Estimation of repeatability and genotypic superiority of elephant grass half-sib families for energy purposes using mixed models

The mixed-model methodology is an alternative to select genotypes for traits highly influenced by the environment. In addition, this method allows FOR estimating the repeatability coefficient and predicting the number of assessments needed for a selection process to increase reliability. This study aimed to determine the minimum number of evaluations necessary for a reliable selection process and to estimate the variance components used for predicting genetic gains between and within half-sib families of elephant grass ( Cenchrus purpureus (Schumach.) Morrone ) using the mixed-model methodology. Half-sib families were generated using genotypes from the Active Germplasm Bank of Elephant Grass. The experiment was performed in a randomized block design with nine half-sib families, three replicates, and eight plants per plot. We evaluated 216 genotypes (individual plants) of elephant grass. The deviance analysis was carried out, genetic parameters were estimated, gains between and within families were predicted, and repeatability coefficients were obtained using Selegen software. There was genetic variability for selection within the families evaluated. The reliability values found above 60 % for plant height and number of tillers and above 80 % for dry matter yield suggest that only two evaluations are required to select superior genotypes with outstanding reliability. Sixteen genotypes were identified and selected for their productive potential, which can be used as parents in elephant grass breeding programs for bioenergy production.(AU)

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.

Variation in patterns of fish assemblage and their environmental correlates in a tropical river basin from the Gulf of Mexico slope

Understanding patterns of freshwater fish assemblage structure is key to protect them from ongoing human-induced threats to aquatic biodiversity. Yet, studies on associations between fish assemblages and habitat are lacking from many areas of high diversity in Middle America. We assessed fish assemblage structure and environmental associations from a portion of the Lacantún River sub-basin (Usumacinta River, Chiapas, Mexico). Based on environmental data and 17,462 individuals (56 species, 46 genera, and 22 families) captured from 13 sites sampled between 2017­2019, we found that stream order, distance to the Usumacinta, forest cover, temperature, and dissolved oxygen are key to explaining assemblage composition. Four clusters were found via multivariate regression tree analysis, with stream order and dissolved oxygen as defining variables. Our findings suggest that fish communities remain spatially structured even at small scales, in association to environmental gradients among habitats.(AU)

Comprender los patrones de estructuración en los ensamblajes de peces dulceacuícolas es una clave para protegerlos de las amenazas humanas a la biodiversidad acuática. No obstante, los estudios sobre asociaciones entre ensamblajes de peces y su hábitat son aún escasos en muchas áreas de alta diversidad de América Media. Evaluamos las asociaciones entre la estructura de los ensamblajes de peces y el ambiente de una porción de la subcuenca del Río Lacantún (cuenca del Río Usumacinta, Chiapas, México). Con base en datos ambientales y un total de 17,462 individuos (56 especies, 46 géneros, y 22 familias) capturados de 13 sitios muestreados entre 2017­2019, encontramos que el orden del cauce, distancia al Usumacinta, cobertura vegetal, temperatura y oxígeno disuelto son clave para explicar la composición de los ensamblajes. Cuatro grupos se detectaron utilizando un árbol de regresión multivariada, definidos por el orden del cauce y el oxígeno disuelto como variables definitorias. Nuestros hallazgos sugieren que las comunidades de peces retienen su estructura espacial aún a pequeñas escalas, en asociación a gradientes ambientales entre hábitats.(AU)

Transcriptome analysis of the spider Phonotimpus pennimani reveals novel toxin transcripts

Background: Phonotimpus pennimani (Araneae, Phrurolithidae) is a small-sized (3-5 mm) spider endemic to the Tacaná volcano in Chiapas, Mexico, where it is found in soil litter of cloud forests and coffee plantations. Its venom composition has so far not been investigated, partly because it is not a species of medical significance. However, it does have an important impact on the arthropod populations of its natural habitat. Methods: Specimens were collected in Southeastern Mexico (Chiapas) and identified taxonomically by morphological characteristics. A partial sequence from the mitochondrial gene coxI was amplified. Sequencing on the Illumina platform of a transcriptome library constructed from 12 adult specimens revealed 25 toxin or toxinlike genes. Transcripts were validated (RT-qPCR) by assessing the differential expression of the toxin-like PpenTox1 transcript and normalising with housekeeping genes. Results: Analysis of the coxI-gene revealed a similarity to other species of the family Phrurolithidae. Transcriptome analysis also revealed similarity with venom components of species from the families Ctenidae, Lycosidae, and Sicariidae. Expression of the toxinlike PpenTox1 gene was different for each developmental stage (juvenile or adult) and also for both sexes (female or male). Additionally, a partial sequence was obtained for the toxin-like PpenTox1 from DNA. Conclusion: Data from the amplification of the mitochondrial coxI gene confirmed that P. pennimani belongs to the family Phrurolithidae. New genes and transcripts coding for venom components were identified.(AU)

Detection of adaptive genetic diversity and chemical composition in date palm cultivars and their implications in controlling red palm weevil, Rhynchophorus ferrugineus Oliver / Detecção da diversidade genética adaptativa e composição química em cultivares de tamareira e implicações no controle do bicudo vermelho da palmeira, Rhynchophorus ferrugineus Oliver

This study, about RPW and date palms, is under the scope of date palm bioecology and nutrition (nutritional ecology) which includes the integration of several areas of research such as date palm biochemistry, genetics, and RPW infestation behavior through various date palm cultivars. Date palm (Phoenix dactylifera L.; Arecaceae) production is under threat from the red palm weevil (RPW), Rhynchophorus ferrugineus Oliver. A better understanding of genetic diversity within date palm cultivars can be useful for its implementation within the insect IPM program in the future. Three indices, namely simple-sequence repeats (SSR) markers to elucidate genetic diversity, chemical components, and a natural infestation index of RPW, were used to evaluate the resistant or susceptible date palm cultivars in Qassim. Based on a field survey of RPW infestation within 79 date palm farms involving 11 cultivars at Qassim, the sensitivity and resistance cultivars were determined. The resistant date palm cultivars were Nabtat Ali, Shakrah, red Sukary, and um Kobar which had the lowest degree of RPW abundance %. Values of the essential minerals, nitrogen, phosphorus, potassium, and calcium within the date palm cultivars were also estimated. RPW abundance % was negatively correlated with the calcium content of date palm cultivars. The principal component analysis (PCA) revealed that the calcium content and RPW abundance % were highly affected by the cultivars. SSR markers of the date palm cluster tree divided genotypes into two main groups at similarity coefficients between 0.56 and 0.91. The 1st group included; Nabtet Ali, Red Sukary, Um Kobar, and Shakrah with similarity coefficients between 0.56, this group was the most resistant cultivars. Therefore, SSR markers were able to characterize and resolve genetic diversity in date palm cultivars for RPW resistance. When SSR markers coupled with higher calcium (Ca) content can efficiently replace indices in characterizing resistant date-palm genotypes with a high confidence level. Integration between date palm genetic diversity, chemical structures, and RPW infestations rates promoted the understanding of the interplay between the diversity of RPW management (short-time scale), and the resistance genes, plant nutrition, and dynamics of the diversity of RPW through domestication and diversification (long-timescale). Therefore, our results may lead to a change in RPW control strategies by switching to using safe alternative pesticide control methods (Resistant cultivars of date palm), which are underestimated and may reveal the impact of low-cost, but highly effective agricultural practices in the field of date production in the world. Understanding the genetic structure and calcium content of date palm cultivars mechanisms could help to predict date palm resistance against RPW populations in the new IPM strategy in RPW control.

Este estudo, sobre RPW e tamareiras, está no âmbito da bioecologia e nutrição da tamareira (ecologia nutricional) que inclui a integração de várias áreas de pesquisa, como bioquímica da tamareira, genética e comportamento de infestação de RPW através de vários cultivares de tamareira. A produção da tamareira (Phoenix dactylifera L.; Arecaceae) está ameaçada pelo gorgulho vermelho da palmeira (RPW), Rhynchophorus ferrugineus Oliver. A compreensão mais aprofundada da diversidade genética dentro dos cultivares de tamareiras pode ser útil para sua implementação no futuro programa de MIP de insetos. Três índices, ou seja, marcadores de sequência simples (SSR) para elucidar a diversidade genética, componentes químicos e um índice de infestação natural de RPW, foram utilizados para avaliar as cultivares de tamareiras resistentes ou suscetíveis em Qassim. Com base em uma pesquisa de campo da infestação de RPW em 79 fazendas de tamareiras envolvendo 11 cultivares em Qassim, as cultivares de sensibilidade e resistência foram determinadas. As cultivares de tamareiras resistentes foram Nabtat Ali, Shakrah, red Sukary e um Kobar, que apresentaram o menor grau de abundância de RPW. Também foram estimados os valores dos minerais essenciais, nitrogênio, fósforo, potássio e cálcio nas cultivares de tamareira. A porcentagem de abundância de RPW correlacionou-se negativamente com o teor de cálcio das cultivares de tamareira. A análise de componentes principais (PCA) revelou que o teor de cálcio e a abundância de RPW % foram altamente afetados pelas cultivares. Marcadores SSR da tamareira dividiram os genótipos em dois grupos principais com coeficientes de similaridade entre 0,56 e 0,91. O 1º grupo incluiu; Nabtet Ali, Red Sukary, Um Kobar e Shakrah com coeficientes de similaridade entre 0,56, este grupo foi o de cultivares mais resistentes. Portanto, os marcadores SSR foram capazes de caracterizar e resolver a diversidade genética em cultivares de tamareiras para resistência a RPW. Quando os marcadores SSR associados ao maior teor de cálcio (Ca) podem substituir com eficiência os índices na caracterização de genótipos de tamareiras resistentes com alto nível de confiança. A integração entre diversidade genética da tamareira, estruturas químicas e taxas de infestação de RPW promoveu a compreensão da interação entre a diversidade de manejo de RPW (escala de tempo curto) e os genes de resistência, nutrição de plantas e dinâmica da diversidade de RPW por meio da domesticação e diversificação (longo prazo). Portanto, nossos resultados podem levar a uma mudança nas estratégias de controle de RPW, passando a usar métodos alternativos seguros de controle de pesticidas (cultivares resistentes de tamareira), sendo subestimados e podem revelar o impacto de práticas agrícolas de baixo custo, mas altamente eficazes no campo de produção de tâmaras no mundo. Compreender a estrutura genética e o teor de cálcio dos mecanismos dos cultivares de tamareira pode ajudar a prever a resistência da tamareira contra populações de RPW na nova estratégia de IPM no controle de RPW.

Mapping of leaf rust resistance genes in common wheat 'Guinong08-6' / Mapa de genes de resistência à ferrugem da folha em trigo 'Guinong08-6'

Wheat leaf rust (Puccinia triticina Eriks.), a devastating disease of wheat in the world, causes severe yield losses and therefore the development of resistant cultivars is very important. Here, a Chinese wheat line (Guinong08-6) showed adult-plant resistance against mixed fungal isolates of leaf rust, which is common in Guiyang region. It was crossed with a susceptible wheat line (Guinong19) to develop F1, F2, and F3 hybrids. Combined SSR and STS markers were used to map leaf rust resistance genes in Guinong08-6, and the resistance phenotype of Guinong08-6 was co-regulated by two complementary dominant genes, named LrGn08-6A and LrGn08-6B. LrGn08-6A was mapped to chromosome 2AS with markers URIC-LN2 and Xgpw2204, which flanked the gene at distances of 1.8 centimorgan (cM) and 14.83 cM, respectively. LrGn08-6B was mapped to chromosome 4DL with markers Xgpw342 and Xbarc93, which both flanked the gene at a distance of 26.57 cM. Genetic and molecular marker analyses demonstrated that LrGn08-6A, which was inherited from Aegilops ventricosa may be the resistance gene Lr37, while LrGn08-6B may be a newly discovered leaf rust resistance gene.(AU)

A ferrugem da folha do trigo (Puccinia triticina Eriks.), importante doença do trigo em todo o mundo, causa graves perdas de rendimento e, portanto, o desenvolvimento de cultivares resistentes é muito importante. Nesta pesquisa, uma linhagem chinesa de trigo (Guinong08-6) mostrou resistência de plantas adultas a uma mistura de isolados do patógeno, na região de Guiyang, China. Essa linhagem foi cruzada com uma linhagem suscetível de trigo (Guinong19) para desenvolver híbridos F1, F2 e F3. Combinados de marcadores SSR e STS foram usados para mapear genes de resistência à ferrugem da folha em Guinong08-6, e o fenótipo de resistência de Guinong08-6 foi co-regulado por dois genes dominantes complementares, chamados LrGn08-6A e LrGn08-6B. LrGn08-6A foi mapeado para o cromossomo 2AS com marcadores URIC-LN2 e Xgpw2204, que flanquearam o gene em distâncias de 1,8 centimorgano (cM) e 14,83 cM, respectivamente. LrGn08-6B foi mapeado para o cromossomo 4DL com marcadores Xgpw342 e Xbarc93, e ambos flanquearam o gene a uma distância de 26,57 cM. As análises genéticas e moleculares de marcadores demonstraram que LrGn08-6A, que foi herdado de Aegilops ventricosa, pode ser o gene de resistência Lr37, enquanto LrGn08-6B pode ser um gene recentemente descoberto de resistência à ferrugem da folha do trigo.(AU)

Identification of Polymorphism in the MC1R Gene and Its Association with the Melanin Content in Feathers of Chinese Yellow Quails

MC1R plays a crucial role in controlling the type of melanin synthesized in the melanocytes, which greatly affects plumage color in birds. One g.16796362G/T SNP was found in the MC1R gene coding region, which caused a Met120Ile mutation in the amino acid sequence. The Met120Ile mutation was located in the third transmembrane domain of the MC1R protein and decreased protein stability. The g.16796362G/T locus achieved medium polymorphism and had significant association with feather melanin content in Chinese yellow quails. The contents of total melanin and pheomelanin with AA genotype were significant lower than those with AB or BB genotypes in skin tissues, while the expression levels of MC1R mRNA had no significant difference in feathers with different genotypes. This experiment indicated that the Met120Ile mutation could affect the function of the MC1R protein and change the biosynthesis of melanin in Chinese yellow quails.(AU)

Insect meal in poultry feed: a potential protein source

The present study aims to conduct a review on the potential use of insect meal as an alternative protein source in poultry feed, particularly to serve the rearing of free-range chickens. Insects are already part of the diet of birds in their natural habitat, and the availability of low-cost alternative foods with low environmental impact is essential for the development of the activity. The review comprehended studies that used meals consisting of silkworm (Bombyx mori) chrysalis, earthworm (Eisenia foetida), housefly (Musca domestica), black soldier fly (Hermetia illucens) and mealworm beetle (Tenebrio molitor) to replace plant-based protein sources. In general, insect meals have a high content of crude protein and ether extract, as well as an essential amino acid profile suitable for poultry feeding. The addition of insect meal in poultry feed normally shows good results as to growth performance and egg production, without causing a negative effect on carcass characteristics, meat sensory quality and egg quality, presenting itself as an alternative protein source with good prospects for replacing plant-based sources in poultry feed.(AU)

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.

A proposed new frame score system for Nellore cattle / Proposta de novo sistema de escore de estrutura corporal para bovinos Nelore

A new frame score system was developed for Nellore cattle, based upon ideal slaughter weights to achieve desired degrees of carcass fat cover. Data consisting of 688 complete records including sex, age, weight, hip height, and subcutaneous fat on growing Nellore cattle (190 males and 498 females) were obtained from the National Association of Breeders and Researchers (ANCP), Ribeirão Preto - SP, Brazil. Weight data were regressed on sex, age, hip height, and fat cover as covariates. Age was then fixed at 550 days and fat cover was set to 6 mm, and new equations for frame scores (1 to 11) in Nellore cattle were developed: FrameNellore (males) = -42.43 + 0.04919 × Age + 0.3368 × Height - 0.0003369 × Age × Height and FrameNellore (females) = -41.76 + 0.04919 × Age + 0.3368 × Height - 0.0003369 × Age × Height (Age and Height in days and cm, respectively). The Nellore equations resulted in average frame of 5.3, ranging from 2.3 to 7.7. Values were similar for males (5.4) and females (5.3). By contrast, previous equations gave higher values, that were very different between males and females. The new Nellore frame scores appear reasonable, particularly regarding body composition.(AU)

Um novo sistema de escore para estrutura corporal foi desenvolvido para bovinos Nelore, baseado em pesos de abate ideais para atingir os graus desejados de cobertura de gordura da carcaça. Dados de 688 registros completos incluindo sexo, idade, peso, altura do quadril e gordura subcutânea de bovinos Nelore em crescimento (190 machos e 498 fêmeas) foram obtidos da Associação Nacional de Criadores e Pesquisadores (ANCP), Ribeirão Preto - SP, Brasil. Os dados de peso foram regredidos por sexo, idade, altura do quadril e cobertura de gordura como covariáveis. A idade foi então fixada em 550 dias e a cobertura de gordura foi fixada em 6 mm, e novas equações para escores de estrutura corporal (1 a 11) em bovinos Nelore foram desenvolvidas: FrameNelore (machos) = -42,43 + 0,04919 × Idade + 0,3368 × Altura - 0,0003369 × Idade × Altura e FrameNellore (fêmeas) = -41,76 + 0,04919 × Idade + 0,3368 × Altura - 0,0003369 × Idade × Altura (Idade e Altura em dias e cm, respectivamente). As equações de Nelore resultaram em estrutura corporal médio de 5,3, variando de 2,3 a 7,7. Os valores foram semelhantes para machos (5,4) e fêmeas (5,3). Por outro lado, as equações anteriores deram valores mais altos, que eram muito diferentes entre machos e fêmeas. As novas pontuações de estruturacorporal no Nelore parecem razoáveis, principalmente em relação à composição corporal.(AU)

Heterozygosity as a factor of increasing the meat productivity of kalmyk steers / Heterozigosidade como fator de aumento da produtividade da carne de bois kalmyk

The present work carried out full-genome SNP genotyping of 16-month-old Kalmyk steers to study their productive characteristics and beef quality indicators in the leading farms of the Republic of Kalmykia (Group I was located at the Agrofirma Aduchi farm; Group II at the Kirovsky breeding plant, and Group III at the Plodovitoye agricultural cooperative). As a result of investigating the frequencies of some homozygous alleles, the study established that the heterozygous allele A/A varied considerably along the lines from 0.2785 to 0.3146, while B/B varied from 0.3697 to 0.4125. Meanwhile, the heterozygous allele A/B varied from 0.2986 to 0.3197. Estimated inbreeding coefficients were 1.35, 1.28 and 1.27%. The conducted studies established a higher natural resistance determined by lysozyme, bactericidal and phagocytic activities of steers raised at the Agrofirma Aduchi as farm than their counterparts at the other agricultural enterprises. Over the entire period of the experiment, the steers from 8 to 16 months of age in Group I exceeded the indices of their counterparts in Groups II and III by 30.46g, or 3.31% and 38.04g, or 4.16%, respectively. It is concluded that an increase in the heterozygosity of the studied Kalmyk steers not only results in higher meat productivity, but also improves the quality of carcass and beef quality, increases the yield of more valuable meat grades, and optimizes the fractional composition of proteins.

O presente trabalho realizou a genotipagem de bois Kalmyk de 16 meses de idade para estudar suas características produtivas e indicadores de qualidade da carne bovina nas principais fazendas da República de Kalmykia (o Grupo I estava localizado na fazenda Agrofirma Aduchi; Grupo II - na planta de criação Kirovsky; Grupo III - na cooperativa agrícola Plodovitoye). Como resultado da investigação das freqüências de alguns alelos homozigotos, o estudo estabeleceu que o alelo heterozigotos A/A variou consideravelmente de 0,2785 a 0,3146, enquanto o B/B variou de 0,3697 a 0,4125. Enquanto isso, o alelo heterozigoto A/B variou de 0,2986 a 0,3197. Os coeficientes estimados de consanguinidade foram de 1,35, 1,28 e 1,27%. Os estudos realizados estabeleceram uma maior resistência natural determinada pelas atividades lisozóides, bactericidas e fagocitárias dos bois criados na Agrofirma Aduchi como fazenda do que suas contrapartes nas outras empresas agrícolas. Durante todo o período do experimento, os bois de 8 a 16 meses de idade no Grupo I excederam os índices de suas contrapartes nos Grupos II e III em 30,46g, ou 3,31% e 38,04g, ou 4,16%, respectivamente. Conclui-se que um aumento na heterozigosidade dos bois Kalmyk estudados não só resulta em maior produtividade da carne, mas também melhora a qualidade da carcaça e da carne bovina, aumenta o rendimento das carnes de maior valor e otimiza a composição fracionária das proteínas.

Association of Kappa casein gene polymorphism with milk production traits in crossbred dairy cows / Associação do polimorfismo do gene Kappa-caseína com características de produção de leite em vacas leiteiras mestiças

Milk's qualitative and technological properties are greatly affected by genetic polymorphisms in the kappa-casein gene, and their polymorphisms may serve as informative markers of yield and composition. Thus, the objective of this study was to detect kappa-casein (kappa-CN) gene polymorphisms and their association with milk production traits in crossbred dairy cows. One hundred healthy crossbred (Friesian x Jenoubi) dairy animals between three and five years old were sampled for blood and milk during their first lactation. The genomic DNA was extracted from whole blood, and restriction fragment length polymorphism (RFLP-PCR) was used to determine the genotype of the kappa-CN gene. As a consequence of the restriction digestion of this fragment with Hind III, it showed three different restriction patterns: BB (453 base pairs uncut), AB (453, 206, and 225 base pairs), and AA (206 and 225 base pairs). Based on genetic diversity, the AB genotype was the most predominant (n = 67), with a frequency of 0.67. A variant genotype of the kappa-CN gene was associated with milk production traits in crossbred dairy cows. Animals with the AA variant produced a higher milk yield and a higher percentage of fat, casein, protein, and solids not fat (SNF) (P≤0.05) (1.397kg, 0.75%, 0.31%, 0.27%, and 0.68%, respectively) than those with the BB variant. A logistic regression analysis confirmed that the kappa-CN genotypes increase milk yield and casein content. Therefore, genetic variants of the kappa-CN gene could be used as genetic markers for improving milk production traits in dairy cattle.(AU)

As propriedades qualitativas e tecnológicas do leite são muito afetadas por polimorfismos genéticos no gene kappa-caseína e esses polimorfismos podem servir como marcadores informativos de rendimento e composição. Assim, o objetivo deste estudo foi detectar polimorfismos do gene kappa-caseína (kappa-CN) e sua associação com características de produção de leite em vacas leiteiras mestiças. Cem animais mestiços (Freisian x Jenoubi) saudáveis, entre três e cinco anos de idade, foram amostrados durante a primeira lactação para sangue e leite. O DNA genômico foi extraído do sangue total e o polimorfismo dos fragmentos de restrição do DNA genômico (RFLP-PCR) foi usado para determinar o genótipo do gene kappa-CN. Em consequência da digestão de restrição deste fragmento com Hind III, ele apresentou três padrões de restrição diferentes: BB (453 pares de bases não cortadas), AB (453,206 e 225 pares de bases) eAA (206 e 225 pares de bases). Com base na diversidade genética, o genótipo AB foi o mais predominante (n = 67), com frequência de 0,67. Genótipo variante do gene kappa-CN foi associado com características de produção de leite em vacas leiteiras mestiças. Animais com a variante AA tiveram maior produção de leite e maior percentual de gordura, caseína, proteína e sólidos não gordurosos (SNG) (P≤0,05) (l,397kg, 0,75%, 0,31%, 0,27% e 0,68%, respectivamente) do que aqueles com variante BB. Uma análise de regressão logística confirmou que os genótipos kappa-CN aumentam a produção de leite e o teor de caseína. Portanto, variantes genéticas do gene kappa-CN podem ser usadas como marcadores genéticos para melhorar as características de produção de leite em bovinos leiteiros.(AU)

Composição de cana-de-açúcar para alimentação animal em função da aplicação de bactérias diazotróficas / Composition of sugarcane for animal feeding with the application of diazotrophic bacteria

A cana-de-açúcar pode ser empregada na alimentação animal devido ao seu alto rendimento de matéria seca. No entanto, há muitas recomendações para evitar o emprego como alimento para animais de bom potencial genético, pois apresenta baixo teor proteico e de minerais, bem como e fibra de baixa qualidade. Desta forma, o objetivo deste trabalho foi avaliar os efeitos da aplicação de uma mistura de cinco bactérias diazotróficas (Gluconacetobacter diazotrophicus; Herbaspirillum seropedicae; Herbaspirillum rubrisubalbicans; Paraburkholderia tropica; Nitrospirillum amazonense) e da adubação nitrogenada sobre a produção, maturação e composição químico-bromatológica de cinco variedades de cana-de-açúcar com potencial para serem empregadas na alimentação animal. Os tratamentos foram formados conforme a combinação dos cinco genótipos de cana-de-açúcar (RB867515, RB966928, RB106814, RB106818 e RB106819) com quatro condições de inoculação e adubação nitrogenada em cobertura. Os teores de sólidos solúveis totais foram determinados dos 180 dias após o transplante até a colheita do experimento, onde foi avaliada a produtividade e a amostragem de material foi coletada para as avaliações químico-bromatológicas: matéria seca, nitrogênio acumulado, proteína bruta, fibra em detergente neutro, fibra em detergente ácido, holocelulose, celulose, hemicelulose, lignina, extrativos totais e cinzas. De acordo com os resultados deste estudo, conclui-se que a aplicação de bactérias diazotróficas de forma isolada ou em conjunto com a adubação nitrogenada, aumenta a produtividade e os sólidos solúveis totais, antecipando a maturação, além de melhorar a composição químico-bromatológica das plantas de cana-de-açúcar.

Sugarcane can be used in animal feed due to its high dry matter yield. However, there are many recommendations to avoid its use as food for animals with good genetic potential, since it has a low contents of protein and minerals, as well as fiber of low quality. Therefore, this work aimed to evaluate the effects of applying a mixture of five diazotrophic bacteria (Gluconacetobacter diazotrophicus; Herbaspirillum seropedicae; Herbaspirillum rubrisubalbicans; Paraburkholderia tropica; Nitrospirillum amazonense) and nitrogen fertilization on the production, maturation, and chemical-bromatological composition of five sugarcane varieties with potential to be used in animal feed. The treatments were formed according to the combination of the five sugarcane genotypes (RB867515, RB966928, RB106814, RB106818, and RB106819) with four conditions of inoculation and nitrogen fertilization in coverage. The levels of total soluble solids were determined from 180 days after transplantation until the harvest of the experiment, where productivity was evaluated and the sample material was collected for chemical-bromatological evaluations: dry matter, accumulated nitrogen, crude protein, neutral detergent fiber, acid detergent fiber, holocellulose, cellulose, hemicellulose, lignin, total extracts, and ashes. According to the results of the present study, it is concluded that the application of diazotrophic bacteria alone or in conjunction with nitrogen fertilization, increases productivity and total soluble solids, anticipating maturation, in addition to improving the chemical-bromatological composition of sugarcane plants.

DGAT and LEP gene polymorphisms and their association with carcass characteristics and the lipid profile of meat from Nellore cattle / Polimorfismo dos genes DGAT e LEP e sua associação com características de carcaça e perfil lipídico da carne de bovinos nelore

The objective of this study was to evaluate the association of polymorphisms in the diacylglycerol acyltransferase (DGAT) and leptin (LEP) genes with the performance, carcass characteristics, meat quality, and lipid profile of Nellore cattle. A total of 100 intact male Nelore cattle were used to analyze the performance, carcass, physicochemical and centesimal composition, and fatty acid profile of beef. To identify the polymorphisms, the PCR­single-strand conformation polymorphism (SSCP) technique was applied to genomic DNA extracted from muscle tissue. The SSCP technique revealed the presence of four band patterns for the DGAT gene (AC, AD, AE and BB) with five alleles (A, B, C, D and E). For the LEP gene, five band patterns (AA, AB, AC, BB and BC) with three alleles (A, B and C) were observed. For the LEP gene, the AB genotype was associated with higher backfat thickness and ribs weight, while the BB genotype was associated with lower ribs yield; higher hindquarter yield was associated with AC and BB genotypes. Higher contents of C17:0, C18:0 and lower contents of C18:2ω6C, total polyunsaturated fatty acids, total ω6 and ratio of polyunsaturated and saturated fatty acids (PUFA/SFA) were verified for the AC genotype of the LEP gene. The AC and AA genotypes of the LEP gene were associated with higher means of C15:0 and C18:1ω9t. For the DGAT gene, the highest C24:0 content was associated with the AE genotype and the lowest with the AD and BB genotypes. Polymorphisms in the DGAT and LEP genes influence carcass parameters and the lipid profile of the meat of Nellore cattle.

Objetivou-se com este estudo avaliar a associação do polimorfismo dos genes da Diacilglicerol Aciltransferase (DGAT) e Leptina ­ (LEP) em relação ao desempenho, características de carcaça, qualidade de carne e perfil lipídico de bovinos Nelore. Para o estudo, foram utilizados um total de 100 bovinos nelores machos inteiros e avaliado os parâmetros de desempenho, composição da carcaça, composição físico-química, centesimal e perfil lipídico da carne. Para identificação dos polimorfismos foi utilizada a técnica de PCR-SSCP a partir da extração do DNA genômico do tecido muscular. A técnica de SSCP revelou a presença de quatro padrões de banda para o gene DGAT (AC, AD, AE e BB) com cinco alelos (A, B, C, D e E) e, para o gene LEP foram verificados cinco padrões de bandas (AA, AB, AC, BB e BC) com três alelos (A, B e C). Para o gene LEP, o genótipo AB foi associado a maior espessura de gordura subcutânea e peso do corte ponta de agulha, enquanto o genótipo BB foi associado a menor rendimento do corte ponta de agulha; maior rendimento do corte traseiro foi associado aos genótipos AC e BB. Maiores teores de C17:0, C18:0 e menores de C18: 2ω6C, total de ácidos graxos poli-insaturados, total de ω6 e a relação de ácidos graxos poli-insaturados e saturados (POL/SAT) foram verificados para o genótipo AC do gene LEP. Os genótipos AC e AA do gene LEP foram associados a maiores médias de C15:0 e C18:1ω9t. Para o gene DGAT, os maiores teores de C24:0 foram associados o genótipo AE e o menores aos genótipos AD e BB. A ocorrência de polimorfismo nos genes DGAT e LEP revelaram influência destes sobre parâmetros de carcaça e perfil lipídico da carne de bovinos Nelore.

Refrigeração de sêmen canino em meio diluente à base de água de coco (Cocos nucifera) natural / Canine semen refrigeration in a natural coconut water (Cocos nucifera)-based extender / Refrigeración de semen canino en un medio diluyente natural a base de agua de coco (Cocos nucifera)

A inseminação artificial em cadelas contribui para o melhoramento genético da espécie, previne algumas doenças sexualmente transmissíveis a partir da cópula e possibilita a reprodução de animais que não poderiam copular de forma natural, seja por motivos anatômicos, geográficos ou comportamentais. Todavia, nem sempre é possível utilizar o sêmen fresco, sendo assim necessário um diluente para resfriar e mantê-lo viável por determinado período. Diante disso, o objetivo com este trabalho foi analisar o sêmen canino diluído em água de coco e refrigerado, à 5 ºC em diferentes tempos. Foram utilizados cinco cães da raça Hounds do Brasil, realizando três colheitas de sêmen de cada animal, com intervalos de sete dias. Os ejaculados foram mantidos a temperatura de 37ºC e realizado análises macroscópicas (volume, cor, aspecto e odor) e microscópicas (motilidade, vigor, concentração e morfologia espermática). Em seguida, os ejaculados foram diluídos em água de coco natural a uma concentração de 200 milhões de espermatozoides/mL, e mantidos à temperatura de 5 °C, por até 72 horas. Nos intervalos de seis, doze, vinte e quatro, trinta e seis, quarenta e oito, e setenta e duas horas, as amostras foram avaliadas quanto a motilidade e vigor espermático. Os ejaculados frescos apresentaram em média volume de 6,2 mL, cor branca, aspecto aquoso a leitoso, odor "sui generis", motilidade espermática de 89,5 %, vigor espermático 4,3, concentração média de 418 x106espermatozoides/mL e 7,3% de alterações patológicas. Após o início do resfriamento à 5 ºC, os valores de motilidade e vigor diminuíram com o passar do tempo, sendo os menores valores encontrados após 48 e 72 horas. O diluente a água de coco in natura mostrou-se eficiente para refrigeração de sêmen canino, à 5 ºC, conservando-o por um período de até 36h após a colheita, conforme preconizado pelo Colégio Brasileiro de Reprodução Animal.(AU)

improvement of the species, prevents some sexually transmitted diseases through copulation and allows the reproduction of animals that could not copulate naturally, either for anatomical, geographic or behavioral reasons. However, it is not always possible to use fresh semen, thus requiring a diluent to cool and keep it viable for a certain period. Therefore, the objective of this work was to analyze canine semen diluted in coconut water and refrigerated at 5 ºC at different times. Five Brazilian Hounds were used, performing three semen collections from each animal, with intervals of seven days. The ejaculates were kept at a temperature of 37 ºC and macroscopic (volume, color, appearance and odor) and microscopic (motility, vigor, concentration and sperm morphology) analyzes were performed. Then, the ejaculates were diluted in natural coconut water at a concentration of 200 million sperm/mL, and kept at a temperature of 5 °C for up to 72 hours. At intervals of six, twelve, twenty-four, thirty-six, forty-eight, and seventy-two hours, samples were evaluated for sperm motility and vigor. Fresh ejaculates had an average volume of 6.2 mL, white color, watery to milky appearance, "sui generis" odor, 89.5% sperm motility, 4.3 sperm vigor, average concentration of 418 x106 spermatozoa/mL and 7.3%pathological changes. After the beginning of cooling at 5 °C, the values of motility and vigor decreased over time, with the lowest values found after 48 and 72 hours. The in natura coconut water extender proved to be efficient for cooling canine semen at5 ºC, keeping it for a period of up to 36 hours after harvest, as recommended by the Brazilian College of Animal Reproduction.(AU)

Artificial insemination in bitches contributes to the genetic La inseminación artificial en perras contribuye a la mejora genética de la especie, previene algunas enfermedades de transmisión sexual a través de la cópula y permite la reproducción de animales que no podrían copular de forma natural, ya sea por razones anatómicas, geográficas o de comportamiento. Sin embargo, no siempre es posible utilizar semen fresco, por lo que se requiere un diluyente para enfriarlo y mantenerlo viable durante un cierto período. Por tanto, el objetivo de este trabajo fue analizar semen canino diluido en agua de coco y refrigerado a 5 ºC en diferentes tiempos. Se utilizaron cinco sabuesos brasileños, realizándose tres colectas de semen de cada animal, con intervalos de siete días. Los eyaculados se mantuvieron a una temperatura de 37 ºC y se realizaron análisis macroscópicos (volumen, color, apariencia y olor) y microscópicos (motilidad, vigor, concentración y morfología espermática). Luego, los eyaculados se diluyeron en agua de coco natural a una concentración de 200 millones de espermatozoides/mL y se mantuvieron a una temperatura de 5 °C hasta por 72 horas. A intervalos de seis, doce, veinticuatro, treinta y seis, cuarenta y ocho y setenta y dos horas, se evaluó la motilidad y el vigor de los espermatozoides en las muestras. Los eyaculados frescos tuvieron un volumen promedio de 6,2 mL, color blanco, apariencia acuosa a lechosa, olor "sui generis", motilidad espermática de 89,5%, vigor espermático de 4,3, concentración promedio de 418 x106 espermatozoides/mL y cambios patológicos de 7,3%. Después del inicio del enfriamiento a 5 °C, los valores de motilidad y vigor disminuyeron con el tiempo, encontrándose los valores más bajos a las 48 y 72 horas. El diluyente de agua de coco in natura demostró ser eficaz para enfriar el semen canino a5 ºC, manteniéndolo por un período de hasta 36 horas después de la cosecha, según lo recomendado por el Colegio Brasileño de Reproducción Animal.(AU)

Estratégias farmacológicas para a manipulação do ciclo estral de fêmeas bovinas de raças de corte taurinas / Pharmacological approaches to manipulate bovine estrous cycle in taurine beef breeds

Este texto discute as estratégias farmacológicas para a manipulação do ciclo estral de fêmeas taurinas de corte, com foco na inseminação artificial em tempo fixo (IATF). Os zebuínos, rebanho predominante no Brasil, apresentam características de ciclo estral diferentes das raças taurinas, o que justifica a busca por estratégias hormonais adaptadas para o controle do ciclo estral nas subespécies. O estradiol combinado com a progesterona (P4) e prostaglandina F2 alfa (PGF) é o esquema hormonal mais comumente utilizado para a manipulação do ciclo estral em protocolos de IATF. Porém, o uso de GnRH combinado ou em substituição aos ésteres de estradiol vem sendo considerado. Coletivamente, os dados do nosso grupo reforçam a necessidade de customizar as abordagens para o controle do ciclo estral de acordo com a composição genética das fêmeas bovinas.(AU)

This text discusses pharmacological strategies to manipulate the estrous cycle of taurine and synthetic females, with a focus on timed artificial insemination (TAI). Zebu cattle, the predominant herd in Brazil, have different estrous cycle characteristics than taurine breeds, requiring different synchronization hormonal strategies for each subspecies. Estradiol combined with progesterone (P4) and prostaglandin F2 alpha (PGF) is the most used hormonal scheme for estrous cycle manipulation in TAI protocols. But the use of GnRH instead of estradiol esters is being considered. Collectively, our group's data reinforce the need to customize approaches to estrous cycle control according to the genetic composition of bovine females.(AU)

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics / Diversidade bacteriana em solos de prados andinos elevados perturbados por culturas de Lepidium meyenii avaliadas por metagenômica

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics / Diversidade bacteriana em solos de prados andinos elevados perturbados por culturas de Lepidium meyenii avaliadas por metagenômica

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.(AU)

A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.(AU)

Novel missense variant L46Q of fatty acid synthase gene and fatty acids content in Awassi sheep

This study was conducted to investigate the association between the polymorphism of the FASN gene with fatty acid content in Awassi sheep. A total of 100 male Awassi sheep between the ages of one and two and a half years old were used in this study. Phenotypic measurement was recorded at slaughter, and from each animal, the longissimus dorsi (LD) muscle samples were taken to analyze the fatty acid profile. Genotyping, sequencing reactions, and in silico tools were performed to confirm the variants in amplified fragments. The result of genotyping revealed two genotypes (AA and AB) of the ovine FASN gene (exon 3). Novel SNP (L46Q) was discovered only within the FASN gene (AB genotype). All utilized in silico tools revealed remarkably deleterious effects for the L46Q on the mutant protein structure, function, and stability. Association analysis revealed that the AB genotype has significantly (p < 0.05) higher levels of animal length and monounsaturated fatty acids (MUFA) with lower amounts of saturated fatty acids (SFA) content than the AA genotype. In conclusion, novel SNP (L46Q) was discovered within the FASN gene (AB genotype), made the animals that has the AB genotype associated with good meat quality traits and this polymorphism may serve as markers for meat quality.(AU)

Depicting latent variables considering different pig genetics and nutritional plans in crossbred pigs

We aimed to reduce the dimensionality of quantitative traits in pigs applying factor analysis. Quantitative variables were collected, and the factor analysis extracted five factors with biological meaning related to performance, carcass quality, carcass yield, meat quality, and initial pH. These factors were posteriorly used as dependent variable to evaluate the effects of genetic groups (Piau, Duroc, and Pietrain crossbreds), nutritional plans (low, medium and high lysine levels) and sex. An interaction effect between genetic group and sex was observed in performance, in which Duroc crossbred showed the greatest scores. The Pietrain genetic group showed greater values of carcass quality compared with Duroc and Piau, while Piau crossbred pigs had greater values for meat quality compared with Pietrain and Duroc. A greater carcass yield was observed in Pietrain crossbred compared with Duroc pigs. Pigs fed under low lysine level had the lowest performance values. Carcass yield was affected by nutritional plans, in which the medium lysine level showed the greatest values. Meat quality was improved by the nutritional plan with high lysine level compared with the low lysine level. Initial pH showed increased means when using nutritional plans with low and medium lysine levels in diet composition. With regard to sex effects, a greater carcass quality was found for gilts compared with barrows. The reduction of the data dimensionality allowed the joint evaluation of genetic group, nutritional plan, and sex based on new latent variables that represented the original dataset under easier framework based on factors' biological interpretation.(AU)