Zn Source Research Articles

Zinc solubilization and organic acid production by the entomopathogenic fungus, Metarhizium pingshaense sheds light on its key ecological role in the environment

We report for the first-time higher zinc (Zn) solubilization efficiency and plant growth promotion by an entomopathogenic fungus (EPF), Metarhizium pingshaense IISR-EPF-14, which was earlier isolated from Conogethes punctiferalis, a pest of global importance. The Zn solubilizing efficiency of the fungus varied depending on the type of insoluble source of Zn used, which was observed to be 1.6 times higher in Zn3(PO4)2–amended media compared to ZnO media. In liquid media, there was a 6.2-fold increase in available Zn in ZnO–amended media, whereas a 20.2-fold increase in available Zn was recorded in Zn3(PO4)2 medium. We ascribe the production of various organic acids such as gluconic, keto-gluconic, oxalic, tartaric, malonic, succinic and formic acids, which in general, interact with insoluble Zn sources and make them soluble by forming metal cations and displacing anions as the major mechanism for Zn solubilization by M. pingshaense. However, the type and amount of organic acid produced in the media varied depending on the source of Zn used and the incubation period. Application of the fungus alone and in combination with insoluble Zn sources enhanced various plant growth parameters in rice and cardamom plants. Moreover, the uptake of Zn in rice plants was enhanced up to ~2.5-fold by fungal application. The fungus also exhibited various other plant growth-promoting traits, such as production of Indole-3-acetic acid, ammonia, siderophores, solubilization of mineral phosphate, and production of hydrolytic enzymes such as α-amylase, protease, and pectinase. Hence, apart from its use as a biological control agent, M. pingshaense has the potential to be used as a bio-fortifier to enhance the solubilization and uptake of Zn from nutrient poor soils under field conditions. Our findings shed light on the broader ecological role played by this fungus and widen its scope for utilization in sustainable agriculture.

Enzymatic alterations of soil and plant system on applied Zn sources, organics and microbial inoculants in zinc deficient calcareous and non-calcareous soils

The study aimed to investigate the impact of zinc (Zn) nutrition on enzymatic activity in soil and plant systems of zinc-deficient soils. Additionally, it aimed to understand the impact of solubilizer (such as Zinc Solubilizing Bacteria) and mobilizer (like AM Fungi) on enzyme activity and zinc nutrition in plants across calcareous and non-calcareous soil environments. A pot experiment was carried out with two different soils with three Zn sources (ZnSO4, ZnO and Zn-EDTA), organic manure (FYM) and microbial inoculants - Zinc Solubilizing Bacteria (ZSB) and Arbuscular Mycorrhizal Fungi (AM F). The DTPA-Zn and plant Zn content increased with applied sources of Zn. The microbial inoculants and FYM enhanced the use efficiency of all sources of Zn compared to unapplied treatments. Regarding soil enzyme activity, FYM and AM fungi played a major role which in turn altered the dehydrogenase (SDHA) and alkaline phosphatase (AlP) activities in both soils. The Zn sources and ZSB addition enhanced the plant enzyme activity. Calcareous soil recorded higher CA, SOD and alkaline phosphatase activities compared to non-calcareous soil the latter registered higher dehydrogenase activity and fruit Zn content.

Examining the Impact of Long-Term Industrialization on the Trace Metal Contaminants Distribution in Seawater of the Pula Bay, Croatia

In this study, we examined for the first time the spatio-temporal distribution of trace metal (TM) contaminants (Zn, Cd, Pb, Cu, Ni and Co) in the seawater column of Pula Bay. The bay has been known for decades as one of the most industrialized regions on the Croatian side of the Adriatic. Water samples were collected at 20 sites (at two depths) in four different seasons. The main physico-chemical parameters and DOC were measured along the TMs. The spatial distribution clearly showed that areas with industrial and nautical activities are sources of Zn, Pb and Cu, while no increase was observed for Cd, Ni and Co. Compared to the reference area outside the bay, the increase in dissolved concentrations ranged from a factor of 1.1 for Ni and Co to 8.5 for Pb. A clear difference in TM concentrations was observed between seasons, with concentrations being higher in warmer periods than in colder periods. The potential bioavailability/toxicity of TMs was examined using a passive sampling technique: diffusive gradients in thin films (DGT). In addition, a single-factor pollution index based on the available EQSs was used for both the dissolved TMs and DGT to assess the potential risk to the environment.

Seasonal and multi-decadal zinc isotope variations in blue mussels from two sites with contrasting zinc contamination levels

Zinc (Zn) isotope compositions in soft mussel tissues help identify internal biological processes and track coastal Zn sources in coastal environments, thus aiding in managing marine metal pollution. This study investigated the seasonal and multi-decadal Zn isotope compositions of blue mussels (genus Mytilus) from two French coastal sites with contrasting Zn environmental contamination. Concurrently, we characterized the isotope ratios of sediments and plankton samples at each site to understand the associations between organisms and abiotic compartments. Our primary objective was to determine whether these isotope compositions trace long-term anthropogenic emission patterns or if they reflect short-term biological processes. The multi-decadal isotope profiles of mussels in the Loire Estuary and Toulon Bay showed no isotope variations, implying the enduring stability of the relative contributions of natural and anthropogenic Zn sources over time. At seasonal scales, Zn isotope ratios were also constant; hence, isotope effects related to spawning and body growth were not discernible. The multi-compartmental analysis between the sites revealed that Toulon Bay exhibits a remarkably lower Zn isotope ratio across all studied matrices, suggesting the upward transfer of anthropogenic Zn in the food web. In contrast, the Zn isotope variability observed for sediments and organisms from the Loire Estuary fell within the natural baseline of this element. In both sites, adsorptive geogenic material carrying significant amounts of Zn masks the biological isotope signature of plankton, making it difficult to determine whether the Zn isotope ratio in mussels solely reflects the planktonic diet or if it is further modified by biological homeostasis. In summary, Zn isotope ratios in mussels offer promising avenues for delineating source-specific isotope signatures, contingent upon a comprehensive understanding of the isotope fractionation processes associated with the trophic transfer of this element through the plankton.

A biocompatible NPK+Fe+Zn slow release fertilizer: synthesis and its evaluation in tomato plant growth improvement

Slow-release fertilizers (SRFs) play an essential and necessary role in sustainable agriculture. Using slow-release and environment friendly fertilizers can increase the growth of plants and reduce the loss of nutrients. Considering the deficiency of iron (Fe) and zinc (Zn) in calcareous soils, a slow-release fertilizer was prepared based on the polymeric nanocomposite, which contains NPK, Fe, and Zn. Its potential was evaluated on tomato plant growth by conducting an experiment in a factorial completely randomized design with three replications. Two levels of salinity (2 and 5 ds m−1, two types of soil texture) clay loam and sandy loam) and five levels of fertilizers were examined in the experiment. To this, the graphene oxide-chitosan coated-humic acid@Fe3O4 nanoparticles (Fe3O4@HA@GO-Cs), and the graphene oxide-chitosan coated-ammonium zinc phosphate (AZP@GO-Cs) were used as Fe and Zn sources, respectively. Then, the optimal Fe and Zn fertilizers in the presence of urea, phosphorus, and potassium slow- release fertilizers (SRF) were investigated under greenhouse conditions. The results indicated that the best improvement in growth and nutrient uptake in plants was achieved by using the SRF. Notably, in the shoots of tomato plants, the nitrogen, phosphorus, potassium, Fe, and Zn concentration increased by 44, 66, 46, 75, and 74% compared to the control. The use of nanofertilizer can be an effective, biocompatible, and economical option to provide Fe and Zn demand in plants.

Bone characteristics, pre-caecal phytate degradation, mineral digestibility and tissue expression were marginally affected by zinc level and source in phytase-supplemented diets in 21-day-old broiler chickens

ABSTRACT 1. This study determined the effect of dietary Zn concentration and source in phytase-supplemented diets on bone mineralisation, gastrointestinal phytate breakdown, mRNA-level gene expression (in jejunum, liver and Pectoralis major muscle) and growth performance in broiler chickens. 2. Male Cobb 500 broilers were housed in floor pens (d 0-d 21) to test seven treatments with six replicate pens (12 birds per pen). Diets were arranged in a 2 × 3 + 1-factorial arrangement. The experimental factors were Zn source (Zn-oxide (ZnO) or Zn-glycinate (ZnGly) and Zn supplementation level (10, 30 or 50 mg/kg of diet). A maize-soybean meal-based diet without supplementation and formulated to contain 28 mg Zn/kg (analysed to be 35 mg Zn/kg), served as a control. 3. Zinc source and level did not influence (p > 0.05) bone ash concentration and quantity or mineral concentrations in bone ash. Tibia thickness was greater in the treatment ZnO10 than in the treatments ZnO30 and ZnGly50 (Zn level × Zn source: p = 0.036), but width and breaking strength were not affected. 4. Pre-caecal P digestibility and concentrations of phytate breakdown products in the ileum, except for InsP5, were not affected by Zn source or level. Only the expression of EIF4EBP1 (eukaryotic translation initiation factor 4E-binding protein 1) and FBXO32 (F-box only protein 32) in Pectoralis major muscle was affected by source, where expression was increased in ZnO compared to ZnGly diets (p < 0.05). 5. In conclusion, Zn level and source did not affect gastrointestinal phytate degradation and bone mineralisation in phytase-supplemented diets. The intrinsic Zn concentration appeared to be sufficient for maximum bone Zn deposition under the conditions of the present study but requires validation in longer-term trials.

Discrimination of metal contaminant sources in river sediments influenced by mining and smelting activities using stable Pb and Zn isotopes.

To determine the sources and pathways of lead (Pb) and zinc (Zn) in river sediments contaminated with metals from mining and smelting activities, metal concentrations and Pb and Zn isotope ratios were measured in river water and sediment, and potential metal contaminant samples (imported Zn concentrates, smelting wastes, soils around the smelter, mine ores, and riverside tailings). Zn and cadmium (Cd) concentrations in river water and sediment samples were 30- and 11-25-fold higher, respectively, near the smelter than upstream, while a 6-fold increase in sediment Pb concentrations was detected over the same region. Sediment samples near the smelter (207Pb/206Pb = 0.8638 and 208Pb/206Pb = 2.0960) were observed to have a different Pb isotopic composition from upstream of the smelter (207Pb/206Pb = 0.8322 and 208Pb/206Pb = 2.0502), with δ66Zn values increasing from -0.01 to 0.82‰. Analysis of Pb and Zn isotopes and concentrations revealed that dust-contaminated soils were a major Pb source, and baseline sediments were found to be contaminated by regional mining tailings. For Zn in sediments, the main Zn sources were groundwater-derived Zn (δ66Zn = 1.02 ± 0.43‰, n = 4), dust-contaminated soils (δ66Zn = -0.18 ± 0.08‰, n = 3), and tailings-contaminated sediments (δ66Zn = 0.01 ± 0.07‰, n = 10). Endmember mixing model results showed that dust-contaminated soils contributed 78% and 64% of sediment Pb and Zn, respectively, within 2km of the Zn smelter, decreasing to negligible levels after 47.1km downstream. Downstream of the smelter, groundwater-derived Zn contributed 54% of sediment Zn, whereas tailings contaminated sediments contributed 70% and 25% of Pb and Zn, respectively.

Identification of Plant Growth-Promoting Rhizobacteria for the Development of Probiotic Consortia

&#x0D; Soil infertility is one of the major challenges in agriculture. Although chemical fertilizers provide promising solution for crop growth in infertile soil, excessive application cause negative impacts on the natural systems such as soil and water. Moreover, these fertilizers can be converted into insoluble forms soon after application which often result in increasing the application frequency and the quantity. Hence, for decades plant growth-promoting rhizobacteria (PGPR) have been considered as an environmentally friendly alternative for chemical fertilizers. In this context, the present study was focused on the identification of candidate PGPRs for the development of probiotic packages for chilli (Capsicum annuum L.) which is one of the most widely grown and highly demanding vegetable crops in Sri Lanka. Rhizobacteria were isolated from the roots of healthy, young chilli plants grown in Angunakolapelessa, Sri Lanka and their rhizosphere soil. In total, 75 morphologically distinct strains were isolated, and they were inoculated into different nutrient media to screen their ability to solubilize insoluble mineral nutrient sources. Those media were National-Botanical-Research-Institute's phosphate agar [NBRIP-agar] with Ca3(PO4)2 as the P source, modified-Aleksandrov-agar containing mica as the K source and zinc-solubilizing-agar containing ZnCO3 as the Zn source. Further, bacteria were screened for N fixation in the nitrogen- fixing-bacteria (NfB) medium. Sixteen P-solubilizing-bacteria (PSB), 4 K-solubilizing-bacteria (KSB), 15 Zn-solubilizing-bacteria (ZnSB) and 10 N-fixing strains were identified. We noticed that all KSB strains also have the capacity to solubilize Ca3(PO4)2. All PSB strains, except CSTM10, can solubilize ZnCO3. The phosphate solubilizing index (PSI) was calculated to rank the P-solubilizing efficiency (PSE) of PSB. The highest PSI was found in CSTM40 and CSTM6. We further screened all mineral-solubilizing strains for the indole-3-acidic acid (IAA) production which is a PGP hormone. Cultures were induced for IAA production by supplementing the medium with 0.2% (w/v) tryptophan and IAA concentration was determined using the Salkowski's method. Nine strains were capable of producing IAA. The CSTM6 and CSTM21 showed the highest IAA production of&#x0D; 181.94 and 178.59 mg/L respectively. In conclusion, bacterial strains, CSTM6, CSTM14, CSTM21, CSTM24, CSTM40, CMTM1, CMTM2 and CSTM10 showed multiple PGP characteristics and they were selected as candidates for the developing probiotic consortia. They can be viewed as promising strains in sustainable agriculture since they perhaps can enhance the availability of mineral nutrients in soil and promote plant growth.&#x0D; &#x0D; Keywords: Biofertilizer, Capsicum annuum, Plant growth-promoting rhizobacteria&#x0D; &#x0D; Financial assistance from Indo-Sri Lanka Joint Research Programme 2019 funded by the State Ministry of Skill Development, Vocational Education, Research and Innovation, Sri Lanka is acknowledged.&#x0D;

Stability of grain zinc concentrations across lowland rice environments favors zinc biofortification breeding.

One-third of the human population consumes insufficient zinc (Zn) to sustain a healthy life. Zn deficiency can be relieved by increasing the Zn concentration ([Zn]) in staple food crops through biofortification breeding. Rice is a poor source of Zn, and in countries predominantly relying on rice without sufficient dietary diversification, such as Madagascar, Zn biofortification is a priority. Multi-environmental trials were performed in Madagascar over two years, 2019 and 2020, to screen a total of 28 genotypes including local and imported germplasm. The trials were conducted in the highlands of Ankazomiriotra, Anjiro, and Behenji and in Morovoay, a location representative of the coastal ecosystem. Contributions of genotype (G), environment (E), and G by E interactions (GEIs) were investigated. The grain [Zn] of local Malagasy rice varieties was similar to the internationally established grain [Zn] baseline of 18-20 μg/g for brown rice. While several imported breeding lines reached 50% of our breeding target set at +12 μg/g, only few met farmers' appreciation criteria. Levels of grain [Zn] were stable across E. The G effects accounted for a main fraction of the variation, 76% to 83% of the variation for year 1 and year 2 trials, respectively, while GEI effects were comparatively small, contributing 23% to 9%. This contrasted with dominant E and GEI effects for grain yield. Our results indicate that local varieties tested contained insufficient Zn to alleviate Zn malnutrition, and developing new Zn-biofortified varieties should therefore be a priority. GGE analysis did not distinguish mega-environments for grain [Zn], whereas at least three mega-environments existed for grain yield, differentiated by the presence of limiting environmental conditions and responsiveness to improved soil fertility. Our main conclusion reveals that grain [Zn] seems to be under strong genetic control in the agro-climatic conditions of Madagascar. We could identify several interesting genotypes as potential donors for the breeding program, among those BF156, with a relatively stable grain [Zn] (AMMI stability value (ASV) = 0.89) reaching our target (>26 μg/g). While selection for grain yield, general adaptation, and farmers' appreciation would have to rely on multi-environment testing, selection for grain [Zn] could be centralized in earlier generations.

Impact of Trace Mineral Source and Phytase Supplementation on Prececal Phytate Degradation and Mineral Digestibility, Bone Mineralization, and Tissue Gene Expression in Broiler Chickens

The objective of this study was to determine how different sources of Zn, Mn, and Cu in the feed without and with phytase affect prececal myo-inositol hexakisphosphate (InsP6) breakdown to myo-inositol (MI), prececal P digestibility, bone mineralization, and expression of mineral transporters in the jejunum of broiler chickens. A total of 896 male broiler chicks (Cobb 500) were distributed to 7 diets with 8 replicate pens (16 birds per floor pen). Experimental diets were fed from day 0 to 28. Diets were without or with phytase supplementation (0 or 750 FTU/kg) and were supplemented with three different trace mineral sources (TMS: sulfates, oxides, or chelates) containing 100 mg/kg Zn, 100 mg/kg Mn, and 125 mg/kg Cu. Prececal InsP6 disappearance and P digestibility were affected by interaction (phytase × TMS: P ≤ 0.010). In diets without phytase supplementation, prececal InsP6 disappearance and P digestibility were greater (P ≤ 0.001) in birds fed chelated minerals than in birds fed sulfates or oxides. However, no differences were observed between TMS in diets with phytase supplementation. Ileal MI concentration was increased by exogenous phytase but differed depending on TMS (phytase × TMS: P ≤ 0.050). Tibia ash concentration as well as Zn and Mn concentration in tibia ash were increased by phytase supplementation (P < 0.010), but the Cu concentration in tibia ash was not (P > 0.050). Gene expression of the assayed mineral transporters in the jejunum was not affected by diet (P > 0.050), except for Zn transporter 5 (phytase × TMS: P = 0.024). In conclusion, the tested TMS had minor effects on endogenous phytate degradation in the digestive tract of broiler chickens. However, in phytase-supplemented diets, the choice of TMS was not relevant to phytate degradation under the conditions of this study.

Higher heavy metal contamination indoors than outdoors during COVID-19 in Mexico City

People spend most of their time indoors, especially during the coronavirus disease. Prolonged exposure to heavy metal-contaminated dust can be harmful to human health. The objectives of this study were to identify the contamination level in outdoor and indoor dust, compare contamination in both environments, and assess the human health risk. Two-hundred thirty-nine samples of dust were taken by Mexico City citizens in 38 homes on the weekends of May 2020. Heavy metal concentrations were measured through XRF. The contamination level was set using the contamination factor with a local and global background value, mixed linear models were used to identify indoor and outdoor differences, and USEPA human health risk methodology was used. Pb, Zn, and Cu had the highest contamination levels, followed by Sr and Mn, using both the local and global background values. The Pb, Zn, and Cu contamination was greater indoors, while higher Mn, Sr, and Fe were detected outdoors. According to the outdoor/indoor ratios, the main sources of Ca, Pb, Zn, and Cu must be indoors, while the main sources of Fe, Mn, Sr, Y, and Ti are outdoors. A human health risk was not detected, as the hazard index was lower than one. However, ailments can be developed due to exposure to Pb, Mn, and Fe in children (hazard index > 0.1). A higher risk due to Pb exposition was found indoors. Indoor environments in Mexico City were more contaminated by heavy metals and represented a higher risk to human health than outdoors during the pandemic isolation.

Comparative efficacy of hydroxychloride and organic sources of zinc, copper, and manganese on egg production and concentration of trace minerals in eggs, plasma, and excreta in female broiler breeders from 42 to 63 weeks of age

Comparative efficacy of hydroxychloride (HC) and organic (OR) sources of Zn, Cu and Mn on performance of broiler breeders (BB) between 42 and 63 weeks of age (WOA) was investigated. A total of 408 ♀ Ross 708 and 48 ♂ Yield Plus cockerels were placed in pens (17 ♀ and 2 ♂) housed in 2 rooms (12 pens/room) and allocated to one of 2 diets in a completely randomized block design (n=12). The diets had similar nutrient specifications but differed in Zn, Cu, and Mn sources: 1) HO, a blend of 80% HC and 20% OR sources, and 2) OR, 100% OR sources. Birds were fed and managed according to breeder guidelines. The egg count was recorded daily and categorized as normal or abnormal. Egg yolk color, albumen height, Haugh unit, eggshell thickness, and eggshell breaking strength were assessed every 4 wk. Individual hen body weight (BW) was recorded at 5-wk intervals to determine BW uniformity. At 52 and 63 WOA, the eggs and excreta samples were collected. At the end of the trial, 4 hens per pen were bled for plasma concentration of trace minerals and organs (liver, gizzard, spleen, kidney, and thymus) weight. There were no interactions between source and age on any parameters (P > 0.05). There were no main effects of source on egg production, eggshell quality, BW, and organs weight (P > 0.05). Hens fed HO diets had darker yolk compared to those fed OR diets (P = 0.014). The concentration of Zn in the eggs of OR BB was higher (P = 0.022) than for HO birds. However, there were no dietary effects on the concentration of trace minerals in the egg, plasma, and excreta (P > 0.05). The results indicated that a mixture of HC and O as sources for Zn, Cu, and Mn was as effective as OR sources in supporting egg production, egg quality, and trace mineral utilization in broiler breeders.

Effects of Organic Zinc on the Growth Performance of Weanling Pigs: A Meta-analysis.

Supplementation of feed with organic zinc (Zn) has long been discussed as an alternative to inorganic Zn in pigs, but its effects on growth performance are mixed. This meta-analysis was conducted to provide a comprehensive evaluation of the influence of organic Zn on the growth performance of weanling pigs, on the basis of average daily gain (ADG), average daily feed intake (ADFI), and feed to gain ratio (F/G). We screened the PubMed and Web of Science databases (published before December 31, 2022; limited to English) systematically and contrasted organic Zn supplementation with inorganic Zn supplementation. There were 680 retrievals of studies, of which 16 (1389 pigs, 37 records) were eligible to analyze. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated using a random-effects model. The subgroup analysis was classified as organic Zn source (Zn-amino acid (Zn-AA), Zn-glycine (Zn-Gly), Zn-methionine (Zn-Met), Zn-Lysine (Zn-Lys), proteinate complex Zn (Zn-Pro), chitosan-Zn (Zn-CS) or Zn-lactate (Zn-Lac)) and Zn additive dose (low, medium, or high, i.e., lower than, equal to or higher than the requirement of NRC). Organic Zn addition in the weaning phase increased the ADG (P < 0.001) and the ADFI (P = 0.023) and decreased the F/G (P < 0.001). Specifically, for the organic sources, only Zn-CS supplementation presented significant effects on the ADG (P < 0.001), ADFI (P = 0.011), and F/G (P < 0.001). Moreover, medium-dose organic Zn supplementation had positive effects on ADG (P = 0.012), ADFI (P = 0.018), and F/G (P < 0.001). Our results indicate that organic Zn added to diets greatly improves the growth performance of weanling pigs.

Impacts of trace mineral source and ancillary drench on steer performance during a 60-day backgrounding phase

Nutritional approaches to optimize cattle health and performance during the receiving period are warranted. This experiment evaluated the impacts of supplementing organic complexed Cu, Co, Mn, and Zn on productive and health responses of high-risk beef cattle during a 60-day backgrounding phase. Crossbred steers (120) were purchased at auction and transported to the experimental facility, where BW was recorded (day−1; initial shrunk BW = 227.7 ± 1.3 kg). On day 0, steers were ranked by BW and allocated to one of eight groups and housed in drylot pens equipped with GrowSafe automated feeding systems (Model 8000; two bunks/pen). Groups were randomly assigned to receive a total mixed ration containing: (1) sulfate sources of Cu, Co, Mn, and Zn (INR; n = 40); (2) organic complexed sources of the same minerals (AAC; Zinpro Availa 4 based on a metal:amino acid complex ratio of 1:1 for Zn, Cu, and Mn in addition to cobalt glucoheptonate; Zinpro Corp., Eden Prairie, MN; n = 40); or (3) AAC and an organic complexed trace mineral drench (APF; 30 mL/hd; Zinpro ProFusion, Zinpro Corp.) on day 0 and with morbidity treatment (n = 40). Diets provided the same daily amount of all nutrients and minerals based on 7 g/steer daily of Zinpro Availa 4. Steers were assessed for bovine respiratory disease (BRD) signs daily. Liver biopsies were performed on days 0, 28 and 60. Blood samples were collected on days 0, 2, 6, 10, 13, 21, 28 and 45. No treatment differences were detected (P ≥ 0.23) for feed intake, final BW, average daily gain, or BRD incidence. Mean liver Co concentrations were greater (P = 0.02) in AAC and APF compared to INR steers. Mean liver Cu was greater (P = 0.02) in APF compared to AAC steers. Liver Zn tended to be greater (P = 0.10) on day 28 but less (P = 0.05) on day 60 for INR compared to AAC and APF steers. Plasma cortisol was lowest (P = 0.05) for AAC steers on day 6, whereas AAC steers tended to have greater (P = 0.09) plasma cortisol on day 13 compared with APF. Plasma haptoglobin tended to be greater (P ≤ 0.10) for INR steers on days 28 and 45 compared to AAC and APF. While supplementing cattle with AAC or INR results in similar animal performance and clinical disease, AAC and APF reduce stress and acute phase protein responses.

Influence of pre-weaning trace mineral exposure on subsequent performance and trace mineral status of beef calves during finishing

Objectives of these experiments were to 1) evaluate the accu­mulation of Co, Cu, Mn and Zn in liver tissue during the fin­ishing period of calves with or without previous mineral sup­plement exposure; and 2) evaluate the performance of calves provided either organic or inorganic sources of Co, Cu, Mn and Zn. One-hundred twenty steers of unknown mineral history, and 48 steers of known mineral history prior to weaning were comin­gled in experiment 1. Steers were allocated to pens and assigned to receive either an inorganic or organic trace minerals. For experiment 2, 83 steers with or without exposure to mineral supplements during gestation and the subsequent lactation, were utilized in a 181-d finishing experiment. ADG tended to be greater (P = 0.09) during the first 53 days on feed in calves provided organic trace minerals. Calves with trace mineral access prior to weaning were heavier at the time of feedlot arrival (P = 0.06), but not at slaughter (P = 0.37). Pro­viding access to mineral supplements to cow-calf pairs dur­ing grazing increased (P &lt; 0.01) Cu and Co, but did not affect (P ≥ 0.29) Zn or Mn concentrations at feedlot arrival. Liver Cu status improved during backgrounding in steers fed the or­ganic trace minerals. For calves of known mineral history, providing access to mineral sup­plements during grazing, prior to weaning, had no impacts on subsequent gain or intake during growing and finishing. Providing organic forms of trace minerals tended to improve growth early in the feeding period.&#x0D;

Accelerated export and transportation of heavy metals in watersheds under high geological backgrounds

The geological background level of metals plays a major role in mineral distribution and watershed diffuse heavy metal (HM) pollution. In this study, field research and a distributed hydrological model were used to analyze the distribution, sources, and pollution risk of watershed HMs in sediments with high geological HM backgrounds. Study showed that the mineral distribution and landcover promoted the transport differences of watershed HMs from upstream to the estuary. And the main sources of Co, Ni, and V in the estuarine sediments were natural sources. Sources of Pb and Zn were dominated by anthropogenic sources, accounting for 76% and 64% of their respective totals. The overall ecological risk of anthropogenically sourced HMs was dominated by Pb (46.6%), while the contributions of Co and Ni were also relatively high, accounting for 35.70% and 33.40%. Moreover, redundancy analysis showed that HM variations in the sediments were most sensitive to soil erosion and mineralizing rock distribution. The spatial patterns of watershed HMs from natural sources were significantly influenced by P loading, precipitation, and forest distribution. This combination of experiments and model improves the understanding of watershed HM variation and provides a new perspective for formulating effective watershed HM management strategies.

Fontes e níveis variados de zinco em rações para frangos de corte Ross 308: seu efeito no desempenho, na utilização de nutrientes, na morfologia intestinal e na composição microbiana

ABSTRACT Broilers (n=480) were used in an experiment designated for a 3(4 factorial arrangement to investigate the efficacy of three zinc (Zn) sources (organic Zn-Methionine, inorganic Zn sulphate and Zn oxide) and four inclusion rates (zero, 60, 120 and 180mg/kg of feed). Growth performance was not affect by Zn source in the entire of experimental period, however Zn level at 180 mg/kg improved body weight gain and feed conversion ratio compared to other Zn levels (P&lt;0.05). Inclusion of Zn-Methionine in the diet increased the population of Lactobacillus (P&lt;0.05), while E. coli counts decreased in birds which received Zn sulphate compared with Zn oxide group (P&lt;0.05). Inclusion 180 mg/kg of Zn decreased total intestinal aerobic bacteria in comparison to zero level (P&lt;0.05). An improvement of intestinal villus length and width was found in treatments supplemented with organic Zn (P&lt;0.05), Zn oxide increased intestinal crypt depth in birds as well (P&lt;0.05). Ileal digestibility of crude protein increased in broilers received Zn at 120 and 180 mg/kg compared with zero level (P&lt;0.05). Consequently, Zn-methionine supplement had an optimistic effect on the microbial population and intestinal morphometric variables. The level of 180mg/kg of supplemental Zn had beneficial influence on growth performance.

Egg Quality, Sensory Attributes, and Protein Metabolites of Laying Hens Fed Whole Flaxseed, Fish Oil, and Different Sources of Trace Elements.

This study evaluated the effects of whole flaxseed (WFS), fish oil (FO), and different sources of Se, Zn, and Fe (inorganic, organic, and nano-source) on egg production, quality, sensory attributes, and serum protein metabolites in laying hens. A total of 144 hens were divided into six groups with six replicates of four hens each. Hens were fed six diets as follows: 1) control diet; 2) 7.5%WFS+1.5%FO; 3) 7.5%WFS+1.5%FO+175 mg/kg vitamin E (VE); 4) 7.5%WFS+1.5%FO+175 mg/kg VE + inorganic sources of Se, Zn, and Fe (ISeZnFe); 5) 7.5%WFS+1.5%FO+175 mg/kg VE + organic sources of Se, Zn, and Fe (OSeZnFe); 6) 7.5%WFS+1.5%FO+175 mg/kg VE + nano-source of Se, Zn, and Fe (NSeZnFe) from 40-50 weeks of age. Laying hens fed 7.5% WFS, 1.5% FO, and different sources of trace elements in their diets had no negative effects on laying rate, egg weight, egg mass, feed intake, feed conversion ratio, body weight change, or survival rate compared to that of hens fed the control diet. Dietary treatments did not negatively affect the external and internal egg characteristics or egg sensory attributes. Feeding 7.5%WFS+1.5%FO+VE+ISeZnFe positively influenced yolk color in fresh eggs. Dietary treatments had a significant impact on egg nutritional composition, with the highest levels of macronutrients found in eggs from hens fed the 7.5%WFS+1.5%FO+VE+NSeZnFe treatment. The highest plasma globulin concentrations were observed in hens fed organic and nano-source trace elements. The same diets reduced plasma uric acid levels. Based on these findings, the inclusion of organic or nano-source trace minerals in diets containing WFS and FO positively affected egg quality and hen protein metabolites.

Differential effects of two Zn sources (ZnO nanoparticles and ZnSO4) on lipid metabolism via the ferroptosis pathway and SLC7A11K23 acetylation by HDAC8 and HDAC6 in a freshwater teleost

Understanding the toxicity and hazard risk of various metal sources is very important and can provide new insights for their risk evaluation in the environment.

Effect of dietary supplementation with zinc-methionine on ruminal enzyme activities, fermentation characteristics, methane production, and nutrient digestibility: An in vitro study.

The principal objective of this research was to examine the influence of zinc-methionine (Zn-Met) addition on feed on the in vitro ruminal enzyme activities, fermentation characteristics, methane production, and digestibilities of feed nutrients. The dosage of Zn-Met as a source of organic Zn was added to feed based on dry matter (DM) as follows: 0-without Zn addition (CON), 30 Zn mg/kg-low (LZM), 60 Zn mg/kg-medium (MZM), and 90 Zn mg/kg-high (HZM). The results indicated significant impacts of Zn-Met addition on various parameters. Compared to the CON group, all Zn-Met treatments resulted in increased total volatile fatty acids (VFA) (linear; p < 0.001), carboxymethyl-cellulase activity (linear; p < 0.001), and gas production at 48-h of incubation (linear; p < 0.001, quadratic; p < 0.001). Additionally, the MZM and HZM groups exhibited higher levels of amylase activity (linear; p < 0.001), protease activity (linear; p = 0.006), microbial protein (linear; p = 0.009), DM digestibility (linear; p < 0.001), organic matter (OM) digestibility (linear; p < 0.001), crude protein (CP) digestibility (linear; p = 0.004), and crude fiber (CF) digestibility (linear; p = 0.003) than CON treatment. However, the treatments did not have any noteworthy effects on pH, the individual VFA (acetate, propionate, and butyrate) proportions, NH3-N concentration, and methane production (p > 0.05). It could be summarized that supplementing 60 and 90 Zn mg/kg DM as Zn-Met could improve the in vitro ruminal enzyme activities, fermentation characteristics, and nutrient digestibility without affecting methane production.