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The objective of this study was to evaluate the effects of amino resin-treated soybean meal (SBM) on ruminal fermentation, nutrient digestion, and N partitioning. The treatments were (1) untreated solvent-extracted SBM, (2) amino resin-treated SBM (AR-SBM), and (3) heat-treated SBM (HT-SBM). The experimental design was arranged as a replicated 3 × 3 Latin square with 6 fermentors in a dual-flow continuous culture system. Treatments were randomly assigned to fermentors within a Latin square for each period. Each fermentor was fed 106 g/d of diet DM equally distributed in 2 feeding times daily at 0800 and 1800 h. Diets were formulated to contain 16% CP, 30% NDF, and 30% starch across treatments. The experiment consisted of 3 experimental periods, each lasting for 10 d. The first 7 d of each period were considered adaptation, and the last 3 d were used for sampling and data collection. On d 8 and 9, samples were collected for analysis of diurnal variation in concentrations of NH3-N, pH, and VFA during the first 8 h after feeding. On d 8, 9, and 10, samples were collected from the liquid and solid effluents accumulated over 24 h for analysis of daily averages of NH3-N and VFA pools, and true ruminal digestibility estimates. Data were analyzed using the MIXED procedure of SAS, and significance was declared when P ≤ 0.05. The model included the fixed effect of treatment and random effects of square, period, and fermentor within square, whereas time and interaction treatment × time were included for analyses of diurnal variation, with time as repeated measures. Compared with SBM, the cultured ruminal contents of AR-SBM and HT-SBM had lower NH3-N concentrations, indicating lower microbial fermentation of protein. Molar proportions of isovalerate and isobutyrate were greater in SBM than AR-SBM and HT-SBM, with greater molar proportion of isobutyrate for SBM, particularly during the first 2 h after feeding. The flow of NH3-N was greater for SBM compared with AR-SBM and HT-SBM, whereas NAN flow, bacterial N flow, and N efficiency were greater for AR-SBM and HT-SBM compared with SBM. Our results indicate that both the amino resin and heat treatments of SBM allow for similar decreases in microbial degradation of CP without limiting microbial protein synthesis in diets with 16% CP. Amino resin treatment may be effective in reducing microbial fermentation of protein in the rumen without adverse effects on digestibility or fermentation parameters as compared with SBM.

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Several methods have been used for genome-enabled prediction (or genomic selection) of complex traits, for example, multiple regression models describing a target trait with a linear function of a set of genetic markers. Genomic selection studies have been focused mostly on single-trait analyses. However, most profitability traits are genetically correlated, and an increase in prediction accuracy of genomic breeding values for genetically correlated traits is expected when using multiple-trait models. Thus, this study was carried out to assess the accuracy of genomic prediction for carcass and meat quality traits in Nelore cattle, using single- and multiple-trait approaches. The study considered 15 780, 15 784, 15 742 and 526 records of rib eye area (REA, cm2), back fat thickness (BF, mm), rump fat (RF, mm) and Warner-Bratzler shear force (WBSF, kg), respectively, in Nelore cattle, from the Nelore Brazil Breeding Program. Animals were genotyped with a low-density single nucleotide polymorphism (SNP) panel and subsequently imputed to arrays with 54 and 777 k SNPs. Four Bayesian specifications of genomic regression models, namely, Bayes A, Bayes B, Bayes Cπ and Bayesian Ridge Regression; blending methods, BLUP; and single-step genomic best linear unbiased prediction (ssGBLUP) methods were compared in terms of prediction accuracy using a fivefold cross-validation. Estimates of heritability ranged from 0.20 to 0.35 and from 0.21 to 0.46 for RF and WBSF on single- and multiple-trait analyses, respectively. Prediction accuracies for REA, BF, RF and WBSF were all similar using the different specifications of regression models. In addition, this study has shown the impact of genomic information upon genetic evaluations in beef cattle using the multiple-trait model, which was also advantageous compared to the single-trait model because it accounted for the selection process using multiple traits at the same time. The advantage of multi-trait analyses is attributed to the consideration of correlations and genetic influences between the traits, in addition to the non-random association of alleles.

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The absence of formal markets and the large variability of genetic groups and production systems of goats and sheep in developing countries hinder the implementation of traditional breeding programmes. Community-based breeding programmes (CBBP) for these species have been shown to be effective in these countries. In these programmes, the definition of the objectives and criteria of selection is done in a participatory way, which takes into account the desires and needs of the local farmers. We aimed to define the objectives and criteria of a CBBP for goats and sheep in the Inhamuns region, Ceará, Brazil, using a participatory rural appraisal (PRA). This methodology, which consist in an approach that aims to incorporate the knowledge and opinions of rural people in the planning and management of development projects and programmes, was performed in seven districts of two towns of the region (Tauá and Parambu). One hundred twenty-two farmer families participated in the survey. The PRA was able to provide important information, and its results showed that breeders of this region keep flocks of goats and sheep for social, economic and cultural benefits. In order of importance, the main objectives for goat farming were personal fulfilment (PERF), food source for family (FSF), income generation (INCG), savings (SAV) and cultural/family traditions (CULT), while for sheep farming were CULT, FSF, SAV, PERF and INCG. Disease resistance (RDI), adaptability (ADP), fertility (FERT), growth rate (GRA), host resistance of worms (HRW), body conformation (BC), temperament (TEM), longevity (LONG), body size (BSIZ), age at first kidding (AFK) and milk yield (MIY) were the main selection criteria that farmers use for goats. The most important selection criteria used for selecting sheep were ADP, RDI, HRW, GRA, FERT, LONG, BC, BS and age at first lambing. According to these objectives and criteria, the CBBP must consider the adaptation of the animals to the climate and management conditions of the region, the resistance to diseases and productive performance.

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Utilizaram-se registros de pesos corporais padronizados aos 120, 210, 365 e 450 dias de idade, provenientes de 30.481 animais da raça Nelore, progênies de 211 reprodutores acasalados com 19.229 matrizes, oriundos de rebanhos dos estados de Mato Grosso, Mato Grosso do Sul e Goiás, com o objetivo de avaliar a presença de interação genótipo x ambiente entre os estados. As estimativas de herdabilidade entre os estados variaram de 0,09 a 0,14; 0,11 a 0,17; 0,16 a 0,27 e 0,17 a 0,35, respectivamente, para os pesos 120, 210, 365 e 450 dias de idade. As estimativas de correlação genética aditiva entre a mesma característica para os diferentes estados apresentaram valores inferiores a 0,80. As correlações de Spearman entre os valores genéticos para os pesos corporais se reduziram à medida que se aumentou a intensidade de seleção sobre os reprodutores. A presença de interação genótipo x ambiente causa maior impacto sobre a avaliação genética dos reprodutores sob intensidade de seleção elevada, sendo interessante sua consideração no processo de avaliação genética. Estimativas de tendências genéticas para todos os pesos corporais apresentaram-se crescentes ao longo dos anos nos três estados.(AU)

Data of adjusted alive weights at 120, 210, 365 and 450 days of age of 30,481 records of animals of the Nellore beef cattle breed from herds of states of Mato Grosso, Mato Grosso do Sul, and Goiás were used to study the influence of environment genotype interaction on genetic evaluation of sires. Estimates of heritability between the states ranged from 0.09 to 0.14; 0.11 to 0.17; 0.16 to 0.27 and 0.17 to 0.35, respectively for live weights 120, 210, 365 and 450 days of age. The estimates of additive genetic correlation between the same characteristic for the different states presented values lower than 0.80. Spearman correlations between breeding values obtained from live weights of sires lowered as the intensity of selection on sires increased. The presence of environment genotype interaction has greater impact on the genetic evaluation of breeding under high intensity of selection, being an interesting consideration in the process of genetic evaluation. Estimates of genetic trends for all body weights have been increasing over the years in all three states.(AU)

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Utilizaram-se registros de pesos corporais padronizados aos 120, 210, 365 e 450 dias de idade, provenientes de 30.481 animais da raça Nelore, progênies de 211 reprodutores acasalados com 19.229 matrizes, oriundos de rebanhos dos estados de Mato Grosso, Mato Grosso do Sul e Goiás, com o objetivo de avaliar a presença de interação genótipo x ambiente entre os estados. As estimativas de herdabilidade entre os estados variaram de 0,09 a 0,14; 0,11 a 0,17; 0,16 a 0,27 e 0,17 a 0,35, respectivamente, para os pesos 120, 210, 365 e 450 dias de idade. As estimativas de correlação genética aditiva entre a mesma característica para os diferentes estados apresentaram valores inferiores a 0,80. As correlações de Spearman entre os valores genéticos para os pesos corporais se reduziram à medida que se aumentou a intensidade de seleção sobre os reprodutores. A presença de interação genótipo x ambiente causa maior impacto sobre a avaliação genética dos reprodutores sob intensidade de seleção elevada, sendo interessante sua consideração no processo de avaliação genética. Estimativas de tendências genéticas para todos os pesos corporais apresentaram-se crescentes ao longo dos anos nos três estados.(AU)

Data of adjusted alive weights at 120, 210, 365 and 450 days of age of 30,481 records of animals of the Nellore beef cattle breed from herds of states of Mato Grosso, Mato Grosso do Sul, and Goiás were used to study the influence of environment genotype interaction on genetic evaluation of sires. Estimates of heritability between the states ranged from 0.09 to 0.14; 0.11 to 0.17; 0.16 to 0.27 and 0.17 to 0.35, respectively for live weights 120, 210, 365 and 450 days of age. The estimates of additive genetic correlation between the same characteristic for the different states presented values lower than 0.80. Spearman correlations between breeding values obtained from live weights of sires lowered as the intensity of selection on sires increased. The presence of environment genotype interaction has greater impact on the genetic evaluation of breeding under high intensity of selection, being an interesting consideration in the process of genetic evaluation. Estimates of genetic trends for all body weights have been increasing over the years in all three states.(AU)

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BACKGROUND: There have been few studies exploring implementation strategies to central line-associated bloodstream infections (CLABSIs) in low- or middle-income countries. AIM: To implement tailored interventions to reduce CLABSI rates in adult intensive care units. METHODS: The implementation strategy of the State Health Department was performed in São Paulo State, Brazil, over two cycles. Cycle 1 (56 hospitals) was exploratory and cycle 2 (77 hospitals) was designed to confirm the hypothesis generated by the first cycle, with three phases each (pre-intervention, intervention, post-intervention). Cycles included: evaluation of healthcare workers' knowledge, observation of practices, and CLABSI rates monthly report. In cycle 1, a log-normal mixed model was used to select variables significantly associated with the reduction of CLABSI. In cycle 2, CLABSI rates were evaluated. FINDINGS: Healthcare workers' practices improved after intervention. In cycle 1, reduction of CLABSI rates was more pronounced in hospitals with initial CLABSI rates >7.4 per 1000 catheter-days (P < 0.001) and those that introduced the use of peripherally inserted central catheters (P = 0.01). For hospitals with high CLABSI initial rates, simulation demonstrated that the rates were expected to decrease by 36% (95% CI: 9-63), no matter the type of intervention. In cycle 2, there was an overall decrease in CLABSI rates during the intervention period; whereas the mean rate fell further post-intervention, rates at the 90th percentile increased. CONCLUSION: The implementation strategy may have had an effect on infection rates independently of the specific interventions implemented; however, the sustainability of reduction in the post-intervention period remains a challenge.

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The female reproductive performance, productivity and size are strongly associated with production efficiency of herds raised in a tropical environment. The age at first calving (AFC), accumulated productivity (AP), stayability (STAY) and mature weight (MW) could be used as indicators of these traits. In this study, the genetic parameters and correlations between AFC, AP, STAY and MW measured in Nellore females were estimated, in order to provide support for the beef cattle evaluation programs. In addition, the genetic changes for these traits were obtained. The (co)variance components were estimated by Gibbs sampling by four-trait multivariate analysis, using a threshold animal model for STAY and linear animal model for the other traits (AFC, AP and MW). Heritability of AFC, AP and STAY showed low values, with posterior means of 0.13 ± 0.02, 0.14 ± 0.01 and 0.19 ± 0.03, respectively. On the other hand, for MW were estimated mean heritability of 0.44 ± 0.03 and repeatability of 0.77 ± 0.03, demonstrating the importance of genetic and permanent environmental effects for the expression of beef cows' size. The AFC showed null genetic correlation with AP (-0.06 ± 0.12) and MW (0.01 ± 0.09) and low and negative with STAY (-0.15 ± 0.11). The AP showed high genetic correlation with STAY (0.86 ± 0.03) and weak with MW (0.23 ± 0.09). Positive and moderate genetic association was estimated between STAY and MW (0.66 ± 0.05). Annual direct genetic trends of 0.19 kg, 0.30 units and 0.10 kg were estimated for AP, STAY and MW, respectively, and were significant (P < 0.05) for STAY and MW. For AFC, negative and favorable annual genetic change was estimated (-0.08 months, P < 0.05). In this population, the selection of heifers for an early reproductive age should have little influence, however favorable, in the time that the cows remain in the herd. The use of AP as a selection criterion should result in smaller changes in the females' mature weight when compared to selection based on STAY.

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We assessed whether single nucleotide polymorphisms (SNPs) in the genes beta 1,4- galactosyltransferase (B4GALT1), luteinizing hormone receptor (LHR), follicle-stimulating hormone receptor (FSHR) and insulin-like growth factor 2 (IGF2) could be molecular markers for scrotal circumference (SC) in Nellore bulls. Animals with positive (+, n = 104) and negative (-, n = 74) expected progeny difference for scrotal circumference at 365 days (EPD SC 365) were selected and their SNPs were analyzed by restriction fragment length polymorphism (RFLP). The correlation between EPD SC 365 and expected progeny difference for age at first birth (EPD AFB) was also investigated. The SNPs in B4GALT1 and FSHR was not different between two groups analyzed. The CC genotype for LHR gene was most frequent in animals with EPD SC 365(+), whereas the TT was most frequent in the EPD SC 365(-). For IGF2 the CT and CC were the most frequent genotypes observed in animals with positive and negative EPD SC 365, respectively. The EPD SC 365 was negatively correlated with the EPD AFB (r = 0.23). We suggest that CC and TT genotypes for LHR and IGF2, respectively, could be possible molecular markers for SC selection in Nellore bulls, that can also predict for AFB.(AU)

Foram avaliados se polimorfismos de base única (SNPs) presentes nos genes beta-1,4- galactosiltransferase (B4GALT1), receptor de hormônio luteinizante (LHR), receptor de hormônio folículo estimulante (FSHR) e fator de crescimento semelhante à insulina 2 (IGF2) poderiam ser marcadores moleculares para o perímetro escrotal (PE) em touros da raça Nelore. Animais com diferença esperada de progênie positiva (+, n = 104) e negativa (-, n = 74) para PE aos 365 dias (DEP PE 365) foram selecionados e seus SNPs foram analisados utilizando a técnica de polimorfismo de comprimento de fragmentos de restrição (RFLP). A correlação entre DEP PE 365 e idade ao primeiro parto (DEP IPP) também foi investigada. Os SNPs dos genes B4GALT1 e FSHR não apresentaram diferença entre os dois grupos analisados. O genótipo CC para o gene LHR foi mais freqüente em animais com DEP PE 365 (+), enquanto o TT foi mais frequente no grupo com DEP PE 365 (-). Para o gene IGF2, os genótipos CT e CC foram mais freqüentes em animais com DEP PE 365 positiva e negativa, respectivamente. A DEP PE 365 foi negativamente correlacionada com a DEP IPP (r = -0,23). O genótipo CC para o gene LHR e genótipo TT para o gene IGF2 podem ser possíveis marcadores de PE para a seleção assistida em touros da raça Nelore, podendo ser ainda preditores para IPP.(AU)

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We assessed whether single nucleotide polymorphisms (SNPs) in the genes beta 1,4- galactosyltransferase (B4GALT1), luteinizing hormone receptor (LHR), follicle-stimulating hormone receptor (FSHR) and insulin-like growth factor 2 (IGF2) could be molecular markers for scrotal circumference (SC) in Nellore bulls. Animals with positive (+, n = 104) and negative (-, n = 74) expected progeny difference for scrotal circumference at 365 days (EPD SC 365) were selected and their SNPs were analyzed by restriction fragment length polymorphism (RFLP). The correlation between EPD SC 365 and expected progeny difference for age at first birth (EPD AFB) was also investigated. The SNPs in B4GALT1 and FSHR was not different between two groups analyzed. The CC genotype for LHR gene was most frequent in animals with EPD SC 365(+), whereas the TT was most frequent in the EPD SC 365(-). For IGF2 the CT and CC were the most frequent genotypes observed in animals with positive and negative EPD SC 365, respectively. The EPD SC 365 was negatively correlated with the EPD AFB (r = 0.23). We suggest that CC and TT genotypes for LHR and IGF2, respectively, could be possible molecular markers for SC selection in Nellore bulls, that can also predict for AFB.

Foram avaliados se polimorfismos de base única (SNPs) presentes nos genes beta-1,4- galactosiltransferase (B4GALT1), receptor de hormônio luteinizante (LHR), receptor de hormônio folículo estimulante (FSHR) e fator de crescimento semelhante à insulina 2 (IGF2) poderiam ser marcadores moleculares para o perímetro escrotal (PE) em touros da raça Nelore. Animais com diferença esperada de progênie positiva (+, n = 104) e negativa (-, n = 74) para PE aos 365 dias (DEP PE 365) foram selecionados e seus SNPs foram analisados utilizando a técnica de polimorfismo de comprimento de fragmentos de restrição (RFLP). A correlação entre DEP PE 365 e idade ao primeiro parto (DEP IPP) também foi investigada. Os SNPs dos genes B4GALT1 e FSHR não apresentaram diferença entre os dois grupos analisados. O genótipo CC para o gene LHR foi mais freqüente em animais com DEP PE 365 (+), enquanto o TT foi mais frequente no grupo com DEP PE 365 (-). Para o gene IGF2, os genótipos CT e CC foram mais freqüentes em animais com DEP PE 365 positiva e negativa, respectivamente. A DEP PE 365 foi negativamente correlacionada com a DEP IPP (r = -0,23). O genótipo CC para o gene LHR e genótipo TT para o gene IGF2 podem ser possíveis marcadores de PE para a seleção assistida em touros da raça Nelore, podendo ser ainda preditores para IPP.

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This study was carried out to investigate (co)variance components and genetic parameters for growth traits in beef cattle using a multi-trait model by Bayesian methods. Genetic and residual (co)variances and parameters were estimated for weights at standard ages of 120 (W120), 210 (W210), 365 (W365), and 450 days (W450), and for pre- and post-weaning daily weight gain (preWWG and postWWG) in Nellore cattle. Data were collected over 16 years (1993-2009), and all animals were raised on pasture in eight farms in the North of Brazil that participate in the National Association of Breeders and Researchers. Analyses were run by the Bayesian approach using Gibbs sampler. Additive direct heritabilities for W120, W210, W365, and W450 and for preWWG and postWWG were 0.28 ± 0.013, 0.32 ± 0.002, 0.31 ± 0.002, 0.50 ± 0.026, 0.61 ± 0.047, and 0.79 ± 0.055, respectively. The estimates of maternal heritability were 0.32 ± 0.012, 0.29 ± 0.004, 0.30 ± 0.005, 0.25 ± 0.015, 0.23 ± 0.017, and 0.22 ± 0.016, respectively, for W120, W210, W365, and W450 and for preWWG and postWWG. The estimates of genetic direct additive correlation among all traits were positive and ranged from 0.25 ± 0.03 (preWWG and postWWG) to 0.99 ± 0.00 (W210 and preWWG). The moderate to high estimates of heritability and genetic correlation for weights and daily weight gains at different ages is suggestive of genetic improvement in these traits by selection at an appropriate age. Maternal genetic effects seemed to be significant across the traits. When the focus is on direct and maternal effects, W210 seems to be a good criterium for the selection of Nellore cattle considering the importance of this breed as a major breed of beef cattle not only in Northern Brazil but all regions covered by tropical pastures. As in this study the genetic correlations among all traits were high, the selection based on weaning weight might be a good choice because at this age there are two important effects (maternal and direct genetic effects). In contrast, W120 should be preferred when the objective is improving the maternal ability of the dams. Furthermore, selection for postWWG can be used if the animals show both heavier weaning weights and high growth rate after weaning because it is possible to shorten the time between weaning and slaughter based on weaning weight, postWWG, and desired weight at the time of slaughter.

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Objetivou-se avaliar a influência da qualidade da informação na predição de valores genéticos para características de crescimento em bovinos da raça Nelore. Foram utilizadas informações de fazendas participantes do Programa Nelore Brasil da Associação Nacional de Criadores e Pesquisadores, considerando-se dados zootécnicos obtidos entre 2012 e 2013. Foram analisadas as características de crescimento relacionadas aos pesos aos 120 (P120), 210 (P210), 365 (P365) e 450 (P450) dias de idade, sob diferentes cenários: inclusão de todas as informações de lote de manejo (cenário de referência) e inclusão aleatória de 90%, 70%, 50%, 30% e 0% das informações de lote de manejo dos animais com medidas fenotípicas. Os valores genéticos foram preditos mediante análises unicaracterísticas sob modelo animal. Ocorreram alterações em todos os parâmetros genéticos quando comparados aos obtidos pelo cenário de referência. Houve um aumento nas estimativas de herdabilidade à medida que se reduziu o número de informações sobre os lotes de manejo. Esses resultados sugerem que o progresso genético estimado para rebanhos com baixa qualidade da informação zootécnica pode não expressar adequadamente o que realmente está ocorrendo com o rebanho, uma vez que as estimativas de herdabilidade podem estar infladas. Verificou-se que houve alteração na classificação dos animais para todas as características de crescimento avaliadas. A qualidade da informação zootécnica influencia na predição dos valores genéticos para as características de crescimento.(AU)

The objective was to evaluate the influence of information quality in the prediction of genetic values for the Nellore cattle's growth traits. The information came from cattle farms participating in the program of the Brazilian National Association of Breeders and Researchers (ANCP), from 2012 to 2013. Field data such as batch or management group were considered assessment criteria, and the growth traits related to body weight at 120 (W120), 210 (W210), 365 (W365) and 450 (W450) days under different scenarios: inclusion of all management lot information; and random inclusion of 90%, 70%, 50%, 30% and 0% of the batch management of information from animals with phenotypic measurements. Breeding values were predicted by using univariate models in animal model. Changes on all genetic parameters were compared to those obtained in the reference scenario. There was an increase in the estimates of heritability as it reduced the number of details about lots of management. These results suggest that gene progress estimated herds with low quality information do not adequately represent what truly occurs with the herd, since heritability estimates may be inflated. Change in the classification of animals was found at all the growth traits. The quality information influences the prediction of breeding values for growth traits.(AU)

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Objetivou-se avaliar a influência da qualidade da informação na predição de valores genéticos para características de crescimento em bovinos da raça Nelore. Foram utilizadas informações de fazendas participantes do Programa Nelore Brasil da Associação Nacional de Criadores e Pesquisadores, considerando-se dados zootécnicos obtidos entre 2012 e 2013. Foram analisadas as características de crescimento relacionadas aos pesos aos 120 (P120), 210 (P210), 365 (P365) e 450 (P450) dias de idade, sob diferentes cenários: inclusão de todas as informações de lote de manejo (cenário de referência) e inclusão aleatória de 90%, 70%, 50%, 30% e 0% das informações de lote de manejo dos animais com medidas fenotípicas. Os valores genéticos foram preditos mediante análises unicaracterísticas sob modelo animal. Ocorreram alterações em todos os parâmetros genéticos quando comparados aos obtidos pelo cenário de referência. Houve um aumento nas estimativas de herdabilidade à medida que se reduziu o número de informações sobre os lotes de manejo. Esses resultados sugerem que o progresso genético estimado para rebanhos com baixa qualidade da informação zootécnica pode não expressar adequadamente o que realmente está ocorrendo com o rebanho, uma vez que as estimativas de herdabilidade podem estar infladas. Verificou-se que houve alteração na classificação dos animais para todas as características de crescimento avaliadas. A qualidade da informação zootécnica influencia na predição dos valores genéticos para as características de crescimento.

The objective was to evaluate the influence of information quality in the prediction of genetic values for the Nellore cattle's growth traits. The information came from cattle farms participating in the program of the Brazilian National Association of Breeders and Researchers (ANCP), from 2012 to 2013. Field data such as batch or management group were considered assessment criteria, and the growth traits related to body weight at 120 (W120), 210 (W210), 365 (W365) and 450 (W450) days under different scenarios: inclusion of all management lot information; and random inclusion of 90%, 70%, 50%, 30% and 0% of the batch management of information from animals with phenotypic measurements. Breeding values were predicted by using univariate models in animal model. Changes on all genetic parameters were compared to those obtained in the reference scenario. There was an increase in the estimates of heritability as it reduced the number of details about lots of management. These results suggest that gene progress estimated herds with low quality information do not adequately represent what truly occurs with the herd, since heritability estimates may be inflated. Change in the classification of animals was found at all the growth traits. The quality information influences the prediction of breeding values for growth traits.

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The aim of this study was to estimate genetic parameters for scrotal circumference at 365 (SC365) and 450 (SC450) days of age, age at first calving (AFC), ribeye area (REA), backfat (BF) thickness, and rump fat (RF) thickness, in order to provide information on potential traits for Nelore cattle breeding program. Genetic parameters were estimated using the Average Information Restricted Maximum Likelihood method in single- and multitrait analyses. Four different animal models were tested for SC365, SC450, REA, BF, and RF in single-trait analyses. For SC365 and SC450, the maternal genetic effect was statistically significant (P < 0.01) and was included for multitrait analyses. The direct heritability estimates for SC365, SC450, AFC, REA, BF, and RF were equal to 0.31, 0.38, 0.24, 0.32, 0.16, and 0.19, respectively. Maternal heritability for SC365 and SC450 was equal to 0.06 and 0.08, respectively. The highest genetic correlations were found among the scrotal circumferences. Testing for the inclusion of maternal effects in genetic parameters estimation for scrotal circumference should be evaluated in the Nelore breeding program, mostly for correctly ranking the animal's estimated breeding values. Similar heritability estimates were observed for scrotal circumference, as well as favorable genetic correlations of this trait with AFC and carcass traits. Thus, scrotal circumference measured at 365 days of age could be a target trait for consideration in the Nelore selection index in order to improve most of the traits herein analyzed.

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The aims of our study were to estimate genetic parameters for body weight and visual scores and to evaluate their inclusion as selection criteria in the Nelore breeding program in Brazil. The traits studied were the body weight adjusted to 210 (W210) and to 450 (W450) days of age and visual scores for body structure, finishing precocity, and muscling evaluated at weaning (BSW, FPW, and MSW) and yearling (BSY, FPY, and MSY) ages. A total of 33,242, 26,259, 23,075, and 26,057 observations were considered to analyze W210, W450, and visual scores at weaning and yearling. The significant (P < 0.05) fixed effects for all traits were farm, birth season, birth year, sex, and management group. Single-trait analyses were performed to define the most fitting model to our data using the average information restricted maximum likelihood algorithm, for weaning traits. Subsequently, these models were used in single- and two-trait analyses considering the Bayesian inference algorithm. Two-trait Bayesian analyses resulted in average direct heritability estimates for BSW, FPW, MSW, W210, BSY, FPY, MSY, and W450 of 0.28, 0.30, 0.27, 0.28, 0.40, 0.44, 0.39, and 0.50, respectively. Genetic correlations varied from 0.40 to 0.96. Benefits to animal performance can best be achieved by considering body structure, finishing precocity, and muscling as selection criteria in the Nelore breeding programs. The decision to use visual scores measured at weaning should be considered in order to decrease generation interval and assist pre-selecting individuals, expecting carcass improvements in the future progeny.

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Polynomial functions of different orders were used to model random effects associated with weight of Santa Ines sheep from birth to 196 days. Fixed effects included in the models were contemporary groups, age of ewe at lambing, and fourth-order Legendre polynomials for age to represent the average growth curve. In the random part, functions of different orders were included to model variances associated with direct additive and maternal genetic effects and with permanent environmental effects of the animal and mother. Residual variance was fitted by a sixth-order ordinary polynomial for age. The higher the order of the functions, the better the model fit the data. According to the Akaike information criterion and likelihood ratio test, a continuous function of order, five, five, seven, and three for direct additive genetic, maternal genetic, animal permanent environmental, and maternal permanent environmental effects (k = 5573), respectively, was sufficient to model changes in (co)variances with age. However, a more parsimonious model of order three, three, five, and three (k = 3353) was suggested based on Schwarz's Bayesian information criterion for the same effects. Since it was a more flexible model, model k = 5573 provided inconsistent genetic parameter estimates when compared to the biologically expected result. Predicted breeding values obtained with models k = 3353 and k = 5573 differed, especially at young ages. Model k = 3353 adequately fit changes in variances and covariances with time, and may be used to describe changes in variances with age in the Santa Ines sheep studied.

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RESUMO

Foram utilizados 138.976 registros de informações de pesos corporais variando de 60 a 610 dias de idade, provenientes de 27.327 animais da raça Nelore, oriundos de rebanhos do estado do Mato Grosso, com o objetivo de descrever a variabilidade genética e estimar parâmetros genéticos para o peso corporal em diferentes idades, utilizando-se modelos de regressão aleatória. O modelo empregado incluiu efeitos fixos de grupo de contemporâneos e idade da vaca ao parto como covariáveis, além de efeitos aleatórios genético aditivo direto, genético materno, ambiente permanente de animal, ambiente permanente materno e efeito de ambiente temporário. O modelo de regressão aleatória mais adequado foi o que empregou função de covariância com polinômios de quarta ordem para descrição da variabilidade de todos os efeitos e duas classes de variância residual. As estimativas de variância genética aditiva direta e de ambiente permanente de animal aumentaram com a idade dos animais. As variâncias genética materna e de ambiente permanente materno exibiram comportamento semelhante, com maiores valores na fase de aleitamento. Os coeficientes de herdabilidade estimados variam de 0,25 a 0,43, com maiores valores nas idades mais avançadas na trajetória de crescimento dos animais. Esses resultados indicaram presença de variabilidade genética suficiente para obtenção de ganho genético expressivo por meio da seleção, principalmente após desmama. Os resultados encontrados para a correlação genética aditiva direta exibiram baixas correlações entre pesos nas idades iniciais e finais, porém pesos altamente correlacionados entre idades mais próximas. As correlações genéticas estimadas entre os pesos da desmama com os pesos até 610 dias de idade foram altas e positivas e indicam que os genes responsáveis por maiores pesos nesse período, em sua maioria, são os mesmos.

In this study 138,976 records of live weight between 60 to 610 days of age, from 27,327 Nellore cattle breed, from herds in Mato Grosso State were used in order to describe the genetic variability and to estimate genetic parameters for the live weight at different ages, using random regression models. The model included the fixed effects of contemporary group and age of cow at calving as covariate, random effects of direct additive genetic, maternal genetic, animal and maternal permanent environmental and temporary environment effect. The most appropriate random regression model employed the covariance function with fourth order polynomials to describe the variability of all effects and two residual variance classes. Estimates of direct additive genetic variance and animal permanent environment increased with the age of the animals. Maternal genetic variances and maternal permanent environment exhibited similar behavior, with higher values in pre weaning. The estimated heritability coefficients ranged from 0.25 to 0.43, with higher values at older ages in the growth trajectory of the animals. These results showed the presence of sufficient genetic variability to obtain significant genetic gain through selection, especially after weaning. The results for the direct additive genetic correlation exhibited low correlations between weights in initial and final ages, however, highly correlated weights between nearest ages. Genetic correlation estimates between weaning with weights up to 610 days of age were high and positive and indicate that most of the genes responsible for higher weights in this period are the same.

Assuntos

RESUMO

Foram utilizados 138.976 registros de informações de pesos corporais variando de 60 a 610 dias de idade, provenientes de 27.327 animais da raça Nelore, oriundos de rebanhos do estado do Mato Grosso, com o objetivo de descrever a variabilidade genética e estimar parâmetros genéticos para o peso corporal em diferentes idades, utilizando-se modelos de regressão aleatória. O modelo empregado incluiu efeitos fixos de grupo de contemporâneos e idade da vaca ao parto como covariáveis, além de efeitos aleatórios genético aditivo direto, genético materno, ambiente permanente de animal, ambiente permanente materno e efeito de ambiente temporário. O modelo de regressão aleatória mais adequado foi o que empregou função de covariância com polinômios de quarta ordem para descrição da variabilidade de todos os efeitos e duas classes de variância residual. As estimativas de variância genética aditiva direta e de ambiente permanente de animal aumentaram com a idade dos animais. As variâncias genética materna e de ambiente permanente materno exibiram comportamento semelhante, com maiores valores na fase de aleitamento. Os coeficientes de herdabilidade estimados variam de 0,25 a 0,43, com maiores valores nas idades mais avançadas na trajetória de crescimento dos animais. Esses resultados indicaram presença de variabilidade genética suficiente para obtenção de ganho genético expressivo por meio da seleção, principalmente após desmama. Os resultados encontrados para a correlação genética aditiva direta exibiram baixas correlações entre pesos nas idades iniciais e finais, porém pesos altamente correlacionados entre idades mais próximas. As correlações genéticas estimadas entre os pesos da desmama com os pesos até 610 dias de idade foram altas e positivas e indicam que os genes responsáveis por maiores pesos nesse período, em sua maioria, são os mesmos.(AU)

In this study 138,976 records of live weight between 60 to 610 days of age, from 27,327 Nellore cattle breed, from herds in Mato Grosso State were used in order to describe the genetic variability and to estimate genetic parameters for the live weight at different ages, using random regression models. The model included the fixed effects of contemporary group and age of cow at calving as covariate, random effects of direct additive genetic, maternal genetic, animal and maternal permanent environmental and temporary environment effect. The most appropriate random regression model employed the covariance function with fourth order polynomials to describe the variability of all effects and two residual variance classes. Estimates of direct additive genetic variance and animal permanent environment increased with the age of the animals. Maternal genetic variances and maternal permanent environment exhibited similar behavior, with higher values in pre weaning. The estimated heritability coefficients ranged from 0.25 to 0.43, with higher values at older ages in the growth trajectory of the animals. These results showed the presence of sufficient genetic variability to obtain significant genetic gain through selection, especially after weaning. The results for the direct additive genetic correlation exhibited low correlations between weights in initial and final ages, however, highly correlated weights between nearest ages. Genetic correlation estimates between weaning with weights up to 610 days of age were high and positive and indicate that most of the genes responsible for higher weights in this period are the same.(AU)

Assuntos

RESUMO

The aim of this study was to compare the following four genetic groups of hair sheep: Santa Inês (SI), Morada Nova (MN), Brazilian Somali (BS), and the F1 1/2Dorper x 1/2Morada Nova crossbreed on traits related to growth and parasitic infection. Thirty-three male lambs of the same age and of simple birth, under the same pre-weaning management conditions were used in the experiment. After weaning the animals were housed in a completely randomized design in paddocks made of Panicum maximum cv. Tanzania. Along the course of the research, the performance of the four groups of sheep was observed to be negatively affected by gastrointestinal parasites, but there was a genotype effect to the average daily weight gain (ADWG), where the SI and F1 genotypes presented higher values. The effects of genotype, time and genotype x time interaction were significant in weight and corporal score (CS) measurements. The BS lambs had the highest CS values throughout the experiment despite not presenting greater weight gain when compared to the SI and F1 breeds. There were also significant effects of time and genotype x time interaction for packed cell volume (PCV) and FAMACHA© score (FAM) and only the time effect was significant in the total number of eggs per gram (EPG) and total plasma protein (TPP). The MN lambs showed higher PCV values and unlike the other groups, presented a FAMACHA© score below 3 and PCV above 23% even having a higher EPG tendency, especially in the initial phase, indicating a possible higher resilience to infection caused by gastrointestinal parasites.

O objetivo deste estudo foi comparar quatro grupos genéticos de ovinos: Santa Inês (SI), Somalis Brasileira (SB), Morada Nova (MN) e 1/2 Dorper - 1/2 Morada Nova (F1) quanto às características de crescimento e de infecção parasitária. Trinta e três cordeiros machos, de mesma idade, nascidos de parto simples e submetidos às mesmas condições de manejo pré-desmame foram utilizados no experimento. Após o desmame, os animais foram alojados em piquetes de capim Panicum maximum cv. Tanzânia, em um sistema rotativo de pastejo sob um delineamento inteiramente ao acaso. Os resultados mostraram que, ao longo do experimento, o desempenho ponderal dos quatro grupos genéticos foi negativamente afetado pela infecção por endoparasitas, mas o efeito de genótipo foi significativo para ganho de peso médio diário, e os grupos SI e F1 apresentaram melhores médias. O efeito do genótipo, tempo e interação genótipo x tempo foi significativo para o peso e o escore corporal. Os cordeiros da raça SB apresentaram maiores escores corporais ao longo do experimento, apesar do menor ganho de peso quando comparados aos dos grupos SI e F1. Houve efeito significativo do tempo e da interação genótipo x tempo para o hematócrito e para o grau FAMACHA©. Somente efeito do tempo foi verificado para as características OPG e proteína plasmática total. Os cordeiros da raça Morada Nova, ao contrário dos demais grupos, mantiveram o grau FAMACHA© inferior a 3 e hematócrito inferior a 23%, mesmo com tendência de maior OPG, principalmente na fase inicial, indicando uma possível maior capacidade de adaptação à infecção por endoparasitas.

Assuntos

RESUMO

The aim of this study was to compare the following four genetic groups of hair sheep: Santa Inês (SI), Morada Nova (MN), Brazilian Somali (BS), and the F1 1/2Dorper x 1/2Morada Nova crossbreed on traits related to growth and parasitic infection. Thirty-three male lambs of the same age and of simple birth, under the same pre-weaning management conditions were used in the experiment. After weaning the animals were housed in a completely randomized design in paddocks made of Panicum maximum cv. Tanzania. Along the course of the research, the performance of the four groups of sheep was observed to be negatively affected by gastrointestinal parasites, but there was a genotype effect to the average daily weight gain (ADWG), where the SI and F1 genotypes presented higher values. The effects of genotype, time and genotype x time interaction were significant in weight and corporal score (CS) measurements. The BS lambs had the highest CS values throughout the experiment despite not presenting greater weight gain when compared to the SI and F1 breeds. There were also significant effects of time and genotype x time interaction for packed cell volume (PCV) and FAMACHA© score (FAM) and only the time effect was significant in the total number of eggs per gram (EPG) and total plasma protein (TPP). The MN lambs showed higher PCV values and unlike the other groups, presented a FAMACHA© score below 3 and PCV above 23% even having a higher EPG tendency, especially in the initial phase, indicating a possible higher resilience to infection caused by gastrointestinal parasites(AU)

O objetivo deste estudo foi comparar quatro grupos genéticos de ovinos: Santa Inês (SI), Somalis Brasileira (SB), Morada Nova (MN) e 1/2 Dorper - 1/2 Morada Nova (F1) quanto às características de crescimento e de infecção parasitária. Trinta e três cordeiros machos, de mesma idade, nascidos de parto simples e submetidos às mesmas condições de manejo pré-desmame foram utilizados no experimento. Após o desmame, os animais foram alojados em piquetes de capim Panicum maximum cv. Tanzânia, em um sistema rotativo de pastejo sob um delineamento inteiramente ao acaso. Os resultados mostraram que, ao longo do experimento, o desempenho ponderal dos quatro grupos genéticos foi negativamente afetado pela infecção por endoparasitas, mas o efeito de genótipo foi significativo para ganho de peso médio diário, e os grupos SI e F1 apresentaram melhores médias. O efeito do genótipo, tempo e interação genótipo x tempo foi significativo para o peso e o escore corporal. Os cordeiros da raça SB apresentaram maiores escores corporais ao longo do experimento, apesar do menor ganho de peso quando comparados aos dos grupos SI e F1. Houve efeito significativo do tempo e da interação genótipo x tempo para o hematócrito e para o grau FAMACHA©. Somente efeito do tempo foi verificado para as características OPG e proteína plasmática total. Os cordeiros da raça Morada Nova, ao contrário dos demais grupos, mantiveram o grau FAMACHA© inferior a 3 e hematócrito inferior a 23%, mesmo com tendência de maior OPG, principalmente na fase inicial, indicando uma possível maior capacidade de adaptação à infecção por endoparasitas(AU)

Assuntos

RESUMO

El siguiente artículo tuvo como objetivo presentar los significados psicológicos que se construyen en torno a la psicología jurídica, por psicólogos, abogados y estudiantes de psicología. Para la recolección de información se utilizó como técnica las Redes Semánticas Naturales. Se encontró que las palabras asociadas al estímulo Psicología Jurídica, son congruentes con las definiciones que tradicionalmente se brindan en torno a la misma, que no son muy distantes los definidores utilizados por cada grupo, que la organización jerárquica que cada grupo le asigna a los definidores es diferente, y que la predominancia es el de relacionar la psicología jurídica con el ejercicio de la psicología forense.

The following article aims to present the psychological meanings that are built around legal psychology, by psychologists, lawyers and students of psychology. Natural Semantic Networks were used to collect and process data. It was found that the words associated to the expression "Legal Psychology" are consistent with the traditional definitions; that the definers used by each group are close together, that the hierarchical organization each group assigns to the definer is different, and that the predominance is to relate legal psychology to the practice of forensic psychology.