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Iron oxide-copper–gold (IOCG) deposit genesis is often genetically linked to magmatism due to temporal association between granite and mineralization and participation of magma-derived components. In the Carajás Mineral Province, NW Brazil, a set of ca. 2.6–2.5 Ga IOCG deposits has been interpreted to be genetically linked to contemporary granite, which are located along the Cinzento Shear Zone, in the northern part of the province. Despite the apparent temporal correlation, the understanding of ca. 2.5 Ga ages as magmatic may be misleading, since ca. 2.6–2.5 Ga reset ages have been previously reported for deformed and hydrothermally altered granites crystallized at ca. 2.74 Ga. We studied the morphology, texture, and composition of 2.74–2.73 Ga, 2.68 Ga, 2.64–2.62 Ga, and 2.59–2.55 Ga zircons from variably deformed and metasomatized granites located along the Cinzento Shear Zone. Our study reveals re-equilibrated magmatic, deformed, and newly grown zircon domains with compositional changes (Ta, U, Y, and LREE enrichment relative to chondrite) that inconsistently follow textural patterns. The overprint arises from diffusion–reaction, coupled-dissolution-reprecipitation processes, and alteration of metamict zircons, likely aided by alkaline (Na–K-rich) and F-Cl-rich hydrothermal fluids that circulated regionally in the Carajás Province. Such processes account for disturbances and resetting of the U-Th-Pb isotopic system in zircon; therefore, the geochronological record in granites from our study can be associated with the first (ca. 2.72–2.68 Ga) and the second (ca. 2.6–2.5 Ga) IOCG-forming hydrothermal events rather than to igneous crystallization. In this context, we rule out a temporal link between granitic magmatism and the IOCG deposits at Carajás. [ABSTRACT FROM AUTHOR]

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In Brazil, commonly males of dairy herd are destined to beef production. However, little is known about the mineral requirements for dairy males. Therefore, the objective of this experiment was to evaluate the calcium (Ca) requirements of Holstein×Zebu steers by determining Ca body tissue concentrations, true absorption and retention coefficients, as well as the requirements for maintenance and weight gain of steers fed diets containing or not containing dicalcium phosphate. Twenty-eight Holstein×Zebu steers with an average initial body weight of 377.5±49.4 kg were utilized. The experiment was conducted as a completely randomized design with a 2×2 factorial arrangement of treatments. Factors included 1) two concentrate levels (30% or 60%); and 2) two levels of dicalcium phosphate (DP), 0 or the amount necessary to attend the estimated dietary requirements. Absorption and retention coefficients, maintenance and gain requirements were estimated. The feedstuffs, refusals, feces, urine, blood and bone were sampled for Ca and phosphorus (P) analysis. Phosphorus intake was improved by the addition of concentrate and presence of DP. There were no variations in the daily fecal and urinary phosphorus excretion as a function of DP. The serum level of inorganic phosphorus was lower in non-supplemented animals, although it was within adequate concentrations for all treatments. Dry matter and organic matter intake, organic matter digestibility, performance, and efficiency were not affected by treatment. Absorption and retention coefficients, and the net requirements for maintenance are similar across treatments. Therefore, the lack of inorganic supplementary Ca and P in diets of feedlot finishing cattle does not change the concentrations of these minerals in bone. The dietary requirements of calcium and phosphorus obtained for cattle were lower than those described by the nutritional requirement systems from Brazil, USA, and UK. [ABSTRACT FROM AUTHOR]

Background & Aims: We aimed to estimate the prevalence of the inadequate intake and status of magnesium, zinc, and vitamins A, C, E, and D and identify factors associated with micronutrient deficiency in serum/plasma among residents of São Paulo, Brazil., Methods: Data from 824 individuals aged ≥14 years were obtained from the 2015 ISA-Nutrition, a population-based, cross-sectional survey. Dietary and supplement intakes were assessed using two 24-h dietary recalls, and the micronutrient inadequacies were estimated using the National Cancer Institute method. Micronutrient status was measured in serum or plasma, and deficiency was established according to the lower limit of the reference values. Receiver operating characteristic curve analysis was used to identify the effect of intake on the micronutrient status in serum/plasma. Logistic regression analysis was applied to assess the association between micronutrient status and individual characteristics., Results: More than 80% of the population had an inadequate dietary intake of magnesium, vitamin E, and vitamin D. Males had a high prevalence of inadequate dietary intake of vitamin A and zinc. A high-to-moderate prevalence of inadequate vitamin C intake was observed. Vitamin D was the only nutrient with a deficient status comparable to its dietary inadequacy. The other nutrients demonstrated a lower deficiency prevalence compared to dietary inadequacy, and vitamin A demonstrated the lowest prevalence of deficiency in plasma. Generally, dietary intake showed a non-notable association with micronutrient deficiency in serum/plasma. Individuals with fasting glucose concentrations ≥100 mg/dL and those using diuretic drugs had a higher risk of serum magnesium deficiency. Those using lipid-lowering drugs and those with high plasma adiponectin concentrations had a higher risk of serum zinc deficiency. Individuals who smoked and those with hypertension showed a higher risk of plasma vitamin C deficiency. Individuals with average leptin concentrations had a higher risk of plasma vitamin E deficiency. Finally, those with sufficient leisure-time physical activity had a lower risk of serum vitamin D deficiency., Conclusions: Residents of the urban areas of São Paulo demonstrated substantially inadequate intakes of most of the assessed micronutrients; however, micronutrient deficiency in serum/plasma was not associated with dietary inadequacy, and it usually demonstrated a lower prevalence than dietary indicators. Thus, using micronutrient intake to determine the serum/plasma profile should be done with caution. The status of the micronutrients varied according to individual characteristics, indicating the interplay of complex mechanisms underlying micronutrient balance., Competing Interests: Conflict of interest All authors declare no conflicts of interest that could inappropriately influence this article., (Copyright © 2022 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.)

The purpose of this work was to determine the concentration of copper in samples of farmed Nile tilapia (Oreochromis niloticus L.) fillets purchased in the city of Botucatu (São Paulo, Brazil) and in fillet and liver samples of Tilapia fed diets supplemented with different concentrations of Cu from the Laboratory of Aquatic Organism Nutrition/FMVZ-UNESP (Botucatu, Brazil). The fillet samples were prepared by lyophilisation and cryogenic grinding into particles smaller than 60 µm, and copper was extracted ultrasonically using 0.10 mol l−1 HCl as extraction solution. Copper determination was performed by graphite furnace atomic absorption spectrometry (GFAAS) with optimised temperatures of drying, pyrolysis, atomisation and cleaning. Palladium nitrate was injected into the samples as a chemical modifier and tungsten as a permanent modifier. Copper concentrations of 0.70–1.60 mg kg−1 were found, which are in line with Brazilian regulations. The accuracy and precision of the copper concentrations determined in this study were evaluated using certified standard Lake Michigan fish tissue (NIST SRM 1947). [ABSTRACT FROM PUBLISHER]

Copyright of Brazilian Journal of Food & Nutrition / Alimentos e Nutrição is the property of Faculdade de Ciencias Farmaceuticas, UNESP and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• First study gauging heavy metals and antagonist levels in Brazilian dairy products. • Principal heavy metals observed in dairy products of São Luís were Hg, Pb, and Ni. • Calcium (Ca), lead's antagonist, was highly concentrated in dairy products. To assess the levels of heavy metals and their antagonists in dairy products available in the markets of São Luís, northeastern Brazil. Chemical analysis of the heavy metals copper(Cu), lead(Pb), mercury(Hg), and nickel(Ni) and their antagonists iron(Fe), zinc(Zn), calcium(Ca), selenium(Se), and cobalt(Co) contained in dairy products using inductively coupled plasma optical emission spectrometry (ICP-OES). The main heavy metal observed in dairy products were Hg; Pb; Se and Ni. A significant negative correlation was observed between the concentrations of Cu and Fe (rho = −0.634, p = 0.001), Cu and Zn (rho = −0.794, p = 0.000) in whole milk. A non-significant positive correlation was observed between Pb and Ca (rho = 0.387, p = 0.056), and Hg and Se (rho = 0.055, p = 0.795). Dairy product brands available in the markets of São Luís could be considered a source of heavy metal contamination (Hg, Pb, Se, Cu, Ni) with weak correlations with their antagonists. [ABSTRACT FROM AUTHOR]

International committees that have published nutrient requirements for dairy cattle have used data from mineral studies conducted in the 1920s to 1970s, and no study has reported data from animals less than 100 kg; therefore, there is a need to update mineral requirements for preweaned dairy calves. Thus, a meta-analysis was performed to estimate the mineral requirements of Ca, P, K, Mg, and Na for Holstein and Holstein × Gyr crossbred preweaned dairy calves using data from 5 studies developed at the Universidade Federal de Viçosa (Viçosa, MG, Brazil). A total of 210 calves were separated into 2 breeds: purebred Holstein calves (animals with a Holstein pedigree higher than 87.5%) and Holstein × Gyr crossbred calves (animals with a Holstein pedigree lower than 87.5%). The comparative slaughter technique was used to estimate animal body composition and empty body weight (EBW). Mineral requirements for maintenance were estimated by the regression between retained mineral and mineral intake, whereas mineral requirements for gain were obtained from the first derivative of the mineral content in the animal's body. In addition, breed effect was tested on the intercept and slope of the models. The effect of breed was not observed for all analyzed variables. Thus, net requirements for maintenance were 12.73, 11.81, 20.28, 3.50, and 6.37 mg/kg of EBW per day for Ca, P, K, Mg, and Na, respectively. Retention coefficients were 73.18, 65.20, 13.16, 29.55, and 24.28% for Ca, P, K, Mg, and Na, respectively. The following equations were determined to estimate net requirements for gain (NRG, g/d): NRG for Ca = 14.402 × EBW -0.139 × empty body gain (EBG); NRG for P = 5.849 × EBW -0.027 × EBG; NRG for K = 1.140 × EBW -0.048 × EBG; NRG for Mg = 0.603 × EBW -0.036 × EBG; and NRG for Na = 1.508 × EBW -0.045 × EBG. Due to the high variation between the data found in this study and in the available literature, we suggest that further studies should be conducted to evaluate the estimates of this study., (Copyright © 2019 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Moringa oleifera Lam. is a leguminous plant, originally from Asia, which is cultivated in Brazil because of its low production cost. Although some people have used this plant as food, there is little information about its chemical and nutritional characteristics. The objective of this study was to characterise the leaves of M. oleifera in terms of their chemical composition, protein fractions obtained by solubility in different systems and also to assess their nutritional quality and presence of bioactive substances. The whole leaf flour contained 28.7% crude protein, 7.1% fat, 10.9% ashes, 44.4% carbohydrate and 3.0mg 100g(-1) calcium and 103.1mg 100g(-1) iron. The protein profile revealed levels of 3.1% albumin, 0.3% globulins, 2.2% prolamin, 3.5% glutelin and 70.1% insoluble proteins. The hydrolysis of the protein from leaf flour employing sodium dodecyl sulfate (SDS) and 2-mercaptoethanol (ME) resulted in 39.5% and 29.5%, respectively. The total protein showed low in vitro digestibility (31.8%). The antinutritional substances tested were tannins (20.7 mg g(-1)), trypsin inhibitor (1.45TIU mg g(-1)), nitrate (17 mg g(-1)) and oxalic acid (10.5 mg g(-1)), besides the absence of cyanogenic compounds. β-Carotene and lutein stood out as major carotenoids, with concentrations of 161.0 and 47.0 μg g(-1) leaf, respectively. Although M. oleifera leaves contain considerable amount of crude protein, this is mostly insoluble and has low in vitro digestibility, even after heat treatment and chemical attack. In vivo studies are needed to better assess the use of this leaf as a protein source in human feed., (Copyright © 2013 Elsevier Ltd. All rights reserved.)