Método prático e eficiente para estimar a área foliar de gramíneas forrageiras tropicais

The method here proposed, nominated of leaf area – Federal University of Tocantins (AFUFT) fill out these flaws and bases on three measures of the leaf (total length, leaf blade base width and leaf blade middle width), decomposing it in a triangle and a trapeze for calculate of LA. AFUFT (method II) was compared with three methods: method I – indirect, with use of apparel of luminous interception (SunScan®); method III – direct, segmented the leaf in parts of 10 cm, followed by measure of segments blade middle width; method IV – direct, used scanners and computer software (here considered as standard method). The four methodologies were set up in a randomized block design, being the blocks the 24 stonemasons (4.0 m x 1.0 m) of Urochloa brizantha cv. 'Marandu'. The AFUFT presented the largest correlation coefficients (r= 0.99; p<0.05) with the standard method. The method I overestimated LA and LAI and the method III underestimated these variables. For obtaining the leaf area of tropical grasses, the method here presented is an promising, practice and agile tool, in relation to the other studied methods.O método aqui proposto, denomidado de Área Foliar – Universidade Federal do To- cantins (AFUFT) baseia-se em três medidas da folha (comprimento total, largura na base do limbo e largura no meio do limbo), decompondo-a em um triângulo e um trapézio para o calculo da AF. O AFUFT (método II) foi comparado com três métodos: método I – indireto, com uso de aparelho de interceptação luminosa (SunScan®); método III – segmenta as folhas em partes de 10 cm, seguido de medida da largura destes segmentos; método IV – utiliza-se scanners e programa computacional (aqui considerado como método padrão). As quatro metodologias foram testadas em blocos casualisados, sendo os blocos as 24 parcelas (4,0 m x 1,0 m) de Urochloa brizantha cv. ‘Marandu’. O método AFUFT apresentou os maiores coeficientes de correlação (r= 0,99; p<0,05) com o método padrão. Já o método I superes- timou a AF e o índice de área foliar e o método III subestimou estas variáveis. Para estima- tivas de área foliar de gramínea forrageira, o método aqui apresentado é uma ferramenta promissora, prática e ágil, em relação aos demais métodos estudados

Profiling the immune epigenome across global cattle breeds

Background Understanding the variation between well and poorly adapted cattle breeds to local environments and pathogens is essential for breeding cattle with improved climate and disease-resistant phenotypes. Although considerable progress has been made towards identifying genetic differences between breeds, variation at the epigenetic and chromatin levels remains poorly characterized. Here, we generate, sequence and analyse over 150 libraries at base-pair resolution to explore the dynamics of DNA methylation and chromatin accessibility of the bovine immune system across three distinct cattle lineages. Results We find extensive epigenetic divergence between the taurine and indicine cattle breeds across immune cell types, which is linked to the levels of local DNA sequence divergence between the two cattle sub-species. The unique cell type profiles enable the deconvolution of complex cellular mixtures using digital cytometry approaches. Finally, we show distinct sub-categories of CpG islands based on their chromatin and methylation profiles that discriminate between classes of distal and gene proximal islands linked to discrete transcriptional states. Conclusions Our study provides a comprehensive resource of DNA methylation, chromatin accessibility and RNA expression profiles of three diverse cattle populations. The findings have important implications, from understanding how genetic editing across breeds, and consequently regulatory backgrounds, may have distinct impacts to designing effective cattle epigenome-wide association studies in non-European breeds