages, and somatic cell count. Hair follicle samples of 136 animals were collected for DNA extraction, and polymorphisms were identified by polymerase chain reactions and sequencing. Statistical analyses were performed to ascertain the allelic and genotypic frequencies, the Hardy-Weinberg equilibrium, and association analysis was conducted between the polymorphisms and the traits studied. Comparative analysis between buffalo and bovine sequences revealed seven nucleotide substitutions. Alignments among the buffalo sequences identified three single nucleotide polymorphisms (SNPs), including one in exon 29, g.241A>G, which was used in subsequent statistical analyses. A Hardy-Weinberg test indicated that this SNP was in equilibrium in this population, and was significantly associated (P < 0.05) with fat production and fat and protein percentages. Therefore, this SNP can be used as a molecular marker for these traits.


Assuntos
Búfalos/genética , Leite/metabolismo , Polimorfismo de Nucleotídeo Único , alfa-Macroglobulinas/genética , Animais , Feminino , Qualidade dos Alimentos , Lactação/genética , Masculino , Leite/normas
7.
Poult Sci ; 94(12): 2863-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26476088

RESUMO

This study investigates the genetic association of the SNP present in the ACTA1 gene with performance traits, organs and carcass of broilers to help marker-assisted selection of a paternal broiler line (TT) from EMBRAPA Swine and Poultry, Brazil. Genetic and phenotypic data of 1,400 broilers for 68 traits related to body performance, organ weights, weight of carcass parts, and yields as a percentage of organs and carcass parts were used. The maximum likelihood method, considering 4 analytical models, was used to analyze the genetic association between the SNP and these important economic traits. The association analysis was performed using a mixed animal model including the random effect of the animal (polygenic), and the fixed effects of sex (2 levels), hatch (5 levels) and SNP (3 levels), besides the random error. The traits significantly associated (P<0.05) with the SNP were analyzed, along with body weight at 42 days of age (BW42), by the restricted maximum likelihood method using the multi-trait animal model to estimate genetic parameters. The analysis included the residual and additive genetic random effects and the sex-hatch fixed effect. The additive effects of the SNP were associated with breast meat (BMY), liver yield (LIVY), body weight at 35 days of age (BW35); drumstick skin (DSW), drumstick (DW) and breast (BW) weights. The heritability estimates for these traits, in addition to BW42, ranged from 0.24±0.06 to 0.45±0.08 for LIVY and BW35, respectively. The genetic correlation ranged from 0.02±0.18 for LIVY and BMY to 0.97±0.01 for BW35 and BW42. Based on the results of this study, it can be concluded that ACTA1 gene is associated with performance traits BW35, LIV and BMY, DW, BW and DW adjusted for body weight at 42 days of age. Therefore, the ACTA1 gene is an important molecular marker that could be used together with others already described to increase the economically important traits in broilers.


Assuntos
Actinas/genética , Proteínas Aviárias/genética , Galinhas/fisiologia , Polimorfismo de Nucleotídeo Único , Actinas/metabolismo , Animais , Proteínas Aviárias/metabolismo , Peso Corporal , Brasil , Galinhas/genética , Galinhas/crescimento & desenvolvimento , Feminino , Marcadores Genéticos , Funções Verossimilhança , Masculino , Carne/análise , Tamanho do Órgão
8.
Genet Mol Res ; 14(3): 11133-44, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26400344

RESUMO

The objective of this study was to evaluate associations between single nucleotide polymorphism (SNP) markers and carcass traits measured postmortem in Nellore cattle. Records of loin eye area (LEA) and backfat thickness (BF) from 740 males and records of hot carcass weight (HCW) from 726 males were analyzed. All of the animals were genotyped using the BovineHD BeadChip. Association analyses were performed by the restricted maximum likelihood method that considered one SNP at a time. Significant SNPs were identified on chromosomes 2 and 6 for LEA and on chromosomes 7, 1, and 2 for BF. For HCW, associations with SNPs were found on chromosomes 13, 14, and 28, in addition to genome regions that were directly related to this trait, such as the EFCAB8 and VSTM2L genes, and to bone development (RHOU). Some SNPs were located in very close proximity to genes involved in basal metabolism (BLCAP, NNAT, CTNNBL1, TGM2, and LOC100296770) and the immune system (BPI).


Assuntos
Carne/normas , Animais , Peso Corporal/genética , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Qualidade dos Alimentos , Frequência do Gene , Marcadores Genéticos , Estudo de Associação Genômica Ampla , Genótipo , Masculino , Músculo Esquelético/fisiologia , Polimorfismo de Nucleotídeo Único , Gordura Subcutânea/anatomia & histologia
9.
Genet Mol Res ; 14(2): 7151-62, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26125926

RESUMO

The objective of this study was to quantify the magnitude of genotype-environment interaction (GxE) effects on age at first calving (AFC), scrotal circumference (SC), and yearling weight (YW) in Nellore cattle using reaction norms. For the study, 89,152 weight records of female and male Nellore animals obtained at yearling age were used. Genetic parameters were estimated with a single-trait random-regression model using Legendre polynomials as base functions. The heritability estimates were of low to medium magnitude for AFC (0.05 to 0.47) and of medium to high magnitude for SC (0.32 to 0.51) and YW (0.13 to 0.72), and increased as the environmental gradient became more favorable. The genetic correlation estimates ranged from 0.25 to 1.0 for AFC, from 0.71 to 1.0 for SC, and from 0.42 to 1.0 for YW. High Spearman correlation coefficients were obtained for the three traits, ranging from 0.97 to 0.99. The reaction norms along the environmental gradient of 10 sires each with the highest or lowest breeding value for YW predicted by single-trait analysis demonstrated more plastic phenotypes for YW and more robust phenotypes for SC. The effect of GxE was most important for YW and AFC with respect to SC. When animals are selected for higher SC or YW or lower AFC, considering or not the GxE effect, it is expected that the same animals will be selected. The reaction norms obtained based on sire breeding values along the environmental gradient showed that animals with extreme breeding values respond differently as environmental conditions improve.


Assuntos
Interação Gene-Ambiente , Genótipo , Fenótipo , Característica Quantitativa Herdável , Maturidade Sexual/genética , Fatores Etários , Criação de Animais Domésticos , Animais , Peso Corporal , Cruzamento , Bovinos , Feminino , Masculino , Modelos Genéticos , Escroto/anatomia & histologia , Escroto/fisiologia
10.
J Anim Sci ; 93(4): 1503-10, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26020172

RESUMO

The aim of this study was to evaluate the effect of genotype × environment interaction (G×E) on age at first calving (AFC), scrotal circumference (SC), and yearling weight (YW) and to estimate genetic correlations between these traits in Nellore cattle using reaction norms in multitrait random regression models. In this study, 28,871, 41,386, and 89,152 records of Nellore cattle for AFC, SC, and YW, respectively, were used. The data were obtained from farms located in the north, northeast, midwest, and southeast regions of Brazil that participate in the DeltaGen Breeding Program. Environmental levels were defined as a function of contemporary groups, that is, animals born in the same herd and year, from the same management group (from birth to yearling), and of the same sex. Postweaning weight gain was used as a criterion to evaluate the environmental conditions for all traits. For reaction norm analyses, residual variances were modeled with homogeneous and heterogeneous classes. The model for SC and YW included the fixed effects of contemporary group and age of the animal as a covariate as well as random direct additive genetic and residual effects. The same model, excluding the covariate age of the animal, was used for AFC. The heritability estimates were low to high for AFC (0.09 to 0.50), high for SC (0.51 to 0.67), and moderate to high for YW (0.33 to 0.71). The genetic correlations (within each trait) along the environmental levels varied from -0.27 to 1.0 for AFC, from 0.73 to 1.0 for SC, and from 0.26 to 1.0 for YW. The genetic correlations between different traits in different environments varied from -0.14 to -0.60 between AFC and SC, from -0.05 to -0.32 between AFC and YW, and from -0.05 to 0.72 between YW and SC. The genetic correlations have had different magnitudes for AFC, SC, and YW, which could indicate the presence of G×E. The present results should support researchers and farmers in defining selection criteria to improve growth traits and sexual precocity. Our results suggest that animals for breeding have to be selected in the same environment and management conditions as their progeny will be reared.


Assuntos
Peso Corporal/fisiologia , Cruzamento/métodos , Bovinos/genética , Meio Ambiente , Genótipo , Modelos Genéticos , Escroto/crescimento & desenvolvimento , Fatores Etários , Animais , Peso Corporal/genética , Brasil , Cruzamento/normas , Bovinos/crescimento & desenvolvimento , Feminino , Masculino , Análise de Regressão
11.
Genet Mol Res ; 14(4): 18713-9, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26782521

RESUMO

The aim of this study was to estimate genetic and phenotypic associations of growth traits with carcass and meat traits in Nellore cattle. Data from male and female animals were used for weaning weight (WW; N = 241,416), yearling weight (YW, N = 126,596), weight gain from weaning to yearling (GWY, N = 78,687), and yearling hip height (YHH, N = 90,720), respectively; 877 male animals were used for hot carcass weight (HCW) and 884 for longissimus muscle area (LMA), backfat thickness (BT), marbling score (MS), and shear force (SF). The variance components were estimated by the restricted maximum likelihood method using three-trait animal models that included WW. The model for WW included direct and maternal additive genetic, maternal permanent environmental, and residual effects as random effects; contemporary group as fixed effects; and age of dam at calving and age of animal as covariates (linear and quadratic effects). For the other traits, maternal effects and the effect of age of dam at calving were excluded from the model. Heritability ranged from 0.10 ± 0.12 (LMA) to 0.44 ± 0.007 (YW). Genetic correlations ranged from -0.40 ± 0.38 (WW x LMA) to 0.55 ± 0.10 (HCW x YW). Growth, carcass, and meat traits have sufficient genetic variability to be included as selection criteria in animal breeding programs.


Assuntos
Estudos de Associação Genética , Característica Quantitativa Herdável , Carne Vermelha , Animais , Bovinos , Feminino , Masculino , Fenótipo
12.
Genet Mol Res ; 13(4): 10256-68, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25501237

RESUMO

The aim of this study was to identify single-nucleotide polymorphisms (SNPs) in buffaloes associated with milk yield and content, in addition to somatic cell scores based on the cross-species transferability of SNPs from cattle to buffalo. A total of 15,745 SNPs were analyzed, of which 1562 showed 1% significance and 4742 with 5% significance, which were associated for all traits studied. After application of Bonferroni's correction for multiple tests of the traits analyzed, we found 2 significant SNPs placed on cattle chromosomes BTA15 and BTA20, which are homologous to buffalo chromosomes BBU16 and BBU19, respectively. In this genome association study, we found several significant SNPs affecting buffalo milk production and quality. Furthermore, the use of the high-density bovine BeadChip was suitable for genomic analysis in buffaloes. Although extensive chromosome arm homology was described between cattle and buffalo, the exact chromosomal position of SNP markers associated with these economically important traits in buffalo can be determined only through buffalo genome sequencing.


Assuntos
Búfalos/genética , Estudo de Associação Genômica Ampla/veterinária , Lactação , Polimorfismo de Nucleotídeo Único , Animais , Bovinos , Cromossomos de Mamíferos , Feminino , Marcadores Genéticos , Genótipo , Locos de Características Quantitativas
13.
Genet Mol Res ; 13(4): 10294-300, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25501241

RESUMO

The objective of this study was to estimate the genetic and environmental parameters for carcass, carcass part, and organ weights in a paternal strain of broiler chickens that was selected mainly for body weight at 42 days of age (BW42) to provide support for poultry genetic improvement programs. A total of 1448 chickens were used that resulted from the expansion of a pure paternal strain named TT, which was developed by Embrapa Suínos e Aves. The following weights were evaluated: BW42, chilled carcass, wing, drumstick meat, thigh meat, breast meat, breast fillet, back, liver, heart (HRT), and gizzard (GIZ). The variance component was estimated by the restricted maximum likelihood method using a multi-trait animal model. The general model included the additive genetic and residual random effects and the fixed effect of the sex-hatch group (10 levels). The heritability estimates ranged from 0.27 ± 0.06 for HRT to 0.44 ± 0.08 for GIZ. These results indicated that all the traits have enough additive genetic variability to respond to selection. The genetic correlation estimates between BW42 and the carcass and carcass part weights were high and positive. However, the genetic correlation estimates between BW42 and organ weights were low. In this population, the carcass traits might respond indirectly to selection applied to BW42. It can be concluded that selection to increase BW42 is not effective in improving broiler organ weight. Therefore, to obtain suitable genetic improvement for these traits, the selection indexes for broilers should include organ weight-based criteria.


Assuntos
Galinhas/genética , Fenótipo , Característica Quantitativa Herdável , Animais , Peso Corporal , Cruzamento , Galinhas/classificação , Feminino , Humanos , Funções Verossimilhança , Carne
14.
Ann Ig ; 26(5): 435-42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25405374

RESUMO

BACKGROUND: In recent years, the nursing licensure exam is at the centre of a national and international wide debate. This debate regards the planning of the nursing licensure exam in many Universities and the competences that this exam must certify to ensure quality, effectiveness, and ethics of nursing care from newly-graduated nurses to general public. The aim of this study was to describe the practical tests used for the licensure exam in the four Universities of the Lazio Region. The researchers analyzed the type of practical tests used and the field of competences assessed according to the degrees of performance defined by the Dublin Descriptors. METHODS: The data were collected through semi-structured interviews to Presidents, Directors and Lecturers of nursing degree courses and through direct retrieval of the written texts of the licensure exam. Two researchers analyzed the practical tests. A special lecture-grid divided into three different sections to interpret the data was created. Statistical analysis was carried out by means of Epi-info 3.5.1/2008. RESULTS: Analysis of data showed that the most used tests were Discussion of theoretical and practical aspects in context (33.6%), followed by the Test with open and/or closed questions (23,9%). Psychomotor and relational skills tests were little used. The most valued field of competence was the cognitive one (85,5%) that assessed, above all, the storage of the concept. The ability to interpret data and solve problems was less valued. CONCLUSIONS: The study showed the high discrepancy in the types of tests used in the four Universities of the Lazio Region. Universities found it difficult to assess psychomotor and relational skills of the students. Most of the cognitive tests utilized omitted the evaluation of mastery of complex competences. Therefore, there is the necessity of a new planning of the nursing licensure exam to overcome these critical issues.


Assuntos
Educação em Enfermagem , Avaliação Educacional/métodos , Licenciamento em Enfermagem , Competência Clínica , Educação Baseada em Competências , Estudos Transversais , Currículo , Coleta de Dados , Humanos , Itália , Universidades
15.
Br Poult Sci ; 55(6): 728-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25269694

RESUMO

1. objective of the present study was to estimate heritability for hatch weight (HW), body weight at 90 (W90) and 180 (W180) d of age in Brazilian ostriches. 2. The heritability estimates were obtained through the restricted maximum likelihood method for an animal model. Least squares method was used to define possible fixed effects for consideration in the analysis model. 3. The estimates of heritability were 0.42 ± 0.05, 0.16 ± 0.04 and 0.24 ± 0.08 for HW, W90 and W180, respectively. 4. Heritability estimates showed that there are sufficient levels of additive genetic variation present in the traits studied, and these traits may respond to selection.


Assuntos
Peso Corporal/genética , Struthioniformes/anatomia & histologia , Animais , Hibridização Genética , Masculino , Fenótipo , Característica Quantitativa Herdável , Struthioniformes/genética
16.
Poult Sci ; 92(9): 2283-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23960110

RESUMO

The objectives of this study were to estimate genetic parameters for accumulated egg production over 3-wk periods and for total egg production over 54 wk of egg-laying, and using principal component analysis (PCA), to explore the relationships among the breeding values of these traits to identify the possible genetic relationships present among them and hence to observe which of them could be used as selection criteria for improving egg production. Egg production was measured among 1,512 females of a line of White Leghorn laying hens. The traits analyzed were the number of eggs produced over partial periods of 3 wk, thus totaling 18 partial periods (P1 to P18), and the total number of eggs produced over the period between the 17 and 70 wk of age (PTOT), thus totaling 54 wk of egg production. Estimates of genetic parameters were obtained by means of the restricted maximum likelihood method, using 2-trait animal models. The PCA was done using the breeding values of partial and total egg production. The heritability estimates ranged from 0.05 ± 0.03 (P1 and P8) to 0.27 ± 0.06 (P4) in the 2-trait analysis. The genetic correlations between PTOT and partial periods ranged from 0.19 ± 0.31 (P1) to 1.00 ± 0.05 (P10, P11, and P12). Despite the high genetic correlation, selection of birds based on P10, P11, and P12 did not result in an increase in PTOT because of the low heritability estimates for these periods (0.06 ± 0.03, 0.12 ± 0.04, and 0.10 ± 0.04, respectively). The PCA showed that egg production can be divided genetically into 4 periods, and that P1 and P2 are independent and have little genetic association with the other periods.


Assuntos
Criação de Animais Domésticos , Galinhas/fisiologia , Ovos , Reprodução , Seleção Genética , Animais , Brasil , Cruzamento , Galinhas/genética , Feminino , Funções Verossimilhança , Fenótipo , Análise de Componente Principal , Estações do Ano , Fatores de Tempo
17.
Reprod Fertil Dev ; 25(5): 775-81, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22953973

RESUMO

Phenotypic data from female Canchim beef cattle were used to obtain estimates of genetic parameters for reproduction and growth traits using a linear animal mixed model. In addition, relationships among animal estimated breeding values (EBVs) for these traits were explored using principal component analysis. The traits studied in female Canchim cattle were age at first calving (AFC), age at second calving (ASC), calving interval (CI), and bodyweight at 420 days of age (BW420). The heritability estimates for AFC, ASC, CI and BW420 were 0.03±0.01, 0.07±0.01, 0.06±0.02, and 0.24±0.02, respectively. The genetic correlations for AFC with ASC, AFC with CI, AFC with BW420, ASC with CI, ASC with BW420, and CI with BW420 were 0.87±0.07, 0.23±0.02, -0.15±0.01, 0.67±0.13, -0.07±0.13, and 0.02±0.14, respectively. Standardised EBVs for AFC, ASC and CI exhibited a high association with the first principal component, whereas the standardised EBV for BW420 was closely associated with the second principal component. The heritability estimates for AFC, ASC and CI suggest that these traits would respond slowly to selection. However, selection response could be enhanced by constructing selection indices based on the principal components.


Assuntos
Cruzamento/normas , Bovinos/genética , Bovinos/fisiologia , Crescimento e Desenvolvimento/fisiologia , Fenótipo , Reprodução/fisiologia , Fatores Etários , Animais , Peso Corporal , Brasil , Feminino , Crescimento e Desenvolvimento/genética , Modelos Lineares , Análise de Componente Principal , Reprodução/genética
18.
Genet Mol Res ; 11(3): 1819-29, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22869538

RESUMO

We estimated genetic parameters for egg production in different periods by means of random regression models, aiming at selection based on partial egg production from a generation of layers. The production was evaluated for each individual by recording the number of eggs produced from 20 to 70 weeks of age, with partial records taken every three weeks for a total of 17 periods. The covariance functions were estimated with a random regression model by the restricted maximum likelihood method. A model composed of third-order polynomials for the additive effect, ninth-order polynomials for the permanent environment, and a residual variance structure with five distinct classes, was found to be most suitable for adjusting the egg production data for laying hens. The heritability estimates varied from 0.04 to 0.14. The genetic correlations were all positive, varying from 0.10 to 0.99. Selection applied in partial egg production periods will result in greater genetic profit for the adjacent periods. However, as the distance in time between periods increases, selection becomes less efficient. Selection based on the second period (23 to 25 weeks of age), where greater heritability was estimated, would note benefit the final egg-laying cycle periods.


Assuntos
Galinhas/genética , Modelos Genéticos , Oviposição/genética , Envelhecimento/genética , Animais , Padrões de Herança/genética , Funções Verossimilhança , Fenótipo , Análise de Regressão
19.
Meat Sci ; 91(3): 352-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22405874

RESUMO

In this study, the objective was to estimate genetic parameters of body weight at 210 (BW210) and 365 (BW365) days of age in relation to rib eye area (REA), subcutaneous back fat thickness (BF) and rump fat (RF), and their respective genetic trends, in Nelore beef cattle. Estimates of genetic parameters and breeding values for the studied traits were obtained using the REML method. The direct and maternal heritability estimates were respectively: 0.25±0.02 and 0.21±0.01, for BW210, and 0.29±0.02 and 0.09±0.01, for BW365. The heritability estimates for transformed REA, BF and RF were 0.29±0.03, 0.21±0.02 and 0.23±0.03, respectively. There were genetic associations between BW210 and REA, BW365 and REA, and BF and RF, while the other correlations were low. The selection process that was conducted at the farms participating in the breeding program, taking the proposed selection index into consideration, caused genetic changes to these traits.


Assuntos
Tecido Adiposo/metabolismo , Peso Corporal/genética , Cruzamento/métodos , Bovinos/genética , Gorduras na Dieta/análise , Carne/análise , Característica Quantitativa Herdável , Animais , Bovinos/crescimento & desenvolvimento
20.
Artigo em Inglês | MEDLINE | ID: mdl-22255329

RESUMO

We present a system to keep track of a destructive process such as a medical specimen dissection, from data acquisition to interactive and immersive visualization, in order to build ground truth models. Acquisition is a two-step process, first involving a 3D laser scanner to get a 3D surface, and then a high resolution camera for capturing the texture. This acquisition process is repeated at each step of the dissection, depending on the expected accuracy and the specific objects to be studied. Thanks to fiducial markers, surfaces are registered on each others. Experts can then explore data using interaction hardware in an immersive 3D visualization. An interactive labeling tool is provided to the anatomist, in order to identify regions of interest on each acquired surface. 3D objects can then be reconstructed according to the selected surfaces. We aim to produce ground truths which for instance can be used to validate data acquired with MRI. The system is applied to the specific case of white fibers reconstruction in the human brain.


Assuntos
Manejo de Espécimes , Imageamento Tridimensional , Propriedades de Superfície
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