Semi-Arid Environmental Conditions and Agronomic Traits Impact on the Grain Quality of Diverse Maize Genotypes.

We assessed the impact of environmental conditions and agronomic traits on maize grain quality parameters. The study was conducted using genotypes with distinct genetic constitutions developed specifically for late sowing in semi-arid environments. We evaluated the agronomic, physical, and chemical characteristics of eight maize open-pollinated varieties, six inbred lines, and three commercial hybrids. The yield of the open-pollinated varieties showed a positive correlation with protein content (r = 0.33), while it exhibited a negative correlation with the carbohydrate percentage (r = -0.36 and -0.42) in conjunction with the inbred lines. The flotation index of the hybrids was influenced primarily by the environmental effect (50.15%), whereas in the inbred lines it was nearly evenly divided between the genotype effect (45.51%) and the environmental effect (43.15%). In the open-pollinated varieties, the genotype effect accounted for 35.09% and the environmental effect for 42.35%. The characteristics of plant structure were associated with grain quality attributes relevant for milling, including hardness and test weight. Inbred lines exhibited significant genotype contributions to grain hardness, protein, and carbohydrate content, distinguishing them from the other two germplasm types. These associations are crucial for specific genotypes and for advancing research and development of cultivars for the food industry.

Modeling of fruit growth of tangor murcott and incidence of environmental factors on the estimated parameters / Modelación de crecimiento de frutos de tangor murcott e incidencia de factores medioambientales sobre los parámetros estimados

ABSTRACT Fruit production forecasts are a tool to plan the harvest and improve market strategies. To carry it out, it is essential to have information about the behavior of fruit development over time. The objective of this work was to find the mathematical-statistical model that best describes the growth pattern of tangor murcott fruit (Citrus reticulata x C. sinensis 'Murcott') and analyze how it is affected by environmental conditions. For this, in nine orchards, located in four locations in the province of Corrientes, Argentina, the equatorial diameter of 2,053 fruit from 82 days after full flowering to harvest were periodically registered during five seasons. The nonlinear models were compared: Logistic, Gompertz, Brody, Von Bertalanffy, Weibull, Morgan Mercer Flodin (MMF), Richards, and their respective re-parameterizations. The magnitudes of nonlinearity measures, coefficient of determination and estimates of residual deviation were considered as the main goodness-of-fit criteria. The selected model-parameterization combination was the fifth parameterization of the Logistic model with random effects on its three parameters. An Analysis of Variance model on the estimates of these parameters for each fruit showed that orchard and season factors were an important source of variability, mainly in those related to the initial size of the fruit and their growth rate. These results will allow the construction of growth tables, which in addition to making yield predictions, can be used to estimate fruit size distribution at harvest and improve the cultural practice of manual fruit thinning.

RESUMEN Los pronósticos de producción de fruta son una herramienta para planificar la cosecha y mejorar estrategias de mercado. Para su realización es imprescindible contar con información acerca del desarrollo de los frutos a lo largo del tiempo. El objetivo del presente trabajo fue encontrar el modelo matemático-estadístico que mejor describa el patrón de crecimiento de frutos tangor murcott (Citrus reticulata x C. sinensis 'Murcott') y analizar cómo es afectado por condiciones medioambientales. En nueve huertos, ubicados en cuatro localidades en la provincia de Corrientes, Argentina, se registró durante cinco temporadas el diámetro ecuatorial de 2053 frutos desde los 82 días después de plena floración hasta el momento de cosecha. Se compararon los modelos no lineales: Logístico, Gompertz, Brody, Von Bertalanffy, Weibull, Morgan Mercer Flodin (MMF), Richards, y sus respectivas re-parameterizaciones. Como principales criterios de bondad de ajuste se consideraron las magnitudes de medidas de no linealidad, coeficiente de determinación y estimaciones del desvío residual. La combinación modelo-parametrización seleccionada fue la quinta parametrización del modelo Logístico con efectos aleatorios en sus tres parámetros. Un modelo de análisis de la variancia sobre las estimaciones de estos parámetros para cada fruto mostró que los factores huerto y temporada eran una importante fuente de variabilidad, principalmente en los relacionados con el tamaño inicial de los frutos y su tasa de crecimiento. Estos resultados permitirán construir tablas de crecimiento, que además de realizar predicciones de rendimientos, podrán ser utilizadas para estimar distribución de tamaños de fruto a cosecha y mejorar la práctica cultural de raleo.

Phenotypic Analysis of Fourier-Transform Infrared Milk Spectra in Dairy Goats.

The infrared spectrum of bovine milk is used to predict many interesting traits, whereas there have been few studies on goat milk in this regard. The objective of this study was to characterize the major sources of variation in the absorbance of the infrared spectrum in caprine milk samples. A total of 657 goats belonging to 6 breeds and reared on 20 farms under traditional and modern dairy systems were milk-sampled once. Fourier-transform infrared (FTIR) spectra were taken (2 replicates per sample, 1314 spectra), and each spectrum contained absorbance values at 1060 different wavenumbers (5000 to 930 × cm-1), which were treated as a response variable and analyzed one at a time (i.e., 1060 runs). A mixed model, including the random effects of sample/goat, breed, flock, parity, stage of lactation, and the residual, was used. The pattern and variability of the FTIR spectrum of caprine milk was similar to those of bovine milk. The major sources of variation in the entire spectrum were as follows: sample/goat (33% of the total variance); flock (21%); breed (15%); lactation stage (11%); parity (9%); and the residual unexplained variation (10%). The entire spectrum was segmented into five relatively homogeneous regions. Two of them exhibited very large variations, especially the residual variation. These regions are known to be affected by the absorbance of water, although they also exhibited wide variations in the other sources of variation. The average repeatability of these two regions were 45% and 75%, whereas for the other three regions it was about 99%. The FTIR spectrum of caprine milk could probably be used to predict several traits and to authenticate the origin of goat milk.

Is single-step genomic REML with the algorithm for proven and young more computationally efficient when less generations of data are present?

Efficient computing techniques allow the estimation of variance components for virtually any traditional dataset. When genomic information is available, variance components can be estimated using genomic REML (GREML). If only a portion of the animals have genotypes, single-step GREML (ssGREML) is the method of choice. The genomic relationship matrix (G) used in both cases is dense, limiting computations depending on the number of genotyped animals. The algorithm for proven and young (APY) can be used to create a sparse inverse of G (GAPY~-1) with close to linear memory and computing requirements. In ssGREML, the inverse of the realized relationship matrix (H-1) also includes the inverse of the pedigree relationship matrix, which can be dense with a long pedigree, but sparser with short. The main purpose of this study was to investigate whether costs of ssGREML can be reduced using APY with truncated pedigree and phenotypes. We also investigated the impact of truncation on variance components estimation when different numbers of core animals are used in APY. Simulations included 150K animals from 10 generations, with selection. Phenotypes (h2 = 0.3) were available for all animals in generations 1-9. A total of 30K animals in generations 8 and 9, and 15K validation animals in generation 10 were genotyped for 52,890 SNP. Average information REML and ssGREML with G-1 and GAPY~-1 using 1K, 5K, 9K, and 14K core animals were compared. Variance components are impacted when the core group in APY represents the number of eigenvalues explaining a small fraction of the total variation in G. The most time-consuming operation was the inversion of G, with more than 50% of the total time. Next, numerical factorization consumed nearly 30% of the total computing time. On average, a 7% decrease in the computing time for ordering was observed by removing each generation of data. APY can be successfully applied to create the inverse of the genomic relationship matrix used in ssGREML for estimating variance components. To ensure reliable variance component estimation, it is important to use a core size that corresponds to the number of largest eigenvalues explaining around 98% of total variation in G. When APY is used, pedigrees can be truncated to increase the sparsity of H and slightly reduce computing time for ordering and symbolic factorization, with no impact on the estimates.

The estimation of variance components is computationally expensive under large-scale genetic evaluations due to several inversions of the coefficient matrix. Variance components are used as parameters for estimating breeding values in mixed model equations (MME). However, resulting breeding values are not Best Linear Unbiased Predictions (BLUP) unless the variance components approach the true parameters. The increasing availability of genomic data requires the development of new methods for improving the efficiency of variance component estimations. Therefore, this study aimed to reduce the costs of single-step genomic REML (ssGREML) with the Algorithm for Proven and Young (APY) for estimating variance components with truncated pedigree and phenotypes using simulated data. In addition, we investigated the influence of truncation on variance components and genetic parameter estimates. Under APY, the size of the core group influences the similarity of breeding values and their reliability compared to the full genomic matrix. In this study, we found that to ensure reliable variance component estimation, it is required to consider a core size that corresponds to the number of largest eigenvalues explaining around 98% of the total variation in G to avoid biased parameters. In terms of costs, the use of APY slightly decreased the time for ordering and symbolic factorization with no impact on estimations.

A new Bayesian approach for QTL mapping of family data.

In this paper, we propose a new Bayesian approach for QTL mapping of family data. The main purpose is to model a phenotype as a function of QTLs' effects. The model considers the detailed familiar dependence and it does not rely on random effects. It combines the probability for Mendelian inheritance of parents' genotype and the correlation between flanking markers and QTLs. This is an advance when compared with models which use only Mendelian segregation or only the correlation between markers and QTLs to estimate transmission probabilities. We use the Bayesian approach to estimate the number of QTLs, their location and the additive and dominance effects. We compare the performance of the proposed method with variance component and LASSO models using simulated and GAW17 data sets. Under tested conditions, the proposed method outperforms other methods in aspects such as estimating the number of QTLs, the accuracy of the QTLs' position and the estimate of their effects. The results of the application of the proposed method to data sets exceeded all of our expectations.

Mega-environment analysis of maize breeding data from Brazil

The development and recommendation of single cross maize hybrids (SH) to be used in extensive land areas (mega-environments), and in different crop seasons requires many experiments under numerous environmental conditions. The question we asked is if the data from these multi-environment experiments are sufficient to identify the best hybrid combinations. The aim of this study was to critically analyze the phenotype data of experiments of yield, established by a large seed producing company, under a high level of imbalance. Data from evaluation of 2770 SH were used from experiments conducted over four years, involving the first and second crop seasons, in 50 locations of different years and regions of Brazil. Different types of analysis were carried out and genetic and non-genetic components were estimated, with emphasis on the different interactions of the SH with the environments. Results showed that the coincidence of common hybrids in these experiments is normally small. The estimates of the correlations between of the hybrids coinciding in the environments two by two is of low magnitude. The hybrid × crop season interaction was always expressive; however, the interactions of hybrids and other environmental variables were also important. Under these conditions, alternatives were discussed for making with the information obtained from the experiments, can be more efficient on the process to obtain new hybrids by companies.

Mega-environment analysis of maize breeding data from Brazil

ABSTRACT: The development and recommendation of single cross maize hybrids (SH) to be used in extensive land areas (mega-environments), and in different crop seasons requires many experiments under numerous environmental conditions. The question we asked is if the data from these multi-environment experiments are sufficient to identify the best hybrid combinations. The aim of this study was to critically analyze the phenotype data of experiments of yield, established by a large seed producing company, under a high level of imbalance. Data from evaluation of 2770 SH were used from experiments conducted over four years, involving the first and second crop seasons, in 50 locations of different years and regions of Brazil. Different types of analysis were carried out and genetic and non-genetic components were estimated, with emphasis on the different interactions of the SH with the environments. Results showed that the coincidence of common hybrids in these experiments is normally small. The estimates of the correlations between of the hybrids coinciding in the environments two by two is of low magnitude. The hybrid × crop season interaction was always expressive; however, the interactions of hybrids and other environmental variables were also important. Under these conditions, alternatives were discussed for making with the information obtained from the experiments, can be more efficient on the process to obtain new hybrids by companies.

Mega-environment analysis of maize breeding data from Brazil

The development and recommendation of single cross maize hybrids (SH) to be used in extensive land areas (mega-environments), and in different crop seasons requires many experiments under numerous environmental conditions. The question we asked is if the data from these multi-environment experiments are sufficient to identify the best hybrid combinations. The aim of this study was to critically analyze the phenotype data of experiments of yield, established by a large seed producing company, under a high level of imbalance. Data from evaluation of 2770 SH were used from experiments conducted over four years, involving the first and second crop seasons, in 50 locations of different years and regions of Brazil. Different types of analysis were carried out and genetic and non-genetic components were estimated, with emphasis on the different interactions of the SH with the environments. Results showed that the coincidence of common hybrids in these experiments is normally small. The estimates of the correlations between of the hybrids coinciding in the environments two by two is of low magnitude. The hybrid × crop season interaction was always expressive; however, the interactions of hybrids and other environmental variables were also important. Under these conditions, alternatives were discussed for making with the information obtained from the experiments, can be more efficient on the process to obtain new hybrids by companies.

Genetic selection indices for growth traits in Blanco-Orejinegro cattle.

Selection indices are used in genetic improvement programs, with the purpose of selectins simultaneous for several economically important traits. The objective of this study was to construct equations for selection indices in the Blanco-Orejinegro (BON) breed and to determine the index that would generate the greatest genetic progress. The information used included birth weight (BW), body weights adjusted to 120, 240, 480, and 720 days old (W120, W240, W240, 480 and W720, respectively), age at first calving (AFC) and interval between first and second calving (IBC) estimated breeding values. Two Smith and Hazel indices were calculated using variances (I1) and literature (I2), with a part two indices designed using information from experts and breeders (I3 and I4). All the indices favored the reduction of weight at birth. The I1 focused mainly on W120 and I2, I3 and I4 focused on 720. In general, the estimated indices obtained similar reliability and expected genetic differences I1 generated a decrease in direct BW. I2 generated the largest increases in BW and AFC. I3 and I4 generated positive changes in growth and reproductive traits, with I3 generating the greatest genetic gains in the population, especially for W240.

Genetic evaluation for reproductive and productive traits in Brahman cattle.

Our objectives were to estimate genetic parameters for male and female reproductive traits and their genetic correlations with body weight and carcass traits, evaluate the genetic trends over the years, and verify the effect of inbreeding on the phenotypes of Brahman cattle. The traits evaluated were body weights at 120, 210, 365, and 450 days of age (W120, W210, W365, and W450); scrotal circumference at 365 and 450 days of age (SC365 and SC450), age at first calving (AFC), gestation length (GL), stayability (STAY), ribeye area (REA), backfat thickness (BFT), and rump fat thickness (RFT). Direct heritability estimates ranged from 0.10 ± 0.03 (AFC) to 0.43 ± 0.06 (GL). Maternal heritability estimates for body weights, scrotal circumferences, and GL ranged from 0.07 ± 0.02 to 0.15 ± 0.03. The proportion of the maternal permanent environment for W120 and W210 was equal to 0.11 ± 0.02. Genetic correlations varied between -0.60 ± 0.25 (STAY and BFT) to 0.97 ± 0.01 (W365 and W450). Except for AFC, all genetic trends were significant (p < 0.05) and presented favorable annual genetic gains. Unfavorable effects due to the increase of inbreeding coefficients were observed for body weights and AFC, suggesting greater attention be paid to the applied mating systems to control inbreeding. Reproductive traits, such as AFC and STAY, could be assisted indirectly by scrotal circumference selection. The emphasis applied to body weight selection, especially at W210, may assist REA. The BFT and RFT traits presented genetic variability and have responded to selection, although not included in the Brahman selection index.

Genetic principal components for reproductive and productive traits in Holstein cows reared under tropical conditions.

The objective of this study was to compare the standard multi-trait model and five reduced-rank models fitted to the first principal components and genetic parameter estimates in order to determine the most appropriate method to model the covariance structure of reproductive and productive traits in Brazilian Holstein cows. Individual records of the following traits from 5217 cows were analyzed: 305-day milk yield (MY305), peak yield, milk yield per day of calving interval, days from calving to first estrus, days from calving to last service (CLS), calving interval (CI), and gestation length. Schwarz's Bayesian information criterion was used to compare the different models. The results indicated that four principal components were necessary to model the genetic (co)variance structure, reducing the number of parameters to be estimated. Analysis of genetic and phenotypic correlations showed that milk production-related traits were strongly correlated with each other (ranging from 0.74 to 0.99), while the correlation of these traits with the reproductive traits was weak (ranging from - 0.14 to 0.27). Heritability estimates for the traits ranged from 0.03 to 0.18. The reproductive traits CLS and CI and the production trait MY305 should be included as selection criteria in dairy cattle breeding programs because they are correlated with the first two principal components, retaining 91% of the genetic variability of the data.

Genetic parameters of girolando crossbred cows in dairy herds in the State of Acre, Brazil / Parâmetros genéticos de vacas mestiças girolando em rebanhos leiteiros no Estado do Acre, Brasil / Parámetros genéticos de vacas cruzadas girolando en ganados lecheros en el Estado de Acre, Brasil

This study aimed at estimating genetic parameters for milk production and conformation characteristics in Girolando crossbred dairy cows reared in the High and Low Acre region using the restricted maximum likelihood methodology, under an animal model. We estimated the variance components and genetic parameters using the REML/BLUP procedure (Restricted Maximum Likelihood Methodology/Best Linear Unbiased Prediction). The estimated average for milk production for 305 days of lactation (P305) was of 1523.25 ± 481.11 kg, with a heritability of 0.38 for this characteristic. The conformation characteristics showed no significant correlation with milk production. The phenotypical correlations between the linear characteristics of type were, in general, positive and moderate. The P305 obtained in this study can be considered low and indicates that there is a possibility of increasing milk production through selection in herds along with the use of tested and proven bulls. The heritability estimate found (0.38) indicates that there is genetic variability for milk production, demonstrating that selection for this characteristic would result in genetic progress.(AU)

Este estudo teve como objetivo estimar parâmetros genéticos para produção de leite e características de conformação em vacas leiteiras mestiças Girolando criadas na região do Alto e Baixo Acre, utilizando a metodologia da máxima verossimilhança restrita, sob modelo animal. As estimativas dos componentes de variância e dos parâmetros genéticos foram realizadas pelo procedimento REML/BLUP (Máxima verossimilhança restrita/Melhor predição linear não viesada). A média estimada para produção de leite aos 305 dias de lactação (P305) foi de 1.523,25 ± 481 kg e a herdabilidade para esta característica foi de 0,38. As características de conformação não apresentaram correlação significativa com a produção de leite. As correlações fenotípicas entre as características lineares de tipo foram em geral positivas e de magnitude moderada. A P305 obtida neste estudo pode ser considerada baixa e indica que existe a possibilidade de aumento da produção de leite através de seleção nos rebanhos, juntamente com a utilização de touros testados e provados. A estimativa de herdabilidade encontrada (0,38) indica que há variabilidade genética para produção de leite, demonstrando que a seleção para esta característica resultaria em progresso genético.(AU)

El objetivo del estudio fue estimar los parámetros genéticos para la producción de leche y las características de conformación en vacas lecheras cruzadas Girolando criadas en la región de Alto y Bajo Acre utilizando el método de máxima verosimilitud restringida, con un modelo animal. Estimamos los componentes de la varianza y los parámetros genéticos mediante el procedimiento REML / BLUP (metodología de máxima verosimilitud restringida / mejor predicción lineal insesgada). El promedio estimado para la producción de leche para los 305 días de lactancia (P305) fue de 1523.25 ± 481.11 kg, con una heredabilidad de 0.38 para esta característica. Las características de conformación no mostraron correlación significativa con la producción de leche. Las correlaciones fenotípicas entre las características lineales de tipo fueron, en general, positivas y moderadas. El P305 obtenido en este estudio puede considerarse bajo y muestra que existe la posibilidad de incrementar la producción de leche a través de la selección en rebaños, junto con el uso de toros probados y comprobados. La estimación de heredabilidad encontrada (0,38) indica que existe variabilidad genética para la producción de leche, lo que demuestra que la selección de esta característica daría lugar a un progreso genético.(AU)

Genetic parameters of girolando crossbred cows in dairy herds in the State of Acre, Brazil / Parâmetros genéticos de vacas mestiças girolando em rebanhos leiteiros no Estado do Acre, Brasil / Parámetros genéticos de vacas cruzadas girolando en ganados lecheros en el Estado de Acre, Brasil

This study aimed at estimating genetic parameters for milk production and conformation characteristics in Girolando crossbred dairy cows reared in the High and Low Acre region using the restricted maximum likelihood methodology, under an animal model. We estimated the variance components and genetic parameters using the REML/BLUP procedure (Restricted Maximum Likelihood Methodology/Best Linear Unbiased Prediction). The estimated average for milk production for 305 days of lactation (P305) was of 1523.25 ± 481.11 kg, with a heritability of 0.38 for this characteristic. The conformation characteristics showed no significant correlation with milk production. The phenotypical correlations between the linear characteristics of type were, in general, positive and moderate. The P305 obtained in this study can be considered low and indicates that there is a possibility of increasing milk production through selection in herds along with the use of tested and proven bulls. The heritability estimate found (0.38) indicates that there is genetic variability for milk production, demonstrating that selection for this characteristic would result in genetic progress.(AU)

Este estudo teve como objetivo estimar parâmetros genéticos para produção de leite e características de conformação em vacas leiteiras mestiças Girolando criadas na região do Alto e Baixo Acre, utilizando a metodologia da máxima verossimilhança restrita, sob modelo animal. As estimativas dos componentes de variância e dos parâmetros genéticos foram realizadas pelo procedimento REML/BLUP (Máxima verossimilhança restrita/Melhor predição linear não viesada). A média estimada para produção de leite aos 305 dias de lactação (P305) foi de 1.523,25 ± 481 kg e a herdabilidade para esta característica foi de 0,38. As características de conformação não apresentaram correlação significativa com a produção de leite. As correlações fenotípicas entre as características lineares de tipo foram em geral positivas e de magnitude moderada. A P305 obtida neste estudo pode ser considerada baixa e indica que existe a possibilidade de aumento da produção de leite através de seleção nos rebanhos, juntamente com a utilização de touros testados e provados. A estimativa de herdabilidade encontrada (0,38) indica que há variabilidade genética para produção de leite, demonstrando que a seleção para esta característica resultaria em progresso genético.(AU)

El objetivo del estudio fue estimar los parámetros genéticos para la producción de leche y las características de conformación en vacas lecheras cruzadas Girolando criadas en la región de Alto y Bajo Acre utilizando el método de máxima verosimilitud restringida, con un modelo animal. Estimamos los componentes de la varianza y los parámetros genéticos mediante el procedimiento REML / BLUP (metodología de máxima verosimilitud restringida / mejor predicción lineal insesgada). El promedio estimado para la producción de leche para los 305 días de lactancia (P305) fue de 1523.25 ± 481.11 kg, con una heredabilidad de 0.38 para esta característica. Las características de conformación no mostraron correlación significativa con la producción de leche. Las correlaciones fenotípicas entre las características lineales de tipo fueron, en general, positivas y moderadas. El P305 obtenido en este estudio puede considerarse bajo y muestra que existe la posibilidad de incrementar la producción de leche a través de la selección en rebaños, junto con el uso de toros probados y comprobados. La estimación de heredabilidad encontrada (0,38) indica que existe variabilidad genética para la producción de leche, lo que demuestra que la selección de esta característica daría lugar a un progreso genético.(AU)

Parámetros genéticos para crecimiento y reproducción en ganado Simmental mediante parentesco por pedigrí y genómico / Genetic parameters for growth and reproduction in Simmental cattle from pedigree and genomic relationship

RESUMEN Objetivo. Estimar parámetros genéticos para peso a los ocho meses de edad (W8M), edad al primer parto (AFC) y primer intervalo entre partos (FCI) usando parentesco genómico y por pedigrí. Materiales y métodos. Se utilizaron 481, 3063 y 1098 registros fenotípicos para W8M, AFC y FCI, respectivamente. La información genómica estuvo compuesta por una población de 718 animales genotipados con un chip que incluyó 30106 marcadores genéticos tipo polimorfismo de nucleótido simple (SNP). Modelos univariado y bivariado fueron construidos bajo la metodología del mejor predictor lineal insesgado convencional (BLUP) y genómico en una etapa (ssGBLUP). Resultados. Las heredabilidades para W8M, AFC y FCI variaron desde 0.25 a 0.26, 0.20 a 0.22 y 0.04 a 0.08, respectivamente. Los modelos de AFC y FCI con la metodología ssGBLUP disminuyeron ligeramente el error y aumentaron la varianza genética aditiva, respectivamente. Conclusiones. La inclusión de información genómica mejora levemente la precisión de las estimaciones genéticas en esta población. Sin embargo, una población de animales genotipados más grande y con mayor conectividad genética por parentesco permitiría aumentar para los criadores el potencial de la metodología ssGBLUP en ganado Simmental de Colombia.

ABSTRACT Objective. To estimate genetic parameters for weight at eight months of age (W8M), age at first calving (AFC) and first calving interval (FCI) using pedigree and genomic relationship. Materials and methods. Phenotypic data on 481, 3063 and 1098 animals for W8M, AFC and FCI were used, respectively. The genomic information came from a population of 718 genotyped animals with a density chip of 30,106 single nucleotide polymorphism markers (SNP). Univariate and bivariate models were used under the conventional (BLUP) and single step genomic best linear unbiased predictor (ssGBLUP) methodologies. Results. The heritabilities for W8M, AFC and FCI ranged from 0.25 to 0.26, from 0.20 to 0.22 and from 0.04 to 0.08, respectively. The AFC and FCI models under ssGBLUP slightly decreased the error and increased the additive genetic variance, respectively. Conclusions. The inclusion of genomic information slightly increases the accuracy of the genetic estimates in this population. However, a larger amount of genotyped animals and with a higher genetic relationship connectivity would allow breeders to increase the potential of the ssGBLUP methodology in Colombian Simmental cattle.

Genetic parameters between somatic cell score and production traits for Holstein cattle in Southern Brazil / Parámetros genéticos entre el conteo de células somáticas y las características productivas de bovinos Holstein del Sur de Brasil / Parâmetros genéticos entre escore de células somáticas e características produtivas em bovinos da raça Holandesa do Sul do Brasil

Abstract Background: Somatic cell score is an important parameter to predict milk quality and health of cows. However, in countries like Brazil, this trait is still not selected on a large scale, and no genetic parameters are reported in the literature. Objective: To estimate the variance components and genetic parameters for somatic cell score, milk yield, fat yield, protein yield, fat percentage, and protein percentage in Holstein cows. Methods: Records from 56,718 animals were used to estimate variance components, heritability, and genetic correlations using a multi-trait animal model by the REML method. Results: The heritability estimates were 0.19 for somatic cell score, 0.22 for milk yield, 0.26 for fat yield, 0.18 for protein yield, 0.61 for fat percentage, and 0.65 for protein percentage. The estimates of genetic correlations among analyzed traits ranged from -0.50 to 0.82. Conclusion: The low heritability observed for somatic cell score indicates that selection for this trait should result in benefits related to animal health and milk quality, but only in the long term. The low correlation between productive traits and somatic cell score indicates that inclusion of somatic cell score in animal breeding programs does not interfere negatively with the genetic selection for milk yield or solids.

Resumen Antecedentes: El conteo de células somáticas es un parámetro importante para predecir la calidad de la leche y la salud de las vacas. Sin embargo, en países como Brasil, esta característica aún no se selecciona a gran escala y no se reportan parámetros genéticos en la literatura. Objetivo: Estimar los componentes de varianza y parámetros genéticos para el conteo de células somáticas, producción de leche, producción de grasa, producción de proteína, porcentaje de grasa y porcentaje de proteína en vacas de la raza Holstein. Métodos: Se usaron registros de 56.718 animales para estimar los componentes de la varianza, heredabilidad y correlaciones genéticas usando un modelo animal multicaracterístico por medio del método REML. Resultados: Las estimaciones de heredabilidad fueron 0,19 para el conteo de células somáticas, 0,22 para la producción de leche, 0,26 para la producción de grasa, 0,18 para producción de proteína, 0,61 para el porcentaje de grasa y 0,65 para el porcentaje de proteína. Las estimaciones de correlación genética entre las características analizadas variaron entre -0,50 a 0,82. Conclusión: La baja heredabilidad encontrada para conteo de células somáticas demostró que la selección para esta característica podría resultar en beneficios para la salud animal y calidad de la leche, pero sólo a largo plazo. La baja correlación genética existente entre las características productivas y el conteo de células somáticas indica que la inclusión del conteo de células somáticas en programas de selección no interfiere negativamente en la selección genética para la producción de leche o sólidos.

Resumo Antecedentes: O escore de células somáticas é um parâmetro importante para a predição da qualidade do leite, bem como para a saúde das vacas. No entanto, em alguns países como o Brasil, essa característica não é selecionada em larga escala e não há parâmetros genéticos disponíveis na literatura. Objetivo: Estimar os componentes de variância e parâmetros genéticos para o escore de células somáticas, produção de leite, produção de gordura, produção de proteína, porcentagem de gordura e porcentagem de proteína em vacas da raça Holandesa. Métodos: Foi utilizado um total de 56.718 animais para estimar os componentes de variância, herdabilidade e correlações genéticas, considerando-se o modelo animal multicaracterística por meio do método REML. Resultados: As estimativas de herdabilidade foram de 0,19 para o escore de células somáticas, 0,22 para a produção de leite, 0,26 para a produção de gordura, 0,18 para produção de proteína, 0,61 para a porcentagem de gordura e 0,65 para a porcentagem de proteína. As estimativas de correlação genética entre as características analisadas variaram entre -0,50 a 0,82. Conclusão: A baixa herdabilidade encontrada para o escore de células somáticas demonstrou que a seleção para esta característica poderá resultar em benefícios para a saúde animal e qualidade do leite, porém, somente a longo prazo. A baixa correlação genética existente entre as características produtivas e o escore de células somáticas demonstrou que a inclusão do escore de células somáticas em programas de seleção não causa interferência negativa na seleção genética para a produção de leite ou sólidos.

Parámetros genéticos para producción de leche en ganado Simmental (Bos taurus) mediante modelos genómicos y poligénicos / Genetic parameters for milk production in Simmental cattle (Bos taurus) using genomic and polygenic models

RESUMEN El objetivo de este estudio fue estimar parámetros genéticos con y sin la inclusión de parentesco genómico para la producción de leche acumulada a 60 (PL60), 150 (PL150), 210 (PL210) y 305 días (PL305) en ganado Simmental en Colombia. Un total de 2883 controles lecheros en 620 vacas de primer parto fueron utilizados. La información genómica se obtuvo a partir de 718 animales genotipados con un chip de una densidad de 30106 marcadores genéticos tipo polimorfismo de nucleótido simple (SNP). Se construyeron modelos de tipo univariado y bivariado bajo la metodología del mejor predictor lineal insesgado (BLUP) y genómico en una etapa (ssGBLUP). Los valores de heredabilidades para PL60, PL150, PL210 y PL305 variaron entre 0,20 a 0,27; 0,25 a 052; 0,30 a 0,35 y 0,20 a 0,23; respectivamente. La inclusión de parentesco genómico no aumentó las heredabilidades y tampoco la precisión de las estimaciones para las características asociadas a producción de leche. La escasez de información fenotípica y la baja conectividad genética entre la población genotipada y no genotipada podrían limitar procesos de selección genética para producción de leche a través del ssGBLUP en la población de ganado Simmental de Colombia.

ABSTRACT The aim of this study was to estimate genetic parameters with and without the inclusion of genomic relationship in cumulative milk production of Simmental cattle in Colombia for 60 (MP60), 150 (MP150), 210 (MP210) and 305 (MP305) days. A total of 2883 test records from 620 cows in first lactation were used. The genomic information was obtained from 718 animals genotyped with a commercial chip with a density of 30,106 single nucleotide polymorphism (SNP) genetic markers. Univariate and bivariate models were used under the conventional best linear unbiased predictor (BLUP) and the single step genomic BLUP (ssGBLUP) methodologies. The heritability estimate values for MP60, MP150, MP210 and MP305 ranged from 0.20 to 0.27, 0.25 to 0.52, 0.30 to 0.35 and 0.20 to 0.23, respectively. The use of the genomic relationship did not increase heritabilities nor the accuracy of estimates for milk traits. The lack of phenotypic records and the low genetic connectivity between genotyped and non-genotyped populations could limit the genetic selection procedures for milk production via the ssGBLUP in Colombian Simmental cattle.

Seed local adaptation and seedling plasticity account for Gleditsia triacanthos tree invasion across biomes.

BACKGROUND AND AIMS: Phenotypic plasticity and local adaption can contribute to the success of invasive species. While the former is an environmentally induced trait, the latter involves a selection process to filter the best genotype for a location. We examined the evidence for phenotypic plasticity and local adaptation for seed and seedling traits of the invasive tree Gleditsia triacanthos, with three origins distributed along an approx. 10° latitude gradient across three biomes. METHODS: In sub-tropical forests, dry woodlands and secondary temperate grasslands in Argentina, we harvested seeds from clusters of neighbouring trees (i.e. families) distributed within 15-20 km in each origin (biome). We manipulated the environmental conditions relevant to each biome, assuming that propagule availability did not represent an ecological barrier. In growth chambers, we evaluated seed imbibition and seed germination under different light, temperature and water potential. In a 2 year common garden, we evaluated the impact of resident vegetation removal on seedling survival and growth. KEY RESULTS: Mean time to complete seed imbibition differed among origins; seeds from temperate grasslands reached full imbibition before seeds from dry woodlands and sub-tropical forests. Germination was always >70 %, but was differentially affected by water potential, and light quantity (dark-light) and quality (red-far red) among origins, suggesting local adaptation. In the common garden, vegetation removal rather than origin negatively affected seedling survival and enhanced seedling growth. Vegetation removal increased basal diameter, leaves per plant and spine number, and reduced the height:basal diameter ratio. CONCLUSIONS: We conclude that local adaptation in seed germination traits and plastic changes in seedling allometry (e.g. height:diameter) may allow this tree to respond over the short and long term to changes in environmental conditions, and to contribute to shape G. triacanthos as a successful woody invader. Overall, our study revealed how local adaptation and plasticity can explain different aspects of tree invasion capacity across biomes.

Does trait variation within broadly distributed species mirror patterns across species? A case study in Puerto Rico.

Although populations are phenotypically diverse, the majority of trait-based studies have focused on examining differences among species. The justification for this broadly applied approach is based on the assumption that differences among species are always greater than within species. This is likely true for local communities, but species are often broadly distributed across a wide range of environments and patterns of intraspecific variation might surpass differences among species. Therefore, an appropriate interpretation of the functional diversity requires an assessment of patterns of trait variation across different ecological scales. In this study, we examine and characterize patterns of leaf trait variation for species that are broadly distributed along an elevational gradient. We focus on seven leaf traits that represent a main axis of functional differentiation in plants reflecting the balance between photosynthetic efficiency, display, and stomatal conductance. We evaluated patterns of trait variance across ecological scales (elevation, species, populations, and individuals) and examined trait covariance at both within species and across species levels, along the elevation gradient. Our results show three key patterns: (1) intraspecific leaf trait variation for broadly distributed species is comparable to the interspecific trait variation, (2) the trait variance structure is highly variable across species, and (3) trait coordination between pairs of leaf traits is evident across species along the gradient, but not always within species. Combined, our results show that trait coordination and covariance are highly idiosyncratic across broadly distributed and co-occurring species, indicating that species may achieve similar functional roles even when exhibiting different phenotypes. This result challenges the traditional paradigm of functional ecology that assumes single trait values as optimal solutions for environments. In conclusion, patterns of trait variation both across and within species should be considered in future studies that assess trade-offs among traits over environmental gradients.

Estimação de parâmetros genéticos para características de pesos e pesos metabólicos na desmama e pós-desmama em bovinos Brahman / Estimation of genetic parameters for weaning weights and metabolic weights characteristics and post weaning in Brahman cattle

Objetivou-se estimar herdabilidades e correlações de características ponderais com 36.505 animais, da Associação Brasileira de Criadores Zebu. O modelo incluiu efeito genético direto, materno, ambiente permanente, residual - aleatórios e efeitos de grupos contemporâneos - fixos. Os parâmetros foram estimados pelo método de máxima verossimilhança restrita (REML), utilizando-se software Wombat. Os resultados das herdabilidades variaram de 0,20 a 0,25 peso à desmama e ao sobreano; 0,16 a 0,20 peso metabólico não ajustado e ajustado à desmama, 0,21 a 0,25 peso metabólico ajustado à desmama e metabólico ajustado ao sobreano. As correlações genéticas entre peso à desmama e peso metabólico não ajustado à desmama, peso à desmama e peso metabólico ajustado à desmama são, respectivamente 0,76 e 1,00. A correlação genética entre peso ao sobreano e metabólico ao sobreano não ajustado, peso ao sobreano com metabólico sobreano ajustado foram 0,97 e 1,00. Correlação genética entre peso à desmama e ao sobreano foi 0,72, peso metabólico não ajustado à desmama e metabólico não ajustado ao sobreano 0,54, peso metabólico ajustado à desmama e metabólico ajustado ao sobreano foi 0,71. Correlações genéticas entre peso à desmama e metabólico ajustado à desmama e peso ano com metabólico ano ajustado foram 1,00 e 1,00. Portanto, utilização de peso metabólico sem ajuste de idade pode viesar estimativas de parâmetros genéticos.(AU)

The objective of this study was to estimate heritability and correlations of 36,505 animals, belonging to the Brazilian Association of Zebu Breeders. They were estimated by Restricted Maximum Likelihood method (REML) using Wombat software. The model included the direct additive genetic effect, maternal, permanent maternal environment and residual as random and fixed effects of contemporary group. The results of heritability ranged from 0,20 to 0,25 for weaning weight and yearling; 0,16 to 0,20 for real metabolic weaning, 0,21 to 0,25 for metabolic adjusted weight at weaning and yearling metabolic adjusted. The genetic correlations between weaning weight with metabolic real, weaning weight adjusted with metabolic are respectively 0,76 and 1,00. The genetic correlation between yearling weight and metabolic real, yearling weight adjusted metabolic were 0,97 and 1,00. Genetic correlations between weaning weight and yearling was 0,72, real metabolic weight at weaning and yearling real metabolic was 0,54, adjusted metabolic weight at weaning and yearling metabolic adjusted was 0,71. Genetic correlations between weight at weaning and adjusted metabolic and weight-adjusted metabolic year were 1,00 and 1,00. Therefore, the use of metabolic weight without age adjustment can warn the estimates.(AU)

Estimação de parâmetros genéticos para características de pesos e pesos metabólicos na desmama e pós-desmama em bovinos Brahman / Estimation of genetic parameters for weaning weights and metabolic weights characteristics and post weaning in Brahman cattle

Objetivou-se estimar herdabilidades e correlações de características ponderais com 36.505 animais, da Associação Brasileira de Criadores Zebu. O modelo incluiu efeito genético direto, materno, ambiente permanente, residual - aleatórios e efeitos de grupos contemporâneos - fixos. Os parâmetros foram estimados pelo método de máxima verossimilhança restrita (REML), utilizando-se software Wombat. Os resultados das herdabilidades variaram de 0,20 a 0,25 peso à desmama e ao sobreano; 0,16 a 0,20 peso metabólico não ajustado e ajustado à desmama, 0,21 a 0,25 peso metabólico ajustado à desmama e metabólico ajustado ao sobreano. As correlações genéticas entre peso à desmama e peso metabólico não ajustado à desmama, peso à desmama e peso metabólico ajustado à desmama são, respectivamente 0,76 e 1,00. A correlação genética entre peso ao sobreano e metabólico ao sobreano não ajustado, peso ao sobreano com metabólico sobreano ajustado foram 0,97 e 1,00. Correlação genética entre peso à desmama e ao sobreano foi 0,72, peso metabólico não ajustado à desmama e metabólico não ajustado ao sobreano 0,54, peso metabólico ajustado à desmama e metabólico ajustado ao sobreano foi 0,71. Correlações genéticas entre peso à desmama e metabólico ajustado à desmama e peso ano com metabólico ano ajustado foram 1,00 e 1,00. Portanto, utilização de peso metabólico sem ajuste de idade pode viesar estimativas de parâmetros genéticos.(AU)

The objective of this study was to estimate heritability and correlations of 36,505 animals, belonging to the Brazilian Association of Zebu Breeders. They were estimated by Restricted Maximum Likelihood method (REML) using Wombat software. The model included the direct additive genetic effect, maternal, permanent maternal environment and residual as random and fixed effects of contemporary group. The results of heritability ranged from 0,20 to 0,25 for weaning weight and yearling; 0,16 to 0,20 for real metabolic weaning, 0,21 to 0,25 for metabolic adjusted weight at weaning and yearling metabolic adjusted. The genetic correlations between weaning weight with metabolic real, weaning weight adjusted with metabolic are respectively 0,76 and 1,00. The genetic correlation between yearling weight and metabolic real, yearling weight adjusted metabolic were 0,97 and 1,00. Genetic correlations between weaning weight and yearling was 0,72, real metabolic weight at weaning and yearling real metabolic was 0,54, adjusted metabolic weight at weaning and yearling metabolic adjusted was 0,71. Genetic correlations between weight at weaning and adjusted metabolic and weight-adjusted metabolic year were 1,00 and 1,00. Therefore, the use of metabolic weight without age adjustment can warn the estimates.(AU)