Recent Advances in Understanding the Influence of Zinc, Copper, and Manganese on the Gastrointestinal Environment of Pigs and Poultry

Dietary zinc supplements: beneficial health effects and application in food, medicine and animals

Zinc, a crucial trace element is vital for the growth and development of humans. It is frequently described as 'the flower of life' and 'the source of intelligence'. Zinc supplements play a pivotal role in addressing zinc deficiency by serving as a vital source of this essential micronutrients, effectively replenishing depleted zinc levels in the body. In this paper, we first described the biological behavior of zinc in the human body and briefly described the physiological phenomena associated with zinc levels. The benefits and drawbacks of various zinc supplement forms are then discussed, with emphasis on the most recent zinc supplement formulations. Finally, the application of zinc supplements in food, medicine, and animal husbandry is further summarized. © 2024 Society of Chemical Industry.

A novel assessment of potentially toxic elements (PTEs) in water and sediment samples from the Indus River, Pakistan: An ecological risk assessment approach

Pakistan, a country with limited water resources and highly vulnerable to the adverse effects of climate change, faces numerous challenges in managing its water supply. In this sense, this study assessed potentially toxic elements (PTEs) in the surface water and sediments of Pakistan's Indus River and its tributaries. Key water quality parameters such as pH, electrical conductivity (EC), and total dissolved solids (TDS) were determined, with respective average values of 7.1, 40 μS/cm, and 208 mg L-1. The concentrations of Cd, Cr, Cu, Ni, and Zn in surface water samples averaged 26 μg L-1, 0.9 μg L-1, 1.4 μg L-1, 22 μg L-1, and 2.1 μg L-1, respectively. The general sediment PTE profile was Ni > Cd > Zn > Cu > Cr. Certain PTE levels exceeded recommended thresholds, indicating the establishment of environmental pollution. Calculated geo-accumulation index values suggested moderate to heavy pollution levels in sediment, with PERI (404) values reinforcing the ecological risk posed by elevated PTE concentrations. Furthermore, significant correlations were observed between specific PTE pairs in both water and sediment samples. This study contributes with novel insights into the distribution and ecological implications of PTE contamination in the Indus River and its tributaries, paving the way for ecological risk management efforts.

Impact of diet change on the gut microbiome of common marmosets (Callithrix jacchus)

Gastrointestinal diseases are the most frequently reported clinical problems in captive common marmosets (Callithrix jacchus), often affecting the health and welfare of the animal and ultimately their use as a research subject. The microbiome has been shown to be intimately connected to diet and gastrointestinal health. Here, we use shotgun metagenomics and untargeted metabolomics in fecal samples of common marmosets collected before, during, and after a dietary transition from a biscuit to a gel diet. The overall health of marmosets, measured as weight recovery and reproductive outcome, improved after the diet transition. Moreover, each marmoset pair had significant shifts in the microbiome and metabolome after the diet transition. In general, we saw a decrease in Escherichia coli and Prevotella species and an increase in Bifidobacterium species. Untargeted metabolic profiles indicated that polyamine levels, specifically cadaverine and putrescine, were high after diet transition, suggesting either an increase in excretion or a decrease in intestinal reabsorption at the intestinal level. In conclusion, our data suggest that Bifidobacterium species could potentially be useful as probiotic supplements to the laboratory marmoset diet. Future studies with a larger sample size will be beneficial to show that this is consistent with the diet change.

IMPORTANCE

Appropriate diet and health of the common marmoset in captivity are essential both for the welfare of the animal and to improve experimental outcomes. Our study shows that a gel diet compared to a biscuit diet improves the health of a marmoset colony, is linked to increases in Bifidobacterium species, and increases the removal of molecules associated with disease. The diet transition had an influence on the molecular changes at both the pair and time point group levels, but only at the pair level for the microbial changes. It appears to be more important which genes and functions present changed rather than specific microbes. Further studies are needed to identify specific components that should be considered when choosing an appropriate diet and additional supplementary foods, as well as to validate the benefits of providing probiotics. Probiotics containing Bifidobacterium species appear to be useful as probiotic supplements to the laboratory marmoset diet, but additional work is needed to validate these findings.

Novel feed additive delivers antimicrobial copper and influences fecal microbiota in pigs

Dehydrated alginate beads formulated with copper were synthesized and tested as a feed additive to influence the microbiota in finishing pigs and potentially use them as a preharvest intervention to reduce fecal pathogen shedding. The efficacy of the copper beads was tested in vitro and in vivo. In vitro, Salmonella was significantly (P < 0.05) reduced when in contact with the copper beads solution for up to 6 h, with a 5.4 log CFU/mL reduction over the first hour. Chemical analysis of the soak solutions demonstrated the beads delivered their copper payload gradually over the same period the bactericidal effect was observed. For the in vivo experiments, pigs (n = 48) supplemented with the copper beads experienced significant shifts in their microbiota. Enterobacteriaceae (EB) increased by 1.07 log CFU/g (P < 0.05), while lactic acid bacteria (LAB) decreased by 1.22 log CFU/g (P < 0.05) during the treatment period. When beads were removed from the feed, EB and LAB concentrations returned to baseline, indicating copper beads led to measurable and significant changes in microbial loads. Fecal microbiome analysis conducted to explore additional changes by copper bead supplementation demonstrated that, at the phylum level, there was an increase in Firmicutes, Euryarchaeota, and Acidobacteriota, while at the genus level, an increase in Methanosphaera and Pseudomonas was observed. Measures of copper in swine feces showed values ~20 times higher in the treatment group than in the control group during the treatment period, suggesting that dehydrated alginate copper beads were effective in delivering antimicrobial copper to the animal hindgut.IMPORTANCECopper has long been known to have antimicrobial properties. However, when water-soluble salts are fed to livestock, the copper may rapidly dissolve in gastric contents and fail to reach the gut. Here, specially formulated copper beads are seamlessly incorporated into feed and allow copper to remain longer in the gastrointestinal tract of animals, reach deep into both the foregut and hindgut, and shift microbial populations. The technology delivers antimicrobial copper to the animal hindgut and potentially reduces pathogenic microorganisms before animal slaughter.

Multi-omics unveils tryptophan metabolic pathway as a key pathway influencing residual feed intake in Duroc swine

The genetic trait of residual feed intake (RFI) holds considerable importance in the swine industry. Recent research indicates that the gut microbiota of pigs plays a pivotal role in the manifestation of the RFI trait. Nevertheless, the metabolic pathways involved in the functioning of these microorganisms remain elusive. Thus, based on the ranking of the RFI trait in Duroc pigs, the present study selected the top 10 and bottom 10 pigs as the experimental subjects. The distribution and metabolite differences of cecal microbiota were analyzed using 16S rRNA gene sequencing and liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques. The low RFI cecal group was named LRC, and the high RFI cecal group was named HRC. The results indicate that the LRC group had lower RFI, feed conversion ratio (FCR), average daily feed intake (ADFI) (p < 0.001), and thinner backfat (p < 0.05) compared with the HRC group. We simultaneously recorded the foraging behavior as well, the LRC group had a significant increase in total time spent at the feeder per day (TPD) (p < 0.05) and a significant increase in average feed intake per mins (AFI) and the number of visits to the feeder per day (NVD) compared to the HRC group (p < 0.001). Clostridium_XVIII, Bulleidia, and Intestinimonas were significantly enriched in the LRC group (p < 0.01), while Sutterella, Fusobacterium, and Bacteroides were significantly increased in the HRC group (p < 0.01). In the metabolome, we detected 390 (248 metabolites up and 142 down in the LRC compared with HRC), and 200 (97 metabolites up and 103 down in the LRC compared with HRC) differential metabolites in positive and negative ionization modes. The comprehensive analysis found that in the LRC group, Escherichia and Eubacterium in the gut may increase serotonin content, respectively. Bacteroides may deplete serotonin. We suggest that the RFI may be partly achieved through tryptophan metabolism in gut microbes. In individuals with low RFI, gut microbes may enhance feed efficiency by enhancing host synthesis and metabolism of tryptophan-related metabolites.

Comparative Effects of Including Inorganic, Organic, and Hydroxy Zinc Sources on Growth Development, Egg Quality, Mineral Excretion, and Bone Health of Laying Quails

The purpose of this study was to determine the effects of the dietary addition of zinc (Zn) in the form of sulphate (Zn-S), glycine (Zn-G), and hydroxychloride (Zn-H) on quail performance, eggshell quality, antioxidant status, mineral excretion, biomechanical properties and mineralization of bone. A total of 75 female quails (10-weeks-old) were randomly distributed into 3 groups with 5 replications, each with 5 female quails. Treatment groups were set up by adding Zn-S and Zn-H as the inorganic form and Zn-G as the organic form of zinc to the corn-soybean basal diet (34.14 mg/kg Zn) to obtain 50 mg/kg Zn and the feeding experiment lasted for 12 weeks. Performance parameters and egg production were not impaired by the Zn source (P > 0.05). The inclusion of Zn-S in the diet produced a reduction in eggshell thickness, while an improvement in yolk antioxidant capacity (measured as MDA concentration) was detected compared to the other Zn sources (P < 0.05). Shear strength and cortical bone area increased (P < 0.05) with Zn-G supplementation, however, the mineral concentration of the tibia was higher (P < 0.01) in those quails who had received Zn-H. Lower levels of mineral excretion were observed in both types of supplementations compared to Zn-S. Therefore, it can be stated that Zn-G or Zn-H supplementation in the diet of laying quails could be an interesting strategy to reduce mineral excretion and improve bone mineralization without affecting performance compared to Zn-S. However, further studies are needed to determine the differences between Zn-G and Zn-H.

Impact of zinc supplementation on phenotypic antimicrobial resistance of fecal commensal bacteria from pre-weaned dairy calves

The objective of this study was to evaluate the impact of dietary zinc supplementation in pre-weaned dairy calves on the phenotypic antimicrobial resistance (AMR) of fecal commensal bacteria. A repository of fecal specimens from a random sample of calves block-randomized into placebo (n = 39) and zinc sulfate (n = 28) groups collected over a zinc supplementation clinical trial at the onset of calf diarrhea, calf diarrheal cure, and the last day of 14 cumulative days of zinc or placebo treatment were analyzed. Antimicrobial susceptibility testing was conducted for Enterococcus spp. (n = 167) and E. coli (n = 44), with one representative isolate of each commensal bacteria tested per sample. Parametric survival interval regression models were constructed to evaluate the association between zinc treatment and phenotypic AMR, with exponentiated accelerated failure time (AFT) coefficients adapted for MIC instead of time representing the degree of change in AMR (MIC Ratio, MR). Findings from our study indicated that zinc supplementation did not significantly alter the MIC in Enterococcus spp. for 13 drugs: gentamicin, vancomycin, ciprofloxacin, erythromycin, penicillin, nitrofurantoin, linezolid, quinupristin/dalfopristin, tylosin tartrate, streptomycin, daptomycin, chloramphenicol, and tigecycline (MR = 0.96-2.94, p > 0.05). In E. coli, zinc supplementation was not associated with resistance to azithromycin (MR = 0.80, p > 0.05) and ceftriaxone (MR = 0.95, p > 0.05). However, a significant reduction in E. coli MIC values was observed for ciprofloxacin (MR = 0.17, 95% CI 0.03-0.97) and nalidixic acid (MR = 0.28, 95% CI 0.15-0.53) for zinc-treated compared to placebo-treated calves. Alongside predictions of MIC values generated from these 17 AFT models, findings from this study corroborate the influence of age and antimicrobial exposure on phenotypic AMR.

Dietary collagen peptide-chelated trace elements supplementation for breeder hens improves the intestinal health of chick offspring

BACKGROUND

Dietary supplementation with trace elements zinc (Zn), iron (Fe) and manganese (Mn) could promote intestinal development and improve intestinal health. There are, however, few studies examining the possibility that maternal original Zn, Fe and Mn could regulate intestinal development and barrier function in the offspring. This study aimed to investigate how the intestinal growth and barrier function of breeder offspring were affected by collagen peptide-chelated trace elements (PTE; Zn, Fe, Mn).

RESULTS

PTE supplementation in the diet of breeder hens increased the concentrations of Zn, Fe and Mn in egg yolk. Maternal PTE supplementation improved morphological parameters of the intestine (villi height, crypt depth and villi height/crypt depth) and upregulated the mRNA expression level of leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) in the ileum of chick embryos. Furthermore, maternal PTE effect improved villi height/crypt depth of offspring at 1 and 14 days of age, and upregulated Lgr5, Claudin-3 and E-cadherin mRNA expression in the broiler ileum. Additionally, PTE treatment could enhance the intestinal microbial diversity of offspring. Maternal PTE supplementation increased the relative abundance of Clostridiales at the genus level and decreased the relative abundance of Enterococcus in newborn offspring. Moreover, maternal PTE supplementation ameliorated the elevated nuclear factor kappa B, toll-like receptor 4 and interleukin 1β mRNA expression in the ileum of offspring caused by LPS challenge.

CONCLUSION

Maternal PTE supplementation could promote intestinal development and enhance the intestinal barrier function of chicken offspring. © 2023 Society of Chemical Industry.

Estimating the geographical patterns and health risks associated with PM2.5-bound heavy metals to guide PM2.5 control targets in China based on machine-learning algorithms

PM2.5 is the main component of haze, and PM2.5-bound heavy metals (PBHMs) can induce various toxic effects via inhalation. However, comprehensive macroanalyses on large scales are still lacking. In this study, we compiled a substantial dataset consisting of the concentrations of eight PBHMs, including As, Cd, Cr, Cu, Mn, Ni, Pb and Zn, across different cities in China. To improve prediction accuracy, we enhanced the traditional land-use regression (LUR) model by incorporating emission source-related variables and employing the best-fitted machine-learning algorithm, which was applied to predict PBHM concentrations, analyze geographical patterns and assess the health risks associated with metals under different PM2.5 control targets. Our model exhibited excellent performance in predicting the concentrations of PBHMs, with predicted values closely matching measured values. Noncarcinogenic risks exist in 99.4% of the estimated regions, and the carcinogenic risks in all studied regions of the country are within an acceptable range (1 × 10-5-1 × 10-6). In densely populated areas such as Henan, Shandong, and Sichuan, it is imperative to control the concentration of PBHMs to reduce the number of patients with cancer. Controlling PM2.5 effectively decreases both carcinogenic and noncarcinogenic health risks associated with PBHMs, but still exceed acceptable risk level, suggesting that other important emission sources should be given attention.

Upcycling of recycled minerals from sewage sludge through black soldier fly larvae (Hermetia illucens): Impact on growth and mineral accumulation

Phosphorous (P) resources are finite. Sewage sludge recyclates (SSR) are not only of interest as plant fertilizer but also as potential source of minerals in animal nutrition. However, besides P and calcium (Ca), SSR contain heavy metals. Under EU legislation, the use of SSR derivatives in animal feed is not permitted, but given the need to improve nutrient recycling, it could be an environmentally sound future mineral source. Black soldier fly larvae (BSFL) convert low-grade biomass into valuable proteins and lipids, and accumulate minerals in their body. It was hypothesized that BSFL modify and increase their mineral content in response to feeding on SSR containing substrates. The objective was to evaluate the upcycling of minerals from SSR into agri-food nutrient cycles through BSFL. Growth, nutrient and mineral composition were compared in BSFL reared either on a modified Gainesville fly diet (FD) or on FD supplemented with either 4% of biochar (FD + BCH) or 3.6% of single-superphosphate (FD + SSP) recyclate (n = 6 BSFL rearing units/group). Larval mass, mineral and nutrient concentrations and yields were determined, and the bioaccumulation factor (BAF) was calculated. The FD + SSP substrate decreased specific growth rate and crude fat of BSFL (P < 0.05) compared to FD. The FD + SSP larvae had higher Ca and P contents and yields but the BAF for Ca was lowest. The FD + BCH larvae increased Ca, iron, cadmium and lead contents compared to FD. Larvae produced on FD + SSP showed lower lead and higher arsenic concentration than on FD + BCH. Frass of FD + BCH had higher heavy metal concentration than FD + SSP and FD (P < 0.05). Except for cadmium and manganese, the larval heavy metal concentration was below the legally permitted upper concentrations for feed. In conclusion, the SSR used could enrich BSFL with Ca and P but at the expense of growth. Due to the accumulation of Cd and Mn, BSFL or products thereof can only be a component of farmed animal feed whereas in BSFL frass heavy metal concentrations remained below the upper limit authorized by EU.

Crosstalk between trace elements and T-cell immunity during early-life health in pigs

With gradual ban on the use of antibiotics, the deficiency and excessive use of trace elements in intestinal health is gaining attention. In mammals, trace elements are essential for the development of the immune system, specifically T-cell proliferation, and differentiation. However, there remain significant gaps in our understanding of the effects of certain trace elements on T-cell immune phenotypes and functions in pigs. In this review, we summarize the specificity, development, subpopulations, and responses to pathogens of porcine T cells and the effects of functional trace elements (e.g., iron, copper, zinc, and selenium) on intestinal T-cell immunity during early-life health in pigs. Furthermore, we discuss the current trends of research on the crosstalk mechanisms between trace elements and T-cell immunity. The present review expands our knowledge of the association between trace elements and T-cell immunity and provides an opportunity to utilize the metabolism of trace elements as a target to treat various diseases.

From Farm to Fork: Persistence of Clinically Relevant Multidrug-Resistant and Copper-Tolerant Klebsiella pneumoniae Long after Colistin Withdrawal in Poultry Production

Concerns about colistin-resistant bacteria in animal food-environmental-human ecosystems prompted the poultry sector to implement colistin restrictions and explore alternative trace metals/copper feed supplementation. The impact of these strategies on the selection and persistence of colistin-resistant Klebsiella pneumoniae in the whole poultry production chain needs clarification. We assessed colistin-resistant and copper-tolerant K. pneumoniae occurrence in chickens raised with inorganic and organic copper formulas from 1-day-old chicks to meat (7 farms from 2019 to 2020), after long-term colistin withdrawal (>2 years). Clonal diversity and K. pneumoniae adaptive features were characterized by cultural, molecular, and whole-genome-sequencing (WGS) approaches. Most chicken flocks (75%) carried K. pneumoniae at early and preslaughter stages, with a significant decrease (P < 0.05) in meat batches (17%) and sporadic water/feed contamination. High rates (>50%) of colistin-resistant/mcr-negative K. pneumoniae were observed among fecal samples, independently of feed. Most samples carried multidrug-resistant (90%) and copper-tolerant (81%; silA and pcoD positive and with a MICCuSO4 of ≥16 mM) isolates. WGS revealed accumulation of colistin resistance-associated mutations and F type multireplicon plasmids carrying antibiotic resistance and metal/copper tolerance genes. The K. pneumoniae population was polyclonal, with various lineages dispersed throughout poultry production. ST15-KL19, ST15-KL146, and ST392-KL27 and IncF plasmids were similar to those from global human clinical isolates, suggesting chicken production as a reservoir/source of clinically relevant K. pneumoniae lineages and genes with potential risk to humans through food and/or environmental exposure. Despite the limited mcr spread due to the long-term colistin ban, this action was ineffective in controlling colistin-resistant/mcr-negative K. pneumoniae, regardless of feed. This study provides crucial insights into the persistence of clinically relevant K. pneumoniae in the poultry production chain and highlights the need for continued surveillance and proactive food safety actions within a One Health perspective. IMPORTANCE The spread of bacteria resistant to last-resort antibiotics such as colistin throughout the food chain is a serious concern for public health. The poultry sector has responded by restricting colistin use and exploring alternative trace metals/copper feed supplements. However, it is unclear how and to which extent these changes impact the selection and persistence of clinically relevant Klebsiella pneumoniae throughout the poultry chain. We found a high occurrence of copper-tolerant and colistin-resistant/mcr-negative K. pneumoniae in chicken flocks, regardless of inorganic and organic copper formulas use and a long-term colistin ban. Despite the high K. pneumoniae isolate diversity, the occurrence of identical lineages and plasmids across samples and/or clinical isolates suggests poultry as a potential source of human K. pneumoniae exposure. This study highlights the need for continued surveillance and proactive farm-to-fork actions to mitigate the risks to public health, relevant for stakeholders involved in the food industry and policymakers tasked with regulating food safety.

Worldwide Research Trends for Chelates in Animal Science: A Bibliometric Analysis

The purpose of this study was to look at research trends in the application of CTM in animal nutrition in order to identify current and emerging challenges, as well as to examine the intellectual structure of the subject. The intellectual structure of CTM was examined using keyword and reference analysis. The research community includes all research and review articles published in journals indexed in the Web of Science database during the years 1990-2022. The results showed that the terms zinc, co-occurring 331 times, performance (324 times), and copper 216 (times) were the main and hotspots of research in the field of chelate. The data suggest that the most important keywords during the study period were zinc, copper, pig, bovine, metabolism, and bioavailability. The terms health, muscle, beef, trace elements, and dietary supplements represent emerging topics in CTM, as research began to focus on these areas during the years 2017-2022. The country with the greatest number of published articles was the United States of America. This bibliometric analysis showed that countries are focusing on the effects of CTM on the health and musculature of cattle through dietary supplementation with trace elements. According to the identified hot and emerging topics, this research can serve as a roadmap for a global comprehensive scientific plan and policy.

Integrated evaluation of the requirements and excretions of Cu, Fe, Zn, and Mn for broilers via a uniform design method

This study aimed to determine the ideal balance profile of Cu, Fe, Zn, and Mn for broilers of 1-21 days of age via a uniform experimental design. In Experiment 1, 900 1-day-old Arbor Acres male broilers were randomly allotted to 15 dietary treatments with six replicates of 10 birds. A total of 14 experimental diets were formulated with the supplementation of 8~16, 123~160, 40~80, and 60~120 mg/kg of Cu, Fe, Zn, and Mn, respectively, in the basal diet, according to the uniform design method. The excretion of Cu, Fe, Zn, and Mn in the manure and the broiler performance were determined to build the ideal balance profile of these elements. Experiment 2 was conducted based on the ideal balance profile built in Experiment 1, to test its practicability using 720 broilers with two treatments. The dietary concentrations of Cu, Fe, Zn, and Mn in the control group were 15.19, 203.08, 76.78, and 86.13 mg/kg, respectively. In Experiment 1, the concentrations of Cu, Fe, Zn, and Mn in the diets were 16.96, 166.66, 46.01, and 60.26 mg/kg, respectively, when the average daily gain reached the optimum value. When the dietary concentrations of Cu, Fe, Zn, and Mn were 8.54, 130.66, 38.19, and 64.07 mg/kg, respectively, the total excretion of Cu, Fe, Zn, and Mn got the minimum value. There are corresponding ideal balance profiles for minimum excretion of a certain element. In Experiment 2, the dietary levels of Fe, Zn, and Mn were decreased by 17.93%, 40.08%, and 30.04%, respectively, which had no significant effect on average daily gain, average daily feed intake, and feed gain for 1~21 day-old broilers but markedly decreased the excretion of Cu and Mn and total excretion. It was concluded that there is a dilemma between growth performance and mineral excretion. Although dietary levels of Cu, Fe, Zn, and Mn supporting optimal growth are higher than those for minimizing mineral excretion, supplementing too many trace elements in the diets of broilers is unnecessary.

Evaluation of a dacitic (rhyolitic) tuff breccia use on performance, inflammatory, and antioxidant responses in broilers mildly challenged with Eimeria spp

The objective of the study was to investigate the effects of a dacitic tuff breccia (DTB) on Eimeria-infected broilers. A total of 600 one-day-old Cobb 500 male chickens were randomly assigned to 5 treatments with 10 replicates of 12 birds. Treatments were: an unchallenged control (UC), a challenged (CC) control (0% DTB), and 3 challenged groups with 0.125, 0.25, or 0.5% DTB. At d 14, birds in the CC and DTB groups were orally gavaged with mixed Eimeria spp., while the UC received water. Growth performance was evaluated during prechallenge, challenge, and postchallenge periods (0-14 d; 14-20 d; and 20-26 d, respectively). Gastrointestinal permeability was measured at 5 days postinfection (dpi). Intestinal histology and nutrient digestibility of dry matter (DM), crude protein (CP), and ileal digestible energy (IDE) were measured at 6 dpi. Liver activity of glutathione peroxidase (GSH-Px) was determined at 6 dpi, and concentrations of reduced (GSH) and oxidized glutathione (GSSG) were analyzed at 6 and 12 dpi. Data were analyzed using a linear mixed model analysis and Tukey's test (P ≤ 0.05). From 0 to 14 d, similar average daily gain (ADG) and average daily feed intake (ADFI, P > 0.05) were observed. Gain:feed ratio (GF) was higher in 0.125, 0.25, and 0.5% of DTB than the CC and UC (P < 0.001). From 14 to 20 d, the UC had the highest ADG, ADFI, and GF (P < 0.001). At 5 dpi, intestinal permeability was higher in the challenged groups than the UC. Additionally, the UC showed the highest apparent ileal digestibility of CP, whereas 0.125% DTB had higher CP digestibility than the CC and 0.5% DTB (P < 0.001). At 6 dpi, 0.125% DTB increased GSH-Px activity compared to the CC, 0.5% DTB, and UC (P < 0.001). At 12 dpi, 0.125% DTB showed increased GSH concentration compared to the CC, 0.25% DTB, and 0.5% DTB (P < 0.01). The mild coccidia infection negatively impacted growth performance, apparent ileal nutrient digestibility, intestinal histology, and gastrointestinal integrity in broilers. The use of 0.125% DTB exhibited potential in improving antioxidant responses, apparent ileal digestibility of CP, and growth performance.

Effects of Different Levels of Organic Trace Minerals on Oxidative Status and Intestinal Function in Weanling Piglets

An experiment was conducted to compare the effects of replacing inorganic trace minerals (ITM) with different levels of complex organic trace minerals (OTM) on the growth performance, oxidative status, and intestinal function of piglets. Weanling piglets were assigned to five groups: a control group fed a basal diet supplemented with inorganic trace minerals and the other four groups fed basal diets supplemented with different levels of OTMs. The results showed that diets supplemented with 50 ppm Fe, 30 ppm Zn, 15 ppm Mn, and 0.2 ppm Se from OTM (L-OTM), or with 75 ppm Fe, 45 ppm Zn, 22.5 ppm Mn, and 0.3 ppm Se from OTM (M-OTM) significantly decreased the diarrhea ratio in the piglets compared with those supplemented with 100 ppm Fe, 90 ppm Zn, 40 ppm Mn, and 0.4 ppm Se from ITM. Compared with those in the ITM group, the piglets in the M-OTM group had significantly higher serum CuZnSOD, MnSOD, and GSH-Px levels. Moreover, piglets in the L-OTM and M-OTM groups had higher Sod and Gpx gene expression than those in the ITM group. Additionally, piglets in the L-OTM and M-OTM groups had significantly higher villus height than those in the ITM group, and the M-OTM group piglets had lower serum diamine oxidase content and higher ileal ZO-1 and occludin protein expression levels than those in the ITM group. These results indicate that replacing dietary ITMs with OTMs could decrease diarrhea occurrence and improve the oxidative status and intestinal barrier function in weanling piglets.

Dietary trace mineral pattern influences gut microbiota and intestinal health of broilers

Dietary trace minerals can impact gut flora, which can further affect intestinal health. However, the dietary balance pattern of trace minerals for the intestinal health of broilers needs to be explored. The present study was conducted to investigate the effect of the dietary pattern of Cu, Fe, Mn, Zn, and Se on the intestinal morphology, microbiota, short-chain fatty acid concentrations, antioxidant status, and the expression of tight junction proteins in broilers. A total of 240 1-d-old Arbor Acres male broilers were randomly assigned to one of five treatments with six replicate cages of eight birds per cage for each treatment. The birds were fed the corn-soybean meal basal diet supplemented with five combination patterns of trace minerals for 42 d. The dietary treatments were as follows: the inorganic sources were added to the diet based on the recommendations of the current National Research Council (NRC, T1) and Ministry of Agriculture of P.R. China (MAP) (T2) for broiler chicks, respectively; the inorganic sources were added to the diet at the levels based on our previous results of inorganic trace mineral requirements for broilers (T3); the organic sources were added to the diet at the levels considering the bioavailabilities of organic trace minerals for broilers described in our previous studies (T4); and the organic sources were added to the diet based on the recommendations of the current MAP for broiler chicks (T5). The results showed that broilers from T1 had lower (P < 0.05) crypt depth (CD), and a higher (P < 0.05) villus height: CD in duodenum on day 21 and lower CD (P < 0.05) in jejunum on day 42 than those from T3 and T4. Broilers from T1, T3, and T5 had a higher (P < 0.05) Shannon index in cecum on day 21 than those from T4. Broilers from T1 had a higher (P < 0.05) abundance of Lactobacillus in ileum on day 21 than those from T2 and T3. Broilers from T1, T2, and T5 had a higher (P < 0.05) valeric acid concentrations in cecum on day 42 than those from T3 and T4. In addition, Birds from T2 had higher (P < 0.05) Claudin-1 mRNA levels in jejunum on day 42 than those from T3 and T4. And birds from T3, T4, and T5 had a higher (P < 0.05) Occludin protein expression levels in duodenum on day 42 than those from T2. These results indicate that dietary pattern of Cu, Fe, Mn, Zn, and Se influenced gut flora and intestinal health of broilers, and the appropriate pattern of Cu, Fe, Mn, Zn, and Se in the diet for intestinal health of broilers would be Cu 12 mg, Fe 229 mg, Mn 81 mg, Zn 78 mg, and Se 0.24 mg/kg (1 to 21 d of age), and Cu 11 mg, Fe 193 mg, Mn 80 mg, Zn 73 mg, and Se 0.22 mg/kg (22 to 42 d of age), when the trace minerals as inorganic sources were added to diets according to the recommendations of the current NRC.

Effects of supplementation of inorganic trace elements with organic trace elements chelated with hydroxy methionine on laying performance, egg quality, blood micronutrients, antioxidant capacity and immune function of laying ducks

Introduction

This study aimed to investigate the effects of organic trace elements chelated with hydroxy methionine (OTE-HM) in diets, which substituted inorganic trace elements, on laying performance, egg quality, blood microelement content, antioxidant capacity and immune function of laying ducks.

Methods

A total of 300 healthy laying ducks at age of 30 wk were randomly divided into 5 treatments and 10 ducks per replicate. The treatments included a control group (CON) which was served with basal diet supplemented with 20 mg/kg Cu, 50 mg/kg Fe, 70 mg/kg Mn, and 70 mg/kg Zn in inorganic form, and 4 OTE-HM treated groups (OTE-HM25, OTE-HM50, OTE-HM75, OTE-HM100) which were served with basal diets supplemented with OTE-HM providing trace elements (combination of Cu, Fe, Mn, Zn) at 25%, 50%, 75% and 100% of the commercial levels, respectively.

Results

Results showed that substitution of inorganic trace elements with OTE-HM did not affect egg production, qualified egg rate, average egg weight, average daily egg mass, average daily feed intake, or feed per kg egg of laying ducks (P &gt; 0.05). Dietary with OTE-HM did not influence eggshell strength, eggshell thickness, egg shape index, eggshell ratio, yolk ratio, albumen ratio, albumen height, and Haugh unit of the sampled eggs of ducks (P &gt; 0.05), but increased the yolk color, compared with dietary with inorganic trace elements (P&lt; 0.01). Moreover, the blood content of Cu of the laying ducks was significantly increased by OTE-HM compared with that in CON (P&lt; 0.001), but the other elements in laying duck blood were not different among treatments (P &gt; 0.05). OTE-HM (75% and 100%) significantly increased serum activities of glutathione peroxidase and Cu-Zn superoxide dismutase, and decreased serum content of malonaldehyde of laying ducks compared with those in CON (P&lt; 0.05). OTE-HM (50%, 75%, and 100%) significantly increased the serum contents of immunoglobulin G and immunoglobulin A of laying ducks compared with those in CON (P&lt; 0.05).

Discussion

Collectively, replacing inorganic trace elements with 50% and 75% OTE-HM in diets did not influence the laying performance or egg quality, but improved trace element efficacy, antioxidant capacity and immune function of the laying ducks.

Relative Bioavailability of Trace Minerals in Production Animal Nutrition: A Review

The importance of dietary supplementation of animal feeds with trace minerals is irrefutable, with various forms of both organic and inorganic products commercially available. With advances in research techniques, and data obtained from both in-vitro and in-vivo studies in recent years, differences between inorganic and organic trace minerals have become more apparent. Furthermore, differences between specific organic mineral types can now be identified. Adhering to PRISMA guidelines for systematic reviews, we carried out an extensive literature search on previously published studies detailing performance responses to trace minerals, in addition to their corresponding relative bioavailability values. This review covers four of the main trace minerals included in feed: copper, iron, manganese and zinc, and encompasses the different types of organic and inorganic products commercially available. Their impact from environmental, economic, and nutritional perspectives are discussed, along with the biological availability of various mineral forms in production animals. Species-specific sections cover ruminants, poultry, and swine. Extensive relative bioavailability tables cover values for all trace mineral products commercially available, including those not previously reviewed in earlier studies, thereby providing a comprehensive industry reference guide. Additionally, we examine reasons for variance in reported relative bioavailability values, with an emphasis on accounting for data misinterpretation.

Determination of the Optimal Level of Dietary Zinc for Newly Weaned Pigs: A Dose-Response Study

Simple Summary

Piglets have a very low feed intake immediately after weaning. We hypothesise that the EU-legislated maximum dietary zinc concentration (150 mg zinc/kg diet) will increase the risk of zinc deficiency after weaning. Zinc deficiency includes symptoms such as impaired growth and increased risk of diarrhoea. However, a high dietary zinc concentration has an antimicrobial effect on the bacteria and increases the risk of antimicrobial resistance. The findings of this study show that the dietary zinc level had a quadratic effect on growth, with a turning point at an approximately 1400 mg zinc per kg diet. The risk of diarrhoea increased up to 60% for pigs that had a blood zinc concentration which decreased after weaning. Maintaining the blood zinc concentration seven days after weaning required up to 1121 mg zinc per kg diet. There was no evidence for an antimicrobial effect when feeding pigs a diet with up to 1601 mg zinc per kg.

Abstract

One hundred and eighty individually housed piglets with an initial body weight of 7.63 ± 0.98 kg (at 28 days of age) were fed a diet containing either 153, 493, 1022, 1601, 2052 or 2407 mg zinc/kg (added Zn as zinc oxide; ZnO) from day 0–21 post weaning to determine the optimal level of Zn for weaned piglets. Body weight, feed intake and faecal scores were recorded, and blood and faecal samples were collected. Dietary Zn content quadratically affected both feed intake and gain in the first two weeks, with an approximately 1400 mg Zn/kg diet and a Zn intake of 400 mg/day as the optimal levels. The relative risk of diarrhoea increased up to 60% at day 7 and 14 if serum Zn status dropped below the weaning level (767 µg/L), and maintain the weaning serum Zn status required approximately 1100 mg Zn/kg (166 mg Zn/day) during week 1. Blood markers of intestinal integrity (D-lactate and diamine oxidase) were unaffected by dietary Zn, and dietary Zn levels of 1022 and 1601 mg/kg did not affect the faecal numbers of total bacteria, Lactobacilli and E. Coli bacteria compared to 153 mg Zn/kg. These results indicate that the requirement for Zn in newly weaned piglets may be substantially higher than currently assumed.

Importance of Zinc Nanoparticles for the Intestinal Microbiome of Weaned Piglets

The scientific community is closely monitoring the replacement of antibiotics with doses of ZnO in weaned piglets. Since 2022, the use of zinc in medical doses has been banned in the European Union. Therefore, pig farmers are looking for other solutions. Some studies have suggested that zinc nanoparticles might replace ZnO for the prevention of diarrhea in weaning piglets. Like ZnO, zinc nanoparticles are effective against pathogenic microorganisms, e.g., Enterobacteriaceae family in vitro and in vivo. However, the effect on probiotic Lactobacillaceae appears to differ for ZnO and zinc nanoparticles. While ZnO increases their numbers, zinc nanoparticles act in the opposite way. These phenomena have been also confirmed by in vitro studies that reported a strong antimicrobial effect of zinc nanoparticles against Lactobacillales order. Contradictory evidence makes this topic still controversial, however. In addition, zinc nanoparticles vary in their morphology and properties based on the method of their synthesis. This makes it difficult to understand the effect of zinc nanoparticles on the intestinal microbiome. This review is aimed at clarifying many circumstances that may affect the action of nanoparticles on the weaning piglets' microbiome, including a comprehensive overview of the zinc nanoparticles in vitro effects on bacterial species occurring in the digestive tract of weaned piglets.

Growth Performance, Antioxidative Capacity, and Intestinal Histomorphology of Grey Mullet (Liza ramada)-Fed Dietary Zinc Nanoparticles

Zinc is one of the essential microelements involved in vital physiological and biological functions in the fish body. The study evaluated the growth performance, antioxidative capacity, and intestinal histomorphology of Grey Mullet (Liza ramada)-fed dietary zinc nanoparticles (ZnO-NPs) at 0, 10, 20, and 40 mg/kg for the first time. The final weight and specific growth rate (SGR) of Grey Mullet-fed dietary ZnO-NPs at 20 and 40 mg/kg were meaningfully enhanced (p < 0.05). Further, the weight gain (WG) was significantly higher in fish treated with ZnO-NPs than the control, and fish fed 20-40 mg/kg had the highest WG (p < 0.05). The feed conversion ratio (FCR) was meaningfully reduced in fish fed 20-40 mg ZnO-NPs/kg (p < 0.05). The histomorphology of the intestines revealed a significant improvement in villus height, villus width, and goblet cells by ZnO-NPs. The lysozyme activity, phagocytic activity, and phagocytic index showed higher levels in Grey Mullet-fed dietary ZnO-NPs at 20 mg/kg than fish fed 0, 10, and 40 mg/kg (p < 0.05). Superoxide dismutase (SOD) and catalase (CAT) were markedly improved in Grey Mullet treated with ZnO-NPs compared with the control, and the group of fish treated with 20 mg/kg had the highest SOD and CAT (p < 0.05). Glutathione peroxidase (GPx) was significantly higher in fish fed 20-40 mg/kg ZnO-NPs than fish fed 0-10 mg/kg and fish fed 40 mg ZnO-NPs/kg showing the highest GPx value (p < 0.05). The concentration of malondialdehyde was markedly lowered in Grey Mullet fed ZnO-NPs at varying levels (p < 0.05). Based on the overall results, the regression analysis suggests that ZnO-NPs can be included at 24.61-35.5 mg/kg for the best performances of Grey Mullet.

Impact of Dietary Zinc Chloride Hydroxide and Zinc Methionine on the Faecal Microbiota of Healthy Adult Horses and Ponies

Zinc supplements are often used in equine nutrition to support skin and hoof quality or the immune function. However, no data on the effects of dietary zinc on the intestinal microbiota of horses and ponies are available so far. In the present study, varying dietary zinc concentrations (maintenance (4 mg/kg BW^0.75/day), 120 mg/kg dry matter (DM)/day and 240 mg/kg DM/day) were achieved by the supplementation of either zinc chloride hydroxide or zinc methionine (six treatment periods of 4 weeks each). Eight healthy adult ponies and two healthy adult horses were included, and faecal samples were collected at the end of each treatment period to analyse the microbiota (16S rDNA sequencing) and microbial metabolites. With increasing dietary zinc concentrations, the richness of the faecal microbiota decreased, independently of the zinc compound used. In addition, a decrease of the relative abundance of Bacteroidetes and Fibrobacteres as well as of acetate and total short-chain fatty acids in the faeces of the animals was observed at high zinc intakes. Effects on the bacterial order, family and genus level were also detected, which were partly more pronounced for zinc chloride hydroxide. It can be concluded that high dietary zinc levels decrease the richness and fermentative activity of the faecal microbiota of horses and ponies. Although all animals were healthy throughout the study, the effects could be critical for gut health, and deserve more research. The detected differences between the zinc compounds used indicate differences in the bioavailability of organic and inorganic zinc sources in equines.