São Carlos, Brazil
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Amaral C.D.B.,Federal University of São Carlos | Nobrega J.A.,Federal University of São Carlos | Nogueira A.R.A.,Embrapa Southeast Livestock
Talanta | Year: 2013

Arsenic is an element widely present in nature. Additionally, it may be found as different species in several matrices and therefore it is one of the target elements in chemical speciation. Although the number of studies in terrestrial plants is low, compared to matrices such as fish or urine, this number is raising due to the fact that this type of matrix are closely related to the human food chain. In speciation analysis, sample preparation is a critical step and several extraction procedures present drawbacks. In this review, papers dealing with extraction procedures, analytical methods, and studies of species conservation in plants cultivated in terrestrial environment are critically discussed. Analytical procedures based on extractions using water or diluted acid solutions associated with HPLC-ICP-MS are good alternatives, owing to their versatility and sensitivity, even though less expensive strategies are shown as feasible choices. © 2013 Elsevier B.V.

Amaral C.D.B.,Federal University of São Carlos | Nobrega J.A.,Federal University of São Carlos | Nogueira A.R.A.,Embrapa Southeast Livestock
Microchemical Journal | Year: 2014

In studies of speciation, the conservation of species in their original forms is a very challenging issue, and the reliability of the results deeply depends on it. Preliminary steps of sample preparation and storage temperature may influence the conservation of species and extraction efficiency. Plant sample (Brachiaria brizantha Stapf. cv. Marandu) grown in As-containing soil was harvested and divided into four portions. The first portion was frozen-dried, milled with liquid N2 and stored at room temperature; the second portion was lyophilized and stored at 4°C; and the remaining portions were kept at two storage temperatures (-18 and -80°C) without any prior procedure. Aliquots of samples stored under different conditions were extracted every 2months for a 12-month period. The total content of As was 2.30±0.27mg kg-1 of dried and ground sample and As species were determined by HPLC-ICP-MS. The extraction was more efficient in sample aliquots that were lyophilized and ground (87-90%) than those only stored under different temperatures (53-66%). Furthermore, only for lyophilized and ground samples dimethylarsenic acid (DMA) was extracted. Concerning the storage time under the two tested temperatures, no significant differences on species were found and they remained stable. Standard deviations for replicates of samples that were not frozen-dried and ground were higher, and this behavior can be explained by sample heterogeneity. For the As species here studied it can be concluded that lyophilization and cryogenic grinding strategies were the most suitable sample pretreatments for As speciation in plant tissue. © 2014 Elsevier B.V.

Leme A.B.P.,Federal University of São Carlos | Bianchi S.R.,Embrapa Southeast Livestock | Carneiro R.L.,Federal University of São Carlos | Nogueira A.R.A.,Embrapa Southeast Livestock
Food Analytical Methods | Year: 2014

In this paper, analytical procedures are proposed for determination of inorganic constituents in honey samples from different regions of Brazil. Inductively coupled plasma with mass spectrometry detection (ICP-MS) was used to determine the analytes, using two different sample preparation methods: acid mineralization in block digester and microwave-assisted acid digestion. The methods were optimized in order to minimize the final acidity and the residual carbon content after the sample preparation. It was observed that mineralization using microwave radiation with 2 mol L-1 HNO3 was the most suitable method for determination of minerals and trace elements by ICP-MS. Besides, Se, Mg, Ca, Al, P, Mn, Fe, Cu, Zn, Ba, and Pb were determined in 60 honey samples by ICP-MS. The appropriate instrumental conditions were also evaluated for this determination, as the need of the use of collision-reaction interface and internal standards. The accuracies were evaluated using two certified reference materials, and the recoveries ranged from 82 to 115 %. The results showed no evidence of contamination in the honey samples analyzed. © 2013 Springer Science+Business Media New York.

Amaral C.D.B.,Federal University of São Carlos | Dionisio A.G.G.,Federal University of São Carlos | Santos M.C.,São Paulo State University | Donati G.L.,Federal University of São Carlos | And 2 more authors.
Journal of Analytical Atomic Spectrometry | Year: 2013

Different conditions of extraction using water, a methanol-water mixture and nitric acid solutions were evaluated for speciation of As(iii), As(v), DMA and MMA in plant samples that previously received As(v) after being sown and emergence was investigated. Microwave-assisted extraction (MAE) using diluted nitric acid solutions was also performed for arsenic extraction from chicken feed samples. The separation and determination of arsenic species were performed using HPLC-ICP-MS. The interference standard method (IFS) using 83Kr+ as the IFS probe was employed to minimize spectral interferences caused by polyatomic species, such as 40Ar 35Cl+. The extraction procedures tested presented adequate extraction efficiencies (90%), and the four arsenic species evaluated were found in plant samples. Extractions with diluted nitric acid solution at 90 °C were the most efficient strategy, with quantitative recoveries for all four As species in plant tissues. On the other hand, the methanol-water mixture was the solvent with the lowest extraction efficiency (50-60%). For chicken feed samples, MAE at 100 °C for 30 min resulted in an extraction efficiency of 97% and only As(v) was found, without any species interconversion. The IFS method contributed to improving precision and limits of detection and quantification for all tested extraction procedures. Significant improvements on accuracy were obtained by applying the IFS method and recoveries between 77 and 94%, and 82 and 93% were obtained for plant extracts and chicken feed samples, respectively. This journal is © 2013 The Royal Society of Chemistry.

PubMed | São Paulo State Technological College, São Paulo State University, Embrapa Agricultural Informatics and Embrapa Southeast Livestock
Type: | Journal: Journal of animal science and biotechnology | Year: 2016

Recent technological advances in genomics have allowed the genotyping of cattle through single nucleotide polymorphism (SNP) panels. High-density SNP panels possess greater genome coverage and are useful for the identification of conserved regions of the genome due to selection, known as selection signatures (SS). The SS are detectable by different methods, such as the extended haplotype homozygosity (EHH); and the integrated haplotype score (iHS), which is derived from the EHH. The aim of this study was to identify SS regions in Canchim cattle (composite breed), genotyped with high-density SNP panel.A total of 687,655 SNP markers and 396 samples remained for SS analysis after the genotype quality control. The iHS statistic for each marker was transformed into piHS for better interpretation of the results. Chromosomes BTA5 and BTA14 showed piHS>5, with 39 and nine statistically significant SNPs (P<0.00001), respectively. For the candidate selection regions, iHS values were computed across the genome and averaged within non-overlapping windows of 500 Kb. We have identified genes that play an important role in metabolism, melanin biosynthesis (pigmentation), and embryonic and bone development.The observation of SS indicates that the selection processes performed in Canchim, as well as in the founder breeds (i.e. Charolais), are maintaining specific genomic regions, particularly on BTA5 and BTA14. These selection signatures regions could be associated with Canchim characterization.

PubMed | Embrapa Agricultural Informatics, Embrapa Southeast Livestock, State University of Mato Grosso do Sul, Embrapa Beef Cattle and 4 more.
Type: | Journal: BMC genomics | Year: 2016

Nelore is the major beef cattle breed in Brazil with more than 130 million heads. Genome-wide association studies (GWAS) are often used to associate markers and genomic regions to growth and meat quality traits that can be used to assist selection programs. An alternative methodology to traditional GWAS that involves the construction of gene network interactions, derived from results of several GWAS is the AWM (Association Weight Matrices)/PCIT (Partial Correlation and Information Theory). With the aim of evaluating the genetic architecture of Brazilian Nelore cattle, we used high-density SNP genotyping data (~770,000 SNP) from 780 Nelore animals comprising 34 half-sibling families derived from highly disseminated and unrelated sires from across Brazil. The AWM/PCIT methodology was employed to evaluate the genes that participate in a series of eight phenotypes related to growth and meat quality obtained from this Nelore sample.Our results indicate a lack of structuring between the individuals studied since principal component analyses were not able to differentiate families by its sires or by its ancestral lineages. The application of the AWM/PCIT methodology revealed a trio of transcription factors (comprising VDR, LHX9 and ZEB1) which in combination connected 66 genes through 359 edges and whose biological functions were inspected, some revealing to participate in biological growth processes in literature searches.The diversity of the Nelore sample studied is not high enough to differentiate among families neither by sires nor by using the available ancestral lineage information. The gene networks constructed from the AWM/PCIT methodology were a useful alternative in characterizing genes and gene networks that were allegedly influential in growth and meat quality traits in Nelore cattle.

PubMed | Embrapa Beef Cattle, Embrapa Southeast Livestock and University of Sao Paulo
Type: | Journal: Meat science | Year: 2016

Five hundred and seventy-five Nellore steers were evaluated for residual feed intake and residual feed intake and gain and their relationships between carcass, non-carcass and meat quality traits. RFI was measured by the difference between observed and predicted dry matter intake and RIG was obtained by the sum of -1*RFI and residual gain. Efficient and inefficient animals were classified adopting 0.5 standard deviations from RFI and RIG mean. A mixed model was used including RFI or RIG and contemporary group as fixed effects, initial age as covariate and sire and experimental period as random effects, testing the significance of the regression slope for each evaluated trait. RIG was positively related to longissimus muscle area. Efficient-RFI animals had lower liver and internal fat proportions compared to inefficient-RFI animals. Efficient-RFI and efficient-RIG animals had 11.8% and 11.2% lower extracted intramuscular fat, compared to inefficient-RFI and inefficient-RIG animals, respectively. Efficient-RFI animals had tougher meat compared to inefficient-RFI animals.

Castelani L.,Institute of Animal Science | Silva Santos A.F.,Institute of Animal Science | Miranda M.S.,Institute of Animal Science | Zafalon L.F.,Embrapa Southeast Livestock | And 2 more authors.
International Journal of Molecular Sciences | Year: 2013

Staphylococcus aureus is among the main etiologic agents of bovine mastitis. A total of 83 isolates of S. aureus from mammary glands of primiparous heifers were collected in the prepartum, calving and during lactation. For lactating cows, a total of 27 isolates of S. aureus from mammary glands were collected during lactation. The samples were taken in two dairy farms located in Sao Paulo State, Brazil. The highest frequency of S. aureus isolation in heifers was at the end of lactation. Strains were typified through Pulsed-field gel electrophoresis (PFGE) and grouped according to patterns of restriction enzyme SmaI. PFGE generated seven clonal profiles that were grouped into three different lineages, with the LA lineage being predominant and identified in heifers, as well as in the cows from the two regions studied. It was concluded that the cows showed a significant source of dispersion of S. aureus. At the first lactation the heifers were infected by the same clonal profiles of S. aureus which were isolated from multiparous lactating cows. The heifers were infected during milking over the months of lactation. © 2013 by the authors; licensee MDPI, Basel, Switzerland.

PubMed | University of Missouri, Embrapa Southeast Livestock and Texas A&M University
Type: Journal Article | Journal: PloS one | Year: 2016

Unlike the genomes of many mammals that have a single NK-lysin gene, the cattle genome contains a family of four genes, one of which is expressed preferentially in the lung. In this study, we compared the expression of the four bovine NK-lysin genes in healthy animals to animals challenged with pathogens known to be associated with bovine respiratory disease (BRD) using transcriptome sequencing (RNA-seq). The expression of several NK-lysins, especially NK2C, was elevated in challenged relative to control animals. The effects of synthetic peptides corresponding to functional region helices 2 and 3 of each gene product were tested on both model membranes and bio-membranes. Circular dichroism spectroscopy indicated that these peptides adopted a more helical secondary structure upon binding to an anionic model membrane and liposome leakage assays suggested that these peptides disrupt membranes. Bacterial killing assays further confirmed the antimicrobial effects of these peptides on BRD-associated bacteria, including both Pasteurella multocida and Mannhemia haemolytica and an ultrastructural examination of NK-lysin-treated P. multocida cells by transmission electron microscopy revealed the lysis of target membranes. These studies demonstrate that the expanded bovine NK-lysin gene family is potentially important in host defense against pathogens involved in bovine respiratory disease.

Palhares J.C.P.,Embrapa Southeast Livestock | Pezzopane J.R.M.,Embrapa Southeast Livestock
Journal of Cleaner Production | Year: 2015

Abstract The amount of water that is used in animal agriculture influences society's view of its environmental sustainability. Estimates of how much water is consumed to produce one kg of milk remain scarce. Such information needs to be given to society and water resource managers. The aim of this study were to assess the water footprint of both a conventional and an organic dairy production system and identified the components and processes that have the greatest water use in terms of green, blue, gray water, and virtual water. Additionally, it analyzed the impact of element on gray water footprint, and utilized indicators to evaluate the water scarcity. These were done following a water footprint method compliant with Water Footprint Network. Green water footprint was the most significant contributor to the total footprint values for both systems. This situation can be understood as an opportunity to improve the agriculture water use efficiency and promote the integration between agriculture and livestock. Virtual water represents from 39% to 57% of footprint value for the conventional and from 32% to 59% for the organic. The consumption of water for irrigation accounted for the greatest percentage of blue water, 95% for conventional and 96% for organic. The element used to calculate gray water footprint has a significant impact on its values. Footprints calculated having phosphorus as element were 1.5 and 1.9 times higher for conventional and organic, respectively. Both conventional and organic farms showed an equal green water scarcity index (1.1) and despite the two farms are located in places with high rainfall, they suffered green water scarcity The blue water scarcity index was 0.11 for conventional and 0.13 for organic. Study concluded that a product with a lower water footprint could be more damaging to the environment than one with a higher water footprint depending on water availability. The water footprint approach evidenced that nutritional management is crucial to improve water use. Results cannot support the consequences in changing the conventional or the organic production system regarding the use of water. The more efficient water use depend on productions factors and water availabilities that are specific to each system. © 2015 Elsevier Ltd. All rights reserved.

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