Genetic control of quality melon traits / Controle genético de caracteres de qualidade do melão

ABSTRACT: This research studied the genetic control of the traits related to melon fruit quality. The F1, F2, BC1, BC2 generations from the OL x A-16 and OL x PV crossings were evaluated in two separate trials conducted in randomized blocks with three replications. The evaluated traits were: average fruit weight, shape index, pulp thickness, pulp firmness, soluble solids content and cracking rate. The analyses were accomplished through a classic study of generations involving mixed models. The parameters on heritability and number of loci controlling the traits were evaluated in a broad and narrow sense. The inheritance of the evaluated traits is complex, presenting one gene of greater effect and polygenes with additive and dominant effects.

RESUMO: Objetivou-se com este trabalho estudar o controle genético de caracteres relacionados à qualidade do fruto do melão. Foram avaliadas as gerações F1, F2, RC1, RC2 dos cruzamentos OL x A-16 e OL x PV em dois ensaios separados conduzidos em blocos casualizados com três repetições. Os caracteres avaliados foram: peso médio do fruto, índice de formato, espessura da polpa, firmeza da polpa, sólidos solúveis e porcentagem de rachadura. As análises foram feitas por meio de estudo clássico de gerações envolvendo modelos mistos. Foram estimados os parâmetros de herdabilidades nos sentidos amplo e restrito e número de loci que controlam o caráter. A herança dos caracteres estudados é complexa com a presença de gene de efeito maior e poligenes com efeitos aditivos e de dominância.

Morpho-agronomic and leaf anatomical traits in Coffeacanephora genotypes / Caracteres morfoagronômicos e anatômicos foliares em genótipos de Coffea canephora

ABSTRACT: Genetic variability is the basis for coffee genetic breeding. This study evaluated the potential of leaf anatomy and morpho-agronomic traits in studies of genetic variability in C. canephoracultivars. Ten genotypes were distributed in randomized block designs with three replicates. Significant differences among genotypes were detected by F-test (P < 0.05) for 13 of 15 evaluated traits. These results evidenced the heterogeneity of the studied cultivars, which is essential in composition of genetic basis in breeding programs. The Scott-Knott test detected variability among genotypes, grouped into up to four mean groups. Leaf anatomy traits presented the largest variations. Five out of seven leaf anatomy traits presented heritability higher than 80%, with emphasis on stomatal density (95.69%) and stomatal pore length (92.72%). Positive correlations were observed among morpho-agronomic and anatomic traits. Cluster analysis used the Mahalanobis general distance (D2) as a measure of genetic dissimilarity and divided the genotypes into two distinct groups. The inclusion of leaf anatomic traits to characterize C. canephoragenotypes may assist plant breeders with better genetic discrimination and with greater security in plant selection when composing cultivars.

RESUMO: A variabilidade genética é a base para o progresso genético em café. Este estudo teve como objetivo, avaliar o potencial de caracteres morfoagronômicos e anatômicos foliares em estudos de variabilidade genética entre cultivares de Coffea canephora. Dez genótipos foram distribuídos em um experimento seguindo delineamento em blocos ao acaso com três repetições. Foram detectadas diferenças significativas entre os genótipos pelo teste F (P < 0,05) para 13 dos 15 caracteres avaliados. Esses resultados evidenciaram a heterogeneidade entre as cultivares estudadas, o que é essencial para a composição da base genética e avanço dos programas de melhoramento. O teste de Scott e Knott detectou as diferenças entre os genótipos, separando-os em quatro grupos. Os caracteres anatômicos foliares apresentaram as maiores variações. Cinco, dentre os sete caracteres anatômicos foliares, apresentaram estimativas de herdabilidade superiores a 80% com destaque para a densidade estomática (95,69%) e comprimento do poro estomático (92,72%). Correlações positivas foram observadas entre caracteres morfoagronômicos e anatômicos foliares. A análise de agrupamento, considerando a distância de Mahalanobis como medida de dissimilaridade (D²), apontou a distinção de dois grupos de genótipos. A inclusão de caracteres anatômicos foliares na caracterização de genótipos de C. canephora pode auxiliar os melhoristas de plantas na melhor discriminação entre genótipos e maior segurança na seleção de clones para geração de novas cultivares.

Environmental variability in indirect selection for grain yield in common bean lines

An approach to the number of experiments that should be used in correlation analyses aimed at increasing efficiency in indirect selection for grain yield is unprecedented for common bean (Phaseolus vulgaris L.). We hypothesize that trait correlation estimates vary in response to the growing environment. This study was undertaken to investigate the correlations between plant architecture and yield traits in common bean lines and to determine the minimum number of experiments required by Pearson's linear correlation analysis to increase efficiency in indirect selection for grain yield. Seventeen common bean genotypes were evaluated for 17 agronomic traits in four experiments. Pearson's linear correlation analyses were carried out using data from individual experiments and different combinations of growing seasons and years. Ten out of the 17 agronomic traits showed a significant genotype × environment interaction effect, meaning that common bean genotypes exhibited variation for most of the traits evaluated in different growing seasons and years, which resulted in changes in the correlation estimates between these traits. Pearson's linear correlation estimates obtained between plant architecture and yield traits varied in significance, magnitude, and sign when data from individual experiments and combinations of growing seasons and years were considered. The number of grains per pod is the most promising agronomic trait used in indirect selection for grain yield in common bean lines. Data from at least three experiments should be used in Pearson's linear correlation analysis to achieve greater efficiency in indirect selection for grain yield in common bean lines.

Sampling sufficiency, correlation and path analysis in showy rattlebox / Suficiência amostral, correlação e análise de trilha em crotalária spectabilis

It is important to adequately size the number of plants that should be evaluated to allow precise inferences about the traits under evaluation. The study of the linear relations among traits provides important information, especially in the identification of traits for indirect selection. So, the objectives of this work were to determine the sample size (number of plants) to estimate the mean of Crotalaria spectabilis traits and investigate the relations among traits. Were randomly selected 200 and 110 plants of C. spectabilis in the experiments conducted, respectively, in 2019/2020 and 2020/2021. In these 310 plants, the following traits were evaluated: plant height, stem diameter, number of nodes, number of leaves, leaf fresh matter, stem fresh matter, shoot fresh matter, leaf dry matter, stem dry matter and shoot dry matter. The sample size was calculated to estimate the mean of these traits, based on Student's t-distribution, and the relations among traits were investigated through correlation and path analysis. To estimate the mean of these ten traits of C. spectabilis, with a maximum error of 10% of the mean and 95% confidence level, 64 plants are needed. In an experiment, to estimate the mean of each treatment with 10% precision, 64 plants per treatment must be evaluated. The number of leaves has a positive linear relation with the amount leaf, stem and shoot fresh and dry matter.

É importante dimensionar adequadamente o número de plantas que devem ser avaliadas para possibilitar inferências precisas sobre os caracteres em avaliação. O estudo das relações lineares entre caracteres fornece informações importantes, especialmente, na identificação de caracteres para seleção indireta. Assim, os objetivos deste trabalho foram determinar o tamanho de amostra (número de plantas) necessário para a estimação da média de caracteres de Crotalaria spectabilis e investigar as relações entre os caracteres. Foram selecionadas, aleatoriamente, 200 e 110 plantas de C. spectabilis, nos experimentos conduzidos, respectivamente, em 2019/2020 e 2020/2021. Nessas 310 plantas avaliaram-se os caracteres altura de planta, diâmetro de caule, número de nós, número de folhas, matéria fresca de folhas, matéria fresca de caule, matéria fresca de parte aérea, matéria seca de folhas, matéria seca de caule e matéria seca de parte aérea. Foi calculado o tamanho de amostra para a estimação da média desses caracteres, com base na distribuição t de Student e investigada a relação entre os caracteres por meio de análises de correlação e de trilha. Para a estimação da média, desses dez caracteres de C. spectabilis, com erro máximo de 10% da média e grau de confiança de 95%, são necessárias 64 plantas. Em um experimento, para a estimação da média de cada tratamento com 10% de precisão, devem ser avaliadas 64 plantas por tratamento. O número de folhas tem relação linear positiva com a quantidade de matérias fresca e seca de folhas, do caule e de parte aérea.

Effects of amylin on egg quality traits of hens during the early laying period

This study was conducted to investigate the effects of amylin, a pancreatic hormone polypeptide, on egg quality traits in laying hens. A total of 40 birds (14 wk of age) were randomly divided into two treatments with two replicates, 10 birds in each replicate. Twenty birds were subcutaneously injected with amylin at 75 µg/kg every other day (treatment 1), and the remaining animals (20 hens) were given only water as the control group (treatment 2). Eggs collected from the two groups (140 eggs per group) were examined for several quality performance traits such as egg weight, specific gravity, shape index, eggshell strength, eggshell thickness, eggshell ash, eggshell weight, Haugh unit (HU), albumen index, yolk index, yolk color, and albumen height. The results indicated that amylin had a positive effect on some egg quality traits in laying hens. Specific gravity, eggshell thickness, eggshell weight, HU, albumen index, yolk index, and albumen height, which are all considered as important quality parameters from the consumer point of view, especially HU, were relatively improved in the amylin treatment group. These results showed that the injection of 75 µg/kg amylin has a significant effect on some egg quality traits. Considering that egg quality characteristics are crucial for the egg industry, this study can be a reference for the detailed investigation of the use of amylin in the different stages of egg production.

Canonical correlations between high and low heritability wheat traits via mixed models / Correlações canônicas entre caracteres de trigo de alta e baixa herdabilidade via modelos mistos

ABSTRACT: Canonical correlation analysis based on genotypic correlations allows determining the associations between groups of traits and carrying out the direct or indirect selection of superior genotypes. This study investigated the existence of linear and multivariate relationships between high and low heritability traits via canonical correlation analysis based on genotypic correlations. The experiment was conducted at the Professor Diogo Alves de Melo Experimental Field at the Universidade Federal de Viçosa, in Viçosa, MG. 90 wheat cultivars were evaluated under a 9 × 10 alpha-lattice design, with three replications and plots consisting of four rows of three meters spaced at 0.20 meters. Canonical groups were established between spike height and plant height, days for heading, number of spikelets per spike, and number of grains per spike (Group I) and, spike weight, spike grain mass, 100-grain mass, hectoliter weight, and grain yield (Group II). There was dependence between the established groups, which allowed the investigation of the relationships between traits based on their genotypic values. The traits cycle and plant height can be used for indirect selection of genotypes superior in hectoliter weight and grain yield, which are important factors for industries and farmers.

RESUMO: As análises de correlações canônicas baseadas nas correlações genotípicas, permitem determinar associações entre grupos de caracteres e realizar a seleção direta ou indireta de genótipos superiores. Objetivou-se com este trabalho investigar a existência de relações lineares e multivariadas entre caracteres de alta e baixa herdabilidade via análise de correlações canônicas com base nas correlações genotípicas. O experimento foi conduzido no Campo Experimental Professor Diogo Alves de Melo da Universidade Federal de Viçosa, em Viçosa, Minas Gerais. 90 cultivares de trigo foram avaliadas sob o delineamento alpha-lattice 9 × 10, com três repetições e parcelas constituídas por quatro linhas de três metros espaçadas a 0.20 metros. Os grupos canônicos foram estabelecidos entre altura de espiga e planta, dias para o espigamento, número de espiguetas por espiga e número de grãos por espiga (Grupo I) e, peso de espiga, massa de grãos da espiga, massa de 100 grãos, peso hectolitro e produtividade de grãos (Grupo II). Houve dependência entre os grupos estabelecidos, o que permitiu a investigação das relações entre os caracteres com base em seus valores genotípicos. Os caracteres ciclo e altura de plantas podem ser utilizados para a seleção indireta de genótipos superiores em peso hectolitro e produtividade, fatores estes importantes para indústrias e produtores.

Genome-enabled prediction through quantile random forest for complex traits / Predição genômica por meio do random forest quantílitico para características complexas

ABSTRACT: Quantile Random Forest (QRF) is a non-parametric methodology that combines the advantages of Random Forest (RF) and Quantile Regression (QR). Specifically, this approach can explore non-linear functions, determining the probability distribution of a response variable and extracting information from different quantiles instead of just predicting the mean. This evaluated the performance of the QRF in the genomic prediction for complex traits (epistasis and dominance). In addition, compare the accuracies obtained with those derived from the G-BLUP. The simulation created an F2 population with 1,000 individuals and genotyped for 4,010 SNP markers. Besides, twelve traits were simulated from a model considering additive and non-additive effects, QTL (Quantitative trait loci) numbers ranging from eight to 120, and heritability of 0.3, 0.5, or 0.8. For training and validation, the 5-fold cross-validation approach was used. For each fold, the accuracies of all the proposed models were calculated: QRF in five different quantiles and three G-BLUP models (additive effect, additive and epistatic effects, additive and dominant effects). Finally, the predictive performance of these methodologies was compared. In all scenarios, the QRF accuracies were equal to or greater than the methodologies evaluated and proved to be an alternative tool to predict genetic values in complex traits.

RESUMO: Quantile Random Forest (QRF) é uma metodologia não paramétrica, que combina as vantagens do Random Forest (RF) e da Regressão Quantílica (QR). Especificamente, essa abordagem pode explorar funções não lineares, determinando a distribuição de probabilidade de uma variável resposta e extraindo informações de diferentes quantis em vez de apenas prever a média. O objetivo deste trabalho foi avaliar o desempenho do QRF em predizer o valor genético genômico para características com arquitetura genética não aditiva (epistasia e dominância). Adicionalmente, as acurácias obtidas foram comparadas com aquelas advindas do G-BLUP. A simulação criou uma população F2 com 1.000 indivíduos genotipados para 4.010 marcadores SNP. Além disso, doze características foram simuladas a partir de um modelo considerando efeitos aditivos e não aditivos, com número de QTL (Quantitative trait loci) variando de oito a 120 e herdabilidade de 0,3, 0,5 ou 0,8. Para treinamento e validação foi usada a abordagem da validação cruzada 5-fold. Para cada um dos folds foram calculadas as acurácias de todos os modelos propostos: QRF em cinco quantis diferentes e três modelos do G-BLUP (com efeito aditivo, aditivo e epistático, aditivo e dominante). Por fim, o desempenho preditivo dessas metodologias foi comparado. Em todos os cenários, as acurácias do QRF foram iguais ou superiores às metodologias avaliadas e mostrou ser uma ferramenta alternativa para predizer valores genéticos em características complexas.

Canonical correlations between high and low heritability wheat traits via mixed models / Correlações canônicas entre caracteres de trigo de alta e baixa herdabilidade via modelos mistos

Canonical correlation analysis based on genotypic correlations allows determining the associations between groups of traits and carrying out the direct or indirect selection of superior genotypes. This study investigated the existence of linear and multivariate relationships between high and low heritability traits via canonical correlation analysis based on genotypic correlations. The experiment was conducted at the Professor Diogo Alves de Melo Experimental Field at the Universidade Federal de Viçosa, in Viçosa, MG. 90 wheat cultivars were evaluated under a 9 × 10 alpha-lattice design, with three replications and plots consisting of four rows of three meters spaced at 0.20 meters. Canonical groups were established between spike height and plant height, days for heading, number of spikelets per spike, and number of grains per spike (Group I) and, spike weight, spike grain mass, 100-grain mass, hectoliter weight, and grain yield (Group II). There was dependence between the established groups, which allowed the investigation of the relationships between traits based on their genotypic values. The traits cycle and plant height can be used for indirect selection of genotypes superior in hectoliter weight and grain yield, which are important factors for industries and farmers.

As análises de correlações canônicas baseadas nas correlações genotípicas, permitem determinar associações entre grupos de caracteres e realizar a seleção direta ou indireta de genótipos superiores. Objetivou-se com este trabalho investigar a existência de relações lineares e multivariadas entre caracteres de alta e baixa herdabilidade via análise de correlações canônicas com base nas correlações genotípicas. O experimento foi conduzido no Campo Experimental Professor Diogo Alves de Melo da Universidade Federal de Viçosa, em Viçosa, Minas Gerais. 90 cultivares de trigo foram avaliadas sob o delineamento alpha-lattice 9 × 10, com três repetições e parcelas constituídas por quatro linhas de três metros espaçadas a 0.20 metros. Os grupos canônicos foram estabelecidos entre altura de espiga e planta, dias para o espigamento, número de espiguetas por espiga e número de grãos por espiga (Grupo I) e, peso de espiga, massa de grãos da espiga, massa de 100 grãos, peso hectolitro e produtividade de grãos (Grupo II). Houve dependência entre os grupos estabelecidos, o que permitiu a investigação das relações entre os caracteres com base em seus valores genotípicos. Os caracteres ciclo e altura de plantas podem ser utilizados para a seleção indireta de genótipos superiores em peso hectolitro e produtividade, fatores estes importantes para indústrias e produtores.

Woody species distribution across a savanna-dry forest soil gradient in the Brazilian Cerrado

Abstract Although richness and distribution of woody species in the Cerrado physiognomies have been extensively studied, the shifts of woody species from savanna physiognomies to dry forests have not yet been addressed. Here, we investigate the effect of soil physical-chemical traits on the woody species turnover between adjacent cerrado stricto sensu and dry forest physiognomies. Woody species were surveyed, and soil and topographic variables measured, in 30 10×40 m plots systematically distributed, with 15 plots in each physiognomy. We found a spatially structured distribution of woody species, and differences of soil traits between cerrado stricto sensu and dry forest areas, mainly related to the aluminum saturation, base saturation, and available phosphorus. Aluminum saturation increased toward the savanna area, while base saturation increased toward the dry forest. Most woody species predominated in one physiognomy, such as Callisthene major in the cerrado stricto sensu and Anadenanthera colubrina in the dry forest. Only 20% of the species were widely distributed across both physiognomies or, not often, restricted to the intermediary values of the soil gradient. General results indicate that contrasting soil traits between cerrado stricto sensu and dry forest produce a strongly spatially organized and sharp transition in terms of species distribution between these physiognomies.

Resumo Embora a distribuição e a riqueza em espécies arbóreas nas fitofisionomias do Cerrado venham sendo bastante estudadas, a transição entre savanas e florestas deciduais ainda não foi abordada. Investigamos o efeito de características físico-químicas do solo sobre a distribuição de espécies arbóreas em região de contato entre cerrado sentido restrito e floresta estacional decidual (FED). As espécies arbóreas foram amostradas sistematicamente, e variáveis de topografia e características do solo foram medidas em 30 parcelas de 10×40 m, sendo 15 parcelas em cada fisionomia. A distribuição das espécies arbóreas foi espacialmente estruturada, e as características do solo diferiram entre as áreas de cerrado sentido restrito e FED, principalmente relacionadas à saturação de alumínio, saturação de bases e teores de fósforo. A saturação de alumínio aumentou em direção ao cerrado sentido restrito, enquanto a saturação de bases aumentou em direção à FED. A maioria das espécies arbóreas predominou em uma das fisionomias, como Callisthene major em cerrado sentido restrito e Anadenanthera colubrina em FED. Apenas 20% das espécies foram amplamente distribuídas em ambas as fisionomias ou, em poucos casos, restritas aos valores intermediários do gradiente de solo. Os resultados indicam um forte contraste de características do solo entre o cerrado sentido restrito e a FED, assim como uma transição acentuada e espacialmente organizada quanto à distribuição de espécies arbóreas.

Environmental variability in simultaneous selection of common bean for grain quality and mineral concentration traits

The selection of common bean (Phaseolus vulgaris L.) lines based on grain quality and mineral concentration traits will be more efficient if a minimum number of experiments is established. This study was carried out to determine whether grain quality and mineral concentration traits are significantly affected by the genotype × environment interaction; to estimate heritability and genetic gain in individual and combined experiments; and to select superior common bean lines considering a minimum number of experiments. A total of 17 common bean genotypes were evaluated in four experiments. Grain quality was determined through seven traits, and the concentration of six minerals was analyzed by acid digestion. Statistical analyses were completed using data obtained from both individual (I, II, III and IV) and combined (I and II; I, II and III; and I, II, III and IV) experiments. Except for the potassium concentration, all traits showed a significant genotype × environment interaction effect. Heritability and genetic gain estimates of grain quality and mineral concentration traits varied when the data were obtained from one or more experiments. Genetic gain may be inflated because of the data being based on one or two experiments. Four carioca bean (BRS MG Uai, LP 09-33, LEC 01-16 and Pérola) and four black bean (TB 02-19, CHP 04-239-52, TB 03-11 and IAC Netuno) genotypes were selected for their high grain quality and mineral concentration based on four experiments. Data from at least four experiments should be used to select common bean lines superior in grain quality and mineral concentration traits to increase the efficiency of simultaneous selection.

Effect of different lighting sources on the performance of broiler breeder hens

The present study aimed to evaluate the effects of using light-emitting diode (LED) lamps versus incandescent/tungsten (Inc) bulbs on broiler breeder hens' productive performance during the brooding and rearing periods (25 weeks), as well as the first 15 weeks of production. A total of 46600 one-day-old Arbor Acres Plus breeder chicks were placed in eight enclosed houses and randomly/evenly divided into two groups (four houses for each group): birds raised under yellow LED lighting, and birds raised under orange Inc lighting. Several traits have been studied to determine productive performance, including body weight at different ages, body weight gain, feed consumption, feed conversion ratio, mortality rate, uniformity, age and weight at sexual maturity, egg number, egg production rate, egg number per bird, egg weight, and egg mass. According to the findings, using LED lighting instead of Inc lighting during the rearing period resulted in a significant improvement in all studied traits, and this positive effect continued until the production period, yielding excellent results for all studied production traits. LED lighting proved to be an effective source of lighting in broiler breeders' houses.(AU)

Functional diversity: a review on freshwater fish research

Functional diversity is an emergent approach in ecology that has been applied globally to better understand the relationships between organisms and the environment. However, assessing the functional diversity of freshwater fish is a challenge for scientists. Aiming to summarize the evolution of scientific knowledge on fish functional diversity, we performed a systematic review of the literature published from 1945 to 2021 using the Web of Science. Based on the 101 articles reviewed, we found that publications about functional diversity of fishes have increased over time, mainly in Neotropical, Indomalayan and Palearctic regions. Most studies were conducted in lotic ecosystems, especially to assess environmental impacts such as biological invasions and land use. Functional diversity has been assessed mainly by morphological traits that reflect feeding and locomotion dimensions. Functional richness was the most common index used in the studies. Our findings suggest that political neglect and lack of investments may hamper the research development in several places. The missing information about the functional traits of many species may limit the use of the functional approach. We also highlight the need for the incorporation of functional diversity in conservation programs once functional diversity is a key facet of biodiversity to maintain freshwater ecosystem functioning.

A diversidade funcional tem sido avaliada principalmente através de traços funcionais morfológicos que refletem as dimensões da alimentação e locomoção. A Riqueza Funcional foi a métrica mais comumente usada nos estudos. Esses resultados sugerem que a negligência política e a falta de investimentos podem dificultar o desenvolvimento de pesquisas em diversas regiões. A falta de informações sobre os traços funcionais de muitas espécies limita o uso da abordagem funcional. Destaca-se também a necessidade de incorporar a diversidade funcional em programas de conservação, uma vez que a diversidade funcional é uma faceta chave da biodiversidade para manter o funcionamento dos ecossistemas de água doce.

Woody species distribution across a savanna-dry forest soil gradient in the Brazilian Cerrado / Distribuição de espécies arbóreas em gradiente de solo savana-floresta seca no Cerrado brasileiro

Abstract Although richness and distribution of woody species in the Cerrado physiognomies have been extensively studied, the shifts of woody species from savanna physiognomies to dry forests have not yet been addressed. Here, we investigate the effect of soil physical-chemical traits on the woody species turnover between adjacent cerrado stricto sensu and dry forest physiognomies. Woody species were surveyed, and soil and topographic variables measured, in 30 10×40 m plots systematically distributed, with 15 plots in each physiognomy. We found a spatially structured distribution of woody species, and differences of soil traits between cerrado stricto sensu and dry forest areas, mainly related to the aluminum saturation, base saturation, and available phosphorus. Aluminum saturation increased toward the savanna area, while base saturation increased toward the dry forest. Most woody species predominated in one physiognomy, such as Callisthene major in the cerrado stricto sensu and Anadenanthera colubrina in the dry forest. Only 20% of the species were widely distributed across both physiognomies or, not often, restricted to the intermediary values of the soil gradient. General results indicate that contrasting soil traits between cerrado stricto sensu and dry forest produce a strongly spatially organized and sharp transition in terms of species distribution between these physiognomies.

Resumo Embora a distribuição e a riqueza em espécies arbóreas nas fitofisionomias do Cerrado venham sendo bastante estudadas, a transição entre savanas e florestas deciduais ainda não foi abordada. Investigamos o efeito de características físico-químicas do solo sobre a distribuição de espécies arbóreas em região de contato entre cerrado sentido restrito e floresta estacional decidual (FED). As espécies arbóreas foram amostradas sistematicamente, e variáveis de topografia e características do solo foram medidas em 30 parcelas de 10×40 m, sendo 15 parcelas em cada fisionomia. A distribuição das espécies arbóreas foi espacialmente estruturada, e as características do solo diferiram entre as áreas de cerrado sentido restrito e FED, principalmente relacionadas à saturação de alumínio, saturação de bases e teores de fósforo. A saturação de alumínio aumentou em direção ao cerrado sentido restrito, enquanto a saturação de bases aumentou em direção à FED. A maioria das espécies arbóreas predominou em uma das fisionomias, como Callisthene major em cerrado sentido restrito e Anadenanthera colubrina em FED. Apenas 20% das espécies foram amplamente distribuídas em ambas as fisionomias ou, em poucos casos, restritas aos valores intermediários do gradiente de solo. Os resultados indicam um forte contraste de características do solo entre o cerrado sentido restrito e a FED, assim como uma transição acentuada e espacialmente organizada quanto à distribuição de espécies arbóreas.

Heritability and genetics correlations for body weight in escargots

The objective of this study was to estimate genetic parameters for body weight at 60 (P60), 90 (P90), and 120 (P120) days of age in escargotsof the subspecies Cornu aspersum maximum, evaluating the influence of fixed and covariable effects on these traits. The data used were collected from escargotskept in a total confinement system. The significant fixed effects and covariates for these traits were tested in a general linear model by the F-test, considering a level of significance of 5%. Both the fixed effects of box and birth year and the quadratic effect of age of weighing as a covariate were significant (p < 0.05) for P60, P90, and P120. The Restricted Maximum Likelihood (REML) methodology was used to estimate (co)variance components and genetic parameters. High heritability for P60, P90, and P120 (0.38, 0.55 and 0.78, respectively) and high genetic correlations (0.58 to 0.77) among the traits were observed. The genetic parameterscan be used as a basis for studies and practical applications to increase zootechnical indexes in this population.(AU)

Evaluation of Pelleting Mealworm (Tenebrio Molitor) Powder with Chokeberry By-product Meal To improve Duck Production and Meat Quality Traits

This study aimed to evaluate the effects of dietary supplementation pelleted Tenebrio molitor (TM) powder with chokeberry by-product (CBP) meal on duck production and meat quality traits. A total of 180 0-day-old Pekin ducks were allocated randomly between three dietary groups viz., control, Treatment 1, and Treatment 2, with three pens per group and twenty birds per pen, characterized by increasing levels of pelleted TM powder with CBP meal in concentration of 0%, 1.5%, and 3%, respectively, and reared until 42 days of age in a completely randomized design. On day 42, the ducks were sacrificed, and breast and thigh muscles were used for meat quality evaluations. Feeding pelleted TM powder with CBP meal resulted in a significant difference in final body weight, weight gain and feed conversion ratio (p<0.05). Additionally, a significant difference was observed in the pH of the breast meat samples (p<0.05). As the only significant difference between the breast and thigh meat, 1,1-diphenyl-2-picryhydrazyl radical scavenging was influenced significantly by the dietary inclusion of pelleted TM powder with CBP meal (p<0.05). However, the values of thiobarbituric acid reactive substances and meat color in both breast and thigh meat were insignificant (p>0.05) different among all groups. To conclude, the inclusion of up to 3 % of pelleted TM powder with CBP meal in the diets of ducks did improve the growth production and antioxidant characteristics effects, which could decrease TBARS and reflected by changes in 1,1-diphenyl-2- picrylhydrazyl free DPPH radical scavenging values.(AU)

Initial performance and genetic diversity of coffee trees cultivated under contrasting altitude conditions

This work evaluated the initial performance and genetic diversity of Coffea canephora genotypes cultivated in environments at contrasting altitudes. Fourteen morphophysiological traits and seven descriptors of the genus Coffea spp. of coffee trees cultivated at altitudes of 140 m and 700 m were evaluated. The design used was Federer's augmented block in a 2 × 112 factorial scheme with six blocks. The first factor was the two environments, and the second was the 112 genotypes, with eight common treatments, being five conilon coffee clones and three arabica coffee cultivars. The data were analyzed by the method of REML/BLUP and genetic correlation method. Genetic diversity was evaluated by estimating the distance matrix, applying the Gower methodology followed by the clustering method by Tocher and UPGMA. The phenotypic means were higher in the environment at an altitude of 700 m, except for plant height, number of leaves, and canopy height (CH). Genotypic effects were significant for most traits except for leaf width, CH, unit leaf area, and total leaf area. A wide genetic diversity was verified, with distances varying from 0.037 to 0.593 for the pairs of genotypes 26 × 93 and T7 × 76, respectively. Most of the traits studied showed high genotypic correlation with the environment and expressive genetic correlation between the evaluated traits thereby demonstrating the possibility of indirect selection. There is an adaptation of conilon coffee genotypes to high altitudes and the possibility of developing a specific cultivar for the southern state of Espírito Santo.

Morphometric measurements and carcass characteristics of Black Australorp, Naked Neck, and Rhode Island Red crossbreds under alternative production systems

Abstract The present trial explained the effect of alternative production systems on growth, morphometric and carcass traits of four different chicken genotypes. The second generation of two genotypes RNN (Rhode Island Red × Naked Neck) and BNN (Black Australorp × Naked Neck) obtained by two self-crosses (RNN × RNN = RR and BNN × BNN = BB) and two reciprocal crosses (RNN × BNN = RB and BNN × RNN = BR) were evaluated in three alternative production systems (conventional cages, enriched cages, and aviary). At the 6th week of age after sexing, a total of 600 birds, comprising 150 from each crossbred with a total of 300 pullets and 300 cockerels were divided into conventional cages, enriched cages, and aviary systems having 200 birds in each.Birds were organized into 3×4 factorial arrangements under Completely Randomized Design (3 production systems × 4 genotypes × 2 sexes × 25 birds = 600 birds). Regarding genotypes, RB and BR males showed higher (p 0.01) carcass yield, drumstick weight, breast weight, and thigh weight than BB and RR genotypes. Females of BR genotype showed higher (p 0.01) breast weight, thigh weight and drumstick weight. As far as production systems are concerned, higher (p 0.01) liver weight, heart weight, breast weight, intestinal weight, drumstick weight, and thigh weight were observed in the males reared in enriched cages compared with conventional cages and aviary system. Females reared in enriched cages showed higher (p 0.01) heart weight, breast weight, intestinal weight, drumstick weight, and thigh weight when compared with those reared in conventional cages and aviary. It is concluded that chickens (both sexes) of BR and RB genotypes had better morphological measurements and carcass traits than those of RR and BB genotype chickens. Among alternative production systems, chickens reared in enriched cages had better traits than those of reared in conventional cages and aviary during the growing phase.

Resumo O presente estudo explicou o efeito de sistemas alternativos de produção sobre o crescimento, características morfométricas e carcaças de quatro genótipos de frango diferentes. A segunda geração de dois genótipos RNN (Rhode Island Red × Naked Neck) e BNN (Black Australorp × Naked Neck) obtida por duas autocruzes (RNN × RNN = RR e B ANN × BNN = BB) e duas cruzes recíprocas (RNN × BNN = RB e BNN × RNN = BR) foi avaliada em três sistemas de produção alternativos (gaiolas convencionais, gaiolas enriquecidas e aviário). Na 6ª semana de idade após o sexo, um total de 600 aves, compostas por 150 de cada raça cruzada com um total de 300 pullets e 300 galos, foi dividido em gaiolas convencionais, gaiolas enriquecidas e sistemas aviários com 200 aves em cada. As aves foram organizadas em 3×4 arranjos fatoriais sob projeto completamente randomizado (3 sistemas de produção × 4 genótipos × 2 sexos × 25 aves = 600 aves). Em relação aos genótipos, os machos RB e BR apresentaram maior rendimento de carcaça (p 0,01), peso da baqueta, peso mamário e peso da coxa do que os genótipos BB e RR. As fêmeas do genótipo BR apresentaram maior (p 0,01) peso mamário, peso da coxa e peso da baqueta. No que diz respeito aos sistemas de produção, maior (p 0,01) peso hepático, peso cardíaco, peso mamário, peso intestinal, peso da baqueta e peso da coxa foram observados nos machos criados em gaiolas enriquecidas em comparação com gaiolas convencionais e sistema aviário. As fêmeas criadas em gaiolas enriquecidas apresentaram maior (p 0,01) peso cardíaco, peso mamário, peso intestinal, peso da baqueta e peso da coxa quando comparadas com as criadas em gaiolas convencionais e aviárias. Conclui-se que as galinhas (ambos os sexos) dos genótipos BR e RB apresentaram melhores medidas morfológicas e traços de carcaça do que os de frangos genótipos RR e BB. Entre os sistemas de produção alternativos, as galinhas criadas em gaiolas enriquecidas tinham características melhores do que as criadas em gaiolas convencionais e aviárias durante a fase de cultivo.

Genome-enabled prediction through quantile random forest for complex traits / Predição genômica por meio do random forest quantílitico para características complexas

Quantile Random Forest (QRF) is a non-parametric methodology that combines the advantages of Random Forest (RF) and Quantile Regression (QR). Specifically, this approach can explore non-linear functions, determining the probability distribution of a response variable and extracting information from different quantiles instead of just predicting the mean. This evaluated the performance of the QRF in the genomic prediction for complex traits (epistasis and dominance). In addition, compare the accuracies obtained with those derived from the G-BLUP. The simulation created an F2 population with 1,000 individuals and genotyped for 4,010 SNP markers. Besides, twelve traits were simulated from a model considering additive and non-additive effects, QTL (Quantitative trait loci) numbers ranging from eight to 120, and heritability of 0.3, 0.5, or 0.8. For training and validation, the 5-fold cross-validation approach was used. For each fold, the accuracies of all the proposed models were calculated: QRF in five different quantiles and three G-BLUP models (additive effect, additive and epistatic effects, additive and dominant effects). Finally, the predictive performance of these methodologies was compared. In all scenarios, the QRF accuracies were equal to or greater than the methodologies evaluated and proved to be an alternative tool to predict genetic values in complex traits.

Quantile Random Forest (QRF) é uma metodologia não paramétrica, que combina as vantagens do Random Forest (RF) e da Regressão Quantílica (QR). Especificamente, essa abordagem pode explorar funções não lineares, determinando a distribuição de probabilidade de uma variável resposta e extraindo informações de diferentes quantis em vez de apenas prever a média. O objetivo deste trabalho foi avaliar o desempenho do QRF em predizer o valor genético genômico para características com arquitetura genética não aditiva (epistasia e dominância). Adicionalmente, as acurácias obtidas foram comparadas com aquelas advindas do G-BLUP. A simulação criou uma população F2 com 1.000 indivíduos genotipados para 4.010 marcadores SNP. Além disso, doze características foram simuladas a partir de um modelo considerando efeitos aditivos e não aditivos, com número de QTL (Quantitative trait loci) variando de oito a 120 e herdabilidade de 0,3, 0,5 ou 0,8. Para treinamento e validação foi usada a abordagem da validação cruzada 5-fold. Para cada um dos folds foram calculadas as acurácias de todos os modelos propostos: QRF em cinco quantis diferentes e três modelos do G-BLUP (com efeito aditivo, aditivo e epistático, aditivo e dominante). Por fim, o desempenho preditivo dessas metodologias foi comparado. Em todos os cenários, as acurácias do QRF foram iguais ou superiores às metodologias avaliadas e mostrou ser uma ferramenta alternativa para predizer valores genéticos em características complexas.

Association of visual scores with reproductive traits in Nelore cattle using Bayesian Inference / Associação de escores visuais com características reprodutivas em bovinos Nelore utilizando Inferência Bayesiana

The use of morphological traits assessed using visual scores as indirect selection criteria in cattle has the advantage of evaluating young animals regarding potential productive and reproductive performance. This enables breeders to make earlier decisions compared to later measurements, such as scrotal circumference at 450 days (SC450) and stayability (STAY). The aim of this study was to estimate the genetic parameters for visual score traits and their associations with reproductive traits: scrotal circumference at 365 days of age (SC365), SC450, STAY, probability of precocious calving (PPC30) and age at first calving (AFC) in Nellore cattle. Visual score data from 4,175 Nellore cattle, with an average age of 22 months, and reproductive data from 3,075 cattle belonging to the HoRa Genetics Provada herd were used. The morphological traits were evaluated by the MERCOS methodology. The heritability estimates obtained ranged from 0.15 to 0.28 for visual scores and 0.10 to 0.54 for reproductive traits. Genetic correlations between visual scores and reproductive traits were generally low, except between: muscularity and PPC30; structure and STAY; racial and SC450; conformation and SC365, SC450, STAY, and AFC; navel and STAY and AFC; and sacrum and SC365, STAY, and AFC, which were moderate to high. The identification of animals with flat sacral bone (not protruding or sloping) can also be an efficient characteristic in the identification for early pregnancy, and together with the musculature score, they can be related to animals with lower age at the first calving.(AU)

A utilização de características morfológicas de bovinos, pelo uso de escores visuais como critério de seleção indireta tem como vantagem a avaliação em animais jovens quanto ao potencial desempenho produtivo e reprodutivo, antecipando a tomada de decisão em comparação a medidas tomadas de forma tardia, como perímetro escrotal aos 450 dias (PE450) e stayability (STAY). Objetivou-se estimar os parâmetros genéticos para características de escores visuais e a associação dessas com características reprodutivas, perímetro escrotal aos 365 (PE365) dias de idade, PE450, STAY, probabilidade de parto precoce (3P) e idade ao primeiro parto (IPP) em bovinos Nelore. Foram utilizadas informações de escores visuais e de reprodução de 4.175 e 3.075 bovinos, respectivamente, com idade média de 22 meses, pertencentes a fazenda HoRa Genética Provada. As características morfológicas foram avaliadas pela metodologia MERCOS. As estimativas de herdabilidade obtidas apresentam grande amplitude, variando de 0,15 a 0,28 para escores visuais e 0,10 a 0,54 para características reprodutivas. As correlações genéticas entre característica de escores visuais e reprodução foram, de maneira geral baixas (0.03-0.66), com exceção entre a musculosidade e 3P, estrutura e STAY, racial e PE450, conformação com PE365, PE450, STAY e IPP, ônfalo com STAY e IPP, e sacro com PE365, STAY e IPP, que foram moderadas a altas. A identificação de animais com melhor osso sacro (mesmo nível das ancas), ou seja, não saliente ou inclinado pode ser uma característica eficiente na identificação para prenhez precoce, e juntamente ao escore de musculatura poderão ser relacionados a animais com menor idade ao primeiro parto.(AU)

Sex and slaughter weight on carcass traits and non-carcass components of horses / Sexo e peso de abate sobre as características de carcaça e componentes não-carcaça de cavalos

ABSTRACT: The study evaluated the effect of sex and slaughter weight on carcass traits and non-carcass components of 1,489 horses (739 geldings and 750 females, classified into eight groups according to their weight). Data were analyzed under a completely randomized design. Geldings had a higher (P < 0.05) hot carcass yield (HCY) and cold carcass yield (CCY) than females; however, fat yellowness values (b*) were greater (P < 0.05) in females. Slaughter weight (SW) affected the carcass characteristics. Hot carcass weight (HCW), cold carcass weight (CCW), HCY, and CCY increased (P < 0.05) in accordance with slaughter weight, while cool loss percentage (CL%) was lower (P < 0.05) in horses weighing more than 300 kg. In addition, the non-carcass components decreased (P < 0.05) as the weight of the horses increased. In conclusion, sex and body weight are factors to consider in the production of equine meat since they affect carcass characteristics and non-carcass components.

RESUMO: O estudo teve como objetivo avaliar o efeito do sexo e do peso ao abate sobre as características de carcaça e componentes não-carcaça de 1.489 cavalos (739 machos castrados e 750 fêmeas, classificados em oito grupos de acordo com o peso). Os dados foram analisados em um desenho inteiramente casualizado. Os semeadores apresentaram maior rendimento de carcaça quente (HCY) e fria (CCY) do que as fêmeas, porém o amarelecimento da gordura (b*) foi maior nas fêmeas. O peso ao abate (SW) afetou as características de carcaça. HCW, CCW, HCY e CCY aumentaram de acordo com o peso de abate, enquanto CL% foi menor em equinos com peso superior a 300 kg. Além disso, os componentes não-carcaça diminuíram com o aumento do peso dos cavalos. Em conclusão, sexo e peso corporal são fatores a serem considerados na produção de carne equina, uma vez que afetam as características da carcaça e seus componentes.