RESUMO

Gastrointestinal nematode infections have caused expressive losses in sheep production worldwide. The improvement of host genetic resistance to worms has been used as a strategy to mitigate this problem. In this sense, the inclusion of genomic information has shown potential to increase the accuracy of prediction of breeding values and speed up selection. In this study, we aimed to compare estimates of genetic parameters and breeding values for traits that indicate the resistance to gastrointestinal nematode infection in Santa Inês sheep using the pedigree-based BLUP or including genomic information. There were 1478 animals in the pedigree, of which 271 were genotyped using the OvineSNP50 BeadChip (Illumina, Inc.). The host resistance was assessed using the following traits: fecal nematode egg counts (FEC); FAMACHA score (FAMACHA); and resistance to gastrointestinal nematode infection (RGNI) as a combination of FEC, FAMACHA, body condition score, and hematocrit. The genetic parameters and breeding values were estimated using single- and multi-trait analyses. For RGNI, the heritability estimates ranged from 0.25 using the single-trait genomic model (S-H) to 0.54 using the traditional multi-trait model (M-A). The heritability estimates for FEC ranged from 0.06 to 0.36, using the single-trait pedigree-based model (S-A) and the multi-trait genomic model (M-H), respectively. For FAMACHA, the heritability estimates ranged from 0.46 (M-H) to 0.54 (M-A). Estimates of genetic correlation ranged from 0.22 to 0.69. The inclusion of genomic information provided gain in accuracy for all traits. All estimates of predictive ability obtained using genomic data in a multi-trait setting were higher than those obtained using single-trait models. The estimates of predictive ability ranged from 0.03 (S-A) to 0.46 (M-H). The heritability estimates obtained using genomic information showed that all traits evaluated are suitable for genomic selection. Despite the low accuracies obtained, the use of the genomic model provided more accurate estimates of breeding values in comparison to the pedigree-based model.

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RESUMO

OBJECTIVE: The genetic evaluation of Santa Inês sheep was performed for resistance to gastrointestinal nematode infection (RGNI) and body size using different relationship matrices to assess the efficiency of including genomic information in the analyses. METHODS: There were 1,637 animals in the pedigree and 500, 980, and 980 records of RGNI, thoracic depth (TD), and rump height (RH), respectively. The genomic data consisted of 42,748 SNPs and 388 samples genotyped with the OvineSNP50 BeadChip. The (co)variance components were estimated in single- and multi-trait analyses using the numerator relationship matrix (A) and the hybrid matrix H, which blends A with the genomic relationship matrix (G). The BLUP and single-step genomic BLUP methods were used. The accuracies of estimated breeding values and Spearman rank correlation were also used to assess the feasibility of incorporating genomic information in the analyses. RESULTS: The heritability estimates ranged from 0.11±0.07, for TD (in single-trait analysis using the A matrix), to 0.38±0.08, for RH (using the H matrix in multi-trait analysis). The estimates of genetic correlation ranged from -0.65±0.31 to 0.59±0.19, using A, and from -0.42±0.30 to 0.57±0.16 using H. The gains in accuracy of estimated breeding values ranged from 2.22% to 75.00% with the inclusion of genomic information in the analyses. CONCLUSION: The inclusion of genomic information will benefit the direct selection for the traits in this study, especially RGNI and TD. More information is necessary to improve the understanding on the genetic relationship between resistance to nematode infection and body size in Santa Inês sheep. The genetic evaluation for the evaluated traits was more efficient when genomic information was included in the analyses.

RESUMO

OBJECTIVE: The objective of this study was to estimate the genetic parameters for worm resistance (WR) and associated characteristics, using the linear-threshold animal model via Bayesian inference in single- and multiple-trait analyses. METHODS: Data were collected from a herd of Santa Inês breed sheep. All information was collected with animals submitted to natural contamination conditions. All data (number of eggs per gram of feces [FEC], Famacha score [FS], body condition score [BCS], and hematocrit [HCT]) were collected on the same day. The animals were weighed individually on the day after collection (after 12-h fasting). The WR trait was defined by the multivariate cluster analysis, using the FEC, HCT, BCS, and FS of material collected from naturally infected sheep of the Santa Inês breed. The variance components and genetic parameters for the WR, FEC, HCT, BCS, and FS traits were estimated using the Bayesian inference under the linear and threshold animal model. RESULTS: A low magnitude was obtained for repeatability of worm-related traits. The mean values estimated for heritability were of low-to-high (0.05 to 0.88) magnitude. The FEC, HCT, BCS, FS, and body weight traits showed higher heritability (although low magnitude) in the multiple-trait model due to increased information about traits. All WR characters showed a significant genetic correlation, and heritability estimates ranged from low (0.44; single-trait model) to high (0.88; multiple-trait model). CONCLUSION: Therefore, we suggest that FS be included as a criterion of ovine genetic selection for endoparasite resistance using the trait defined by multivariate cluster analysis, as it will provide greater genetic gains when compared to any single trait. In addition, its measurement is easy and inexpensive, exhibiting greater heritability and repeatability and a high genetic correlation with the trait of resistance to worms.

RESUMO

Objetivou-se verificar as condições higienicossanitárias dos boxes de comercialização de pescado no Mercado Público José Emídio, localizado no município de Timon, Maranhão. Foram aplicados checklists considerando os aspectos higiênicos e sanitários dos proprietários dos boxes e realizou-se a coleta de amostras dos alimentos comercializados nesses estabelecimentos para avaliação microbiológica, bem como amostras, por meio de swab, das mãos, realizando a determinação do número mais provável de coliformes a 35° e a 45° C. Tais procedimentos foram posteriores a apresentação, leitura e assinatura do Termo de Consentimento Livre e Esclarecido. Por meio da porcentagem de "SIM" às respostas dos itens do checklist, os boxes foram diagnosticados com 24,14; 31,03 e 48,00% para A, B e C, respectivamente, sendo os três estabelecimentos classificados como irregulares. Nas análises microbiológicas verificou-se que há presença de coliformes totais na maioria das amostras de pescado, indicando condições higienicossanitárias insatisfatórias dos alimentos comercializados nos boxes pesquisados. Todavia, nas análises referentes aos manipuladores, verificou-se que somente um apresentou resultado de contaminação microbiológica. Tais resultados evidenciam a necessidade de análise microbiológica dos alimentos, auxiliando a identificação de qual momento está ocorrendo o processo de contaminação do pescado. A aplicação somente do checklist é ineficiente para avaliação das condições higienicossanitárias de estabelecimento comercializadores de pescado.(AU)

It was aimed to verify the hygienic- sanitary conditions of fish comercilizers boxes in the José Emídio Public Market, located in the Timon city, Maranhão. They were applied "checklist" considering the hygienic-sanitary aspects of the Manipulators of the boxes and the samples of the foods commercialized collected in out for microbiological evaluation, as well as samples by hand swab, making the determination of the most probable number of coliforms at 35° and 45º C. Such procedures were subsequent to the presentation, reading and signing of the Termod and Free and Scantily Consented. Through the "YES" percentage of responses to Checklist items, the boxes were diagnosed with 24,14, 31,03 and 48,00% for A, B and C, respectively, and the three establishments were classified as irregular. In the microbiological analyzes it was verified that there is presence of total coliforms in the majority of fish samples, indicating unsatisfactory hygienic-sanitary conditions of the foods commercialized in the researched boxes. However, in the analyzes referring to the manipulators, it was verified that only one presented a result of microbiological contamination. These results evidenced the need for microbiological analysis of the food, helping to identify which moment the process of fish contamination is occurring. The only application of the "checklist" is inefficient to evaluate the hygienicsanitary conditions of fish traders.(AU)

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RESUMO

Objetivou-se verificar as condições higienicossanitárias dos boxes de comercialização de pescado no Mercado Público José Emídio, localizado no município de Timon, Maranhão. Foram aplicados checklists considerando os aspectos higiênicos e sanitários dos proprietários dos boxes e realizou-se a coleta de amostras dos alimentos comercializados nesses estabelecimentos para avaliação microbiológica, bem como amostras, por meio de swab, das mãos, realizando a determinação do número mais provável de coliformes a 35º e a 45º C. Tais procedimentos foram posteriores a apresentação, leitura e assinatura do Termo de Consentimento Livre e Esclarecido. Por meio da porcentagem de "SIM" às respostas dos itens do checklist, os boxes foram diagnosticados com 24,14; 31,03 e 48,00% para A, B e C, respectivamente, sendo os três estabelecimentos classificados como irregulares. Nas análises microbiológicas verificou-se que há presença de coliformes totais na maioria das amostras de pescado, indicando condições higienicossanitárias insatisfatórias dos alimentos comercializados nos boxes pesquisados. Todavia, nas análises referentes aos manipuladores, verificou-se que somente um apresentou resultado de contaminação microbiológica. Tais resultados evidenciam a necessidade de análise microbiológica dos alimentos, auxiliando a identificação de qual momento está ocorrendo o processo de contaminação do pescado. A aplicação somente do checklist é ineficiente para avaliação das condições higienicossanitárias de estabelecimento comercializadores de pescado.(AU)

It was aimed to verify the hygienic-sanitary conditions of fish comercilizers boxes in the José Emídio Public Market, located in the Timon city, Maranhão. They were applied "checklist" considering the hygienic-sanitary aspects of the Manipulators of the boxes and the samples of the foods commercialized collected in out for microbiological evaluation, as well as samples by hand swab, making the determination of the most probable number of coliforms at 35º and 45º C. Such procedures were subsequent to the presentation, reading and signing of the Termod and Free and Scantily Consented. Through the "YES" percentage of responses to Checklist items, the boxes were diagnosed with 24,14, 31,03 and 48,00% for A, B and C, respectively, and the three establishments were classified as irregular. In the microbiological analyzes it was verified that there is presence of total coliforms in the majority of fish samples, indicating unsatisfactory hygienic-sanitary conditions of the foods commercialized in the researched boxes. However, in the analyzes referring to the manipulators, it was verified that only one presented a result of microbiological contamination. These results evidenced the need for microbiological analysis of the food, helping to identify which moment the process of fish contamination is occurring. The only application of the "checklist" is inefficient to evaluate the hygienicsanitary conditions of fish traders.

Assuntos

RESUMO

OBJECTIVE: The aim of this study was to estimate (co) variance components and genetic parameters for categorical carcass traits using Bayesian inference via mixed linear and threshold animal models in Anglonubian goats. METHODS: Data were obtained from Anglonubian goats reared in the Brazilian Mid-North region. The traits in study were body condition score, marbling in the rib eye, ribeye area, fat thickness of the sternum, hip height, leg perimeter, and body weight. The numerator relationship matrix contained information from 793 animals. The single- and two-trait analyses were performed to estimate (co) variance components and genetic parameters via linear and threshold animal models. For estimation of genetic parameters, chains with 2 and 4 million cycles were tested. An 1,000,000-cycle initial burn-in was considered with values taken every 250 cycles, in a total of 4,000 samples. Convergence was monitored by Geweke criteria and Monte Carlo error chain. RESULTS: Threshold model best fits categorical data since it is more efficient to detect genetic variability. In two-trait analysis the contribution of the increase in information and the correlations between traits contributed to increase the estimated values for (co) variance components and heritability, in comparison to single-trait analysis. Heritability estimates for the study traits were from low to moderate magnitude. CONCLUSION: Direct selection of the continuous distribution of traits such as thickness sternal fat and hip height allows obtaining the indirect selection for marbling of ribeye.

RESUMO

The aim of this study was to estimate the variance components and genetic parameters for marbling in the ribeye area (MRA) and body condition score (BCS) using Bayesian inference via mixed linear and threshold animal models. Data were obtained from Santa Ines breed sheep reared in the Brazilian Mid-North region. Analyses considering the Monte Carlo methods were performed with Markov chains from 500000 cycles onward. A 200000-cycle initial burn-in was considered with values taken at every 250 cycles, in a total of 1200 samples. The Monte Carlo Error deviations were low for the means heritability in all chains by both linear and threshold models. Additive variances estimated by threshold model were higher than those estimated by the linear model. Marble meat from the ribeye area and body condition score can be used as selection criteria to obtain genetic progress in Santa Inês sheep. (AU)

O objetivo deste estudo foi estimar componentes de variância e parâmetros genéticos para marmoreio na área de olho de lombo (MOL) e escore de condição corporal (ECC) usando Inferência Bayesiana por meio dos modelos animais linear misto e de limiar. Os dados foram obtidos em rebanhos de ovinos da raça Santa Inês criados no Meio-Norte do Brasil. As análises, considerando os métodos de Monte Carlo, foram realizadas com cadeias de Markov a partir de 500000 ciclos. Considerou-se burn-in inicial de 200000 ciclos com valores tomados a cada 250 ciclos, obtendo-se 1200 amostras. Os desvios do erro de Monte Carlo foram baixos para as herdabilidades médias em todas as cadeias, tanto pelo modelo linear quanto de limiar. As variâncias aditivas, estimadas pelo modelo de limiar, foram maiores que aquelas obtidas pelo modelo linear. O marmoreio na área de olho de lombo e o escore da condição corporal podem ser usados como critérios de seleção para obter progresso genético em ovinos da raça Santa Inês. (AU)

Assuntos

RESUMO

The aim of this study was to estimate the variance components and genetic parameters for marbling in the ribeye area (MRA) and body condition score (BCS) using Bayesian inference via mixed linear and threshold animal models. Data were obtained from Santa Ines breed sheep reared in the Brazilian Mid-North region. Analyses considering the Monte Carlo methods were performed with Markov chains from 500000 cycles onward. A 200000-cycle initial burn-in was considered with values taken at every 250 cycles, in a total of 1200 samples. The Monte Carlo Error deviations were low for the means heritability in all chains by both linear and threshold models. Additive variances estimated by threshold model were higher than those estimated by the linear model. Marble meat from the ribeye area and body condition score can be used as selection criteria to obtain genetic progress in Santa Inês sheep.

O objetivo deste estudo foi estimar componentes de variância e parâmetros genéticos para marmoreio na área de olho de lombo (MOL) e escore de condição corporal (ECC) usando Inferência Bayesiana por meio dos modelos animais linear misto e de limiar. Os dados foram obtidos em rebanhos de ovinos da raça Santa Inês criados no Meio-Norte do Brasil. As análises, considerando os métodos de Monte Carlo, foram realizadas com cadeias de Markov a partir de 500000 ciclos. Considerou-se burn-in inicial de 200000 ciclos com valores tomados a cada 250 ciclos, obtendo-se 1200 amostras. Os desvios do erro de Monte Carlo foram baixos para as herdabilidades médias em todas as cadeias, tanto pelo modelo linear quanto de limiar. As variâncias aditivas, estimadas pelo modelo de limiar, foram maiores que aquelas obtidas pelo modelo linear. O marmoreio na área de olho de lombo e o escore da condição corporal podem ser usados como critérios de seleção para obter progresso genético em ovinos da raça Santa Inês.

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RESUMO

This study was carried out to evaluate the effects of heterogeneity of residual variance on genetic evaluation of cattle raised on pasture from Amazônia Bioma, Brazil. Adjusted weights at weaning weight (205 days of age) were sorted in three phenotypic classes: low (less than average weight), medium (between the average and the average plus one standard deviation) and high (greater than average plus one standard deviation). There was increased of genetic additive direct and residual variances to the extent that increased phenotypic classes. The heritabilities for low, medium and high phenotypic classes were 0.27, 0.33 and 0.26, respectively. These estimates suggest that mass selection could result in genetic gain on breeding program that use weaning weight as a selection criteria. Genetic correlations between the low and medium, low and high, and medium and high phenotypic classes were 0.82, 0.35 and 0.72, respectively. The estimate of correlation of the breeding values of sire shown effect of the heterogeneity of phenotypic variance on the prediction of animals breeding values. There was a major variability for the breeding values of sires at high phenotype class. Thus, we suggested the identification and selection of sires with the highest breeding values for weaning weight, according with environment in which these animals are being raised.

Objetivou-se descrever o quantitativo, distribuição e estrutura do rebanho de ovino da raça Santa Inês no estado do Piauí. Foram analisados dados de registros genealógicos da raça Santa Inês, mantidos pela Associação Brasileira de Criadores de Ovinos (ARCO), referentes ao período de 1992 a 2012. Foram realizadas análises estatísticas descritivas de modo a conhecer como o rebanho Santa Inês está estruturado. Foi realizada a classificação do rebanho quanto a sua estrutura organizacional, determinada com base na origem e uso dos reprodutores, utilizando-se o programa ENDOG. v.4.8. O registro dos animais da raça Santa Inês, no Piauí, teve inicio em 1990, e a maior representatividade foi verificada no período de 1993 a 2001. Quanto à estrutura dos rebanhos, 56,8% foram classificados como rebanhos multiplicadores (estrato intermediário da pirâmide) e 43,2% como rebanhos comerciais (base da pirâmide), sendo que não se observou nenhum rebanho núcleo e nem isolado. A falta de rebanhos núcleo da raça no Estado pode ser uma das causas da redução do número de animais registrados nos últimos anos no Piauí.

Assuntos

RESUMO

This study was carried out to evaluate the effects of heterogeneity of residual variance on genetic evaluation of cattle raised on pasture from Amazônia Bioma, Brazil. Adjusted weights at weaning weight (205 days of age) were sorted in three phenotypic classes: low (less than average weight), medium (between the average and the average plus one standard deviation) and high (greater than average plus one standard deviation). There was increased of genetic additive direct and residual variances to the extent that increased phenotypic classes. The heritabilities for low, medium and high phenotypic classes were 0.27, 0.33 and 0.26, respectively. These estimates suggest that mass selection could result in genetic gain on breeding program that use weaning weight as a selection criteria. Genetic correlations between the low and medium, low and high, and medium and high phenotypic classes were 0.82, 0.35 and 0.72, respectively. The estimate of correlation of the breeding values of sire shown effect of the heterogeneity of phenotypic variance on the prediction of animals breeding values. There was a major variability for the breeding values of sires at high phenotype class. Thus, we suggested the identification and selection of sires with the highest breeding values for weaning weight, according with environment in which these animals are being raised.(AU)

Objetivou-se descrever o quantitativo, distribuição e estrutura do rebanho de ovino da raça Santa Inês no estado do Piauí. Foram analisados dados de registros genealógicos da raça Santa Inês, mantidos pela Associação Brasileira de Criadores de Ovinos (ARCO), referentes ao período de 1992 a 2012. Foram realizadas análises estatísticas descritivas de modo a conhecer como o rebanho Santa Inês está estruturado. Foi realizada a classificação do rebanho quanto a sua estrutura organizacional, determinada com base na origem e uso dos reprodutores, utilizando-se o programa ENDOG. v.4.8. O registro dos animais da raça Santa Inês, no Piauí, teve inicio em 1990, e a maior representatividade foi verificada no período de 1993 a 2001. Quanto à estrutura dos rebanhos, 56,8% foram classificados como rebanhos multiplicadores (estrato intermediário da pirâmide) e 43,2% como rebanhos comerciais (base da pirâmide), sendo que não se observou nenhum rebanho núcleo e nem isolado. A falta de rebanhos núcleo da raça no Estado pode ser uma das causas da redução do número de animais registrados nos últimos anos no Piauí.(AU)

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RESUMO

Objetivou-se avaliar a influência de alguns efeitos não genéticos sobre características da carcaça de caprinos, medidas por ultrassom. Além disso, estimar correlações simples entre características de carcaça mapeadas com uso de ultrassonografia, com escore da condição corporal e com os parâmetros da curva de crescimento ajustados a pesos de caprinos criados na microrregião de Teresina, PI. Os modelos Gompertz, Logístico, Von Bertalanffy, Brody e Richards foram ajustados para descrição da curva. No processo de pesquisa, foram atribuídas notas subjetivas de escore da condição corporal de 1 a 5 pontos, e mensuradas área de olho de lombo, profundidade de olho de lombo e espessura da gordura esternal, por meio de imagem ultrassonográficas. No modelo sistematizado, foram considerados os efeitos ambientais de mês da mensuração, tipo de nascimento, sexo, rebanho e raça, sem relegar as diferentes matrizes de covariância utilizadas. Estimou-se correlações de Pearson entre as medidas de características da carcaça mensuradas com ultrassom, o escore da condição corporal e os parâmetros da curva de crescimento ajustada. Constatou-se, por fim, que o modelo de Gompertz foi o de melhor ajuste na descrição da curva de crescimento. Os efeitos fixos de raça, rebanho, sexo, tipo de nascimento e mês de mensuração, nessa ordem de influência, se apresentaram como responsáveis por grande variação nas medidas das características de carcaça. Os parâmetros da curva ajustada de Gompertz e as características de carcaça apresentaram baixa correlação. O Escore da condição corporal não se mostrou como um bom indicador para as medidas das características de carcaça.

This work aimed to evaluate the influence of some non-genetic effects on goat's carcass traits measured by ultrasound, as well as estimate simple correlations between carcass traits obtained with the use of ultrasound, with body condition score and growth curve parameters fitted to the weight of goats in the micro-region of Teresina-PI. Gompertz, Logistic, Von Bertalanffy, Brody and Richards models were fitted for curve description. Were assigned grades subjective 1 to 5 points of body condition score and eye muscle area, eye muscle depth, and breast bone fat thickness were measured by ultrasound images. Environmental effects of month of measurement, type of birth, sex, herd and breed were considered, as well as different used matrices of (co) variance. Pearson's correlations among measures of carcass traits measured by ultrasound, body condition score, and the fitted growth curve parameters were estimated. The Gompertz model was the best fit in growth curve description. The fixed effects of breed, herd, sex, type of birth, and month measurement, in this order of influence, presented themselves as responsible for a large variation in measures carcass traits. The Gompertz fitted curve parameters and carcass traits present low correlation. The body condition score did not prove to be a good a good indicator for measures carcass traits.

Assuntos

RESUMO

Objetivou-se avaliar a influência de alguns efeitos não genéticos sobre características da carcaça de caprinos, medidas por ultrassom. Além disso, estimar correlações simples entre características de carcaça mapeadas com uso de ultrassonografia, com escore da condição corporal e com os parâmetros da curva de crescimento ajustados a pesos de caprinos criados na microrregião de Teresina, PI. Os modelos Gompertz, Logístico, Von Bertalanffy, Brody e Richards foram ajustados para descrição da curva. No processo de pesquisa, foram atribuídas notas subjetivas de escore da condição corporal de 1 a 5 pontos, e mensuradas área de olho de lombo, profundidade de olho de lombo e espessura da gordura esternal, por meio de imagem ultrassonográficas. No modelo sistematizado, foram considerados os efeitos ambientais de mês da mensuração, tipo de nascimento, sexo, rebanho e raça, sem relegar as diferentes matrizes de covariância utilizadas. Estimou-se correlações de Pearson entre as medidas de características da carcaça mensuradas com ultrassom, o escore da condição corporal e os parâmetros da curva de crescimento ajustada. Constatou-se, por fim, que o modelo de Gompertz foi o de melhor ajuste na descrição da curva de crescimento. Os efeitos fixos de raça, rebanho, sexo, tipo de nascimento e mês de mensuração, nessa ordem de influência, se apresentaram como responsáveis por grande variação nas medidas das características de carcaça. Os parâmetros da curva ajustada de Gompertz e as características de carcaça apresentaram baixa correlação. O Escore da condição corporal não se mostrou como um bom indicador para as medidas das características de carcaça.(AU)

This work aimed to evaluate the influence of some non-genetic effects on goat's carcass traits measured by ultrasound, as well as estimate simple correlations between carcass traits obtained with the use of ultrasound, with body condition score and growth curve parameters fitted to the weight of goats in the micro-region of Teresina-PI. Gompertz, Logistic, Von Bertalanffy, Brody and Richards models were fitted for curve description. Were assigned grades subjective 1 to 5 points of body condition score and eye muscle area, eye muscle depth, and breast bone fat thickness were measured by ultrasound images. Environmental effects of month of measurement, type of birth, sex, herd and breed were considered, as well as different used matrices of (co) variance. Pearson's correlations among measures of carcass traits measured by ultrasound, body condition score, and the fitted growth curve parameters were estimated. The Gompertz model was the best fit in growth curve description. The fixed effects of breed, herd, sex, type of birth, and month measurement, in this order of influence, presented themselves as responsible for a large variation in measures carcass traits. The Gompertz fitted curve parameters and carcass traits present low correlation. The body condition score did not prove to be a good a good indicator for measures carcass traits.(AU)

Assuntos