Comparative effects of nano elemental selenium and sodium selenite on selenium retention in broiler chickens

Exploring the effects of varying levels of selenium-chitosan on production performance, egg quality, and immune health in laying japanese quail

The purpose of this research was to see how different levels of Se-chitosan, a novel organic source of Se, affected the production performance, egg quality, egg Se concentration, microbial population, immunological response, antioxidant status, and yolk fatty acid profile of laying Japanese quail. This experiment used a totally randomized design, with 5 treatments, 6 repeats, and 10 birds in each repetition. The dietary treatment groups were as follows: no Se supplementation (control group), 0.2 mg/kg Na-selenite supplementation, and 0.2, 0.4, and 0.6 mg/kg Se-chitosan supplementation. The feed conversion ratio (FCR) improved linearly in quails fed different levels of Se-chitosan compared to the control group (P < 0.05). Furthermore, Se-chitosan at concentrations of 0.2 and 0.4 mg/kg demonstrated both linear and quadratic increases in albumen height, Haugh unit, and yolk color in fresh eggs compared to the control group. Additionally, Se-chitosan contributed to enhanced shell thickness and strength, along with an increased Se concentration in the yolk. Se-chitosan supplementation at different levels linearly and quadratically reduced coliforms (COL) while increasing lactic acid bacteria (LAB)/coliform ratios (P < 0.05). Se-chitosan supplementation linearly and quadratically increased the total antibody response to sheep red blood cells (SRBC) and IgG titers (P < 0.05). It also linearly decreased the level of malondialdehyde in fresh and stored egg yolks and increased the activity of antioxidant enzymes catalase and glutathione peroxidase linearly, and superoxide dismutase (SOD) both linearly and quadratically in quail blood serum (P < 0.05). Additionally, supplementation of Se-chitosan at levels of 0.2 and 0.6 mg/kg linearly decreased the ∑ n-6 PUFA/∑ n-3 PUFA ratio in the yolk compared to the control group (P < 0.05). It can be concluded that incorporating Se-chitosan as a novel organic source of Se in the diet of laying quails can enhance production performance, egg quality, egg Se concentration, yolk lipid oxidation, microbial population, immune response, antioxidant enzyme activity, and yolk fatty acid profile.

Effect of Dietary Supplementation of Organic Selenium Nanoparticles on Growth Performance and Carcass Traits of Broiler Chickens

This study examined how broilers up to 38 days of age fared regarding growth efficiency and carcass characteristics concerning selenium nanoparticle activities (SeNPs). A total of 180 one-week-old broiler (Cobb 500) chicks without sex were randomly allocated into three groups, each with six replications of 10 chicks. The trial took 38 days to complete. The three study dietary groups were fed ad libitum feed and water throughout their 38-day of age, along with corn-and-soybean meal-based diets supplemented with 0 (control), 1.5, and 2.0 ml SeNPs (concentration = 5%) /kg diet, respectively. According to the current findings, the SeNP supplementation groups had greater body weight, weight gain, and performance indicators than the control group after 38 days of the feeding experiment. The findings demonstrated that dietary interventions did not affect the amount of feed consumed (FC) per chick per day or the feed conversion ratio (FCR). The conclusion is that adding SeNPs to broiler diets at 1.5 or 2.0 ml/kg increased productivity. In contrast, lower levels of selenium (Se) (1.5 ml/kg diet) showed encouraging results and could be employed as a useful feed additive in broilers.

Effects of replacing Na selenite in laying hen feed with selenized glucose on production performance, egg quality, egg selenium content, microbial population, immunological response, antioxidant enzymes, and fatty acid composition

This study aimed to explore the effects of selenized glucose (SeGlu) and Na selenite supplementation on various aspects of laying hens such as production performance, egg quality, egg Se concentration, microbial population, antioxidant enzymes activity, immunological response, and yolk fatty acid profile. Using a 2 × 2 factorial design, 168 laying hens at 27-wk of age were randomly divided into 4 treatment groups with 7 replications. Se source (Na selenite and SeGlu) and Se level (0.3 and 0.6 mg/kg) were used as treatments. When 0.3 mg SeGlu/kg was compared to 0.3 mg Na selenite/kg, the interaction findings revealed that 0.3 mg SeGlu/kg increased egg production percent and shell ash (P < 0.05). When compared to 0.3 mg Na selenite/kg, dietary supplementation with 0.3 and 0.6 mg SeGlu/kg resulted in an increase in albumen height, Haugh unit, and yolk color of fresh eggs (P < 0.05). SeGlu enhanced albumen height, Haugh unit, shell thickness (P < 0.01), albumen index, yolk share, specific gravity, shell ash (P < 0.05) of fresh eggs and shell thickness (P < 0.05) of stored eggs as compared to Na selenite. The interaction showed that 0.6 mg SeGlu/kg enhanced yolk Se concentration while decreasing malondialdehyde levels in fresh egg yolk (P < 0.05). SeGlu enhanced Se concentration in albumen and glutathione peroxidase activity in plasma (P < 0.05) as compared to Na selenite. 0.6 mg Se/kg increased lactic acid bacteria, antibody response to sheep red blood cells, and lowered ∑n-6 PUFA/ ∑n-3 PUFA ratio (P < 0.05). As a result, adding SeGlu to the feed of laying hens enhanced egg production, egg quality, egg Se concentration, fresh yolk lipid oxidation, and glutathione peroxidase enzyme activity.

Impact of different forms of selenium supplementation on growth and physiological performance of New Zealand white rabbits

Forty-eight weaned male New Zealand White rabbits aged 6 weeks with an initial body weight of (709.67 ± 13 g) were randomly divided into six experimental groups (8 rabbits each) for 6-14 weeks of age experimental periods. The present study was planned to evaluate the effect of using different forms of Selenium element (inorganic, nanoparticles and organic) as dietary supplementation on productive performance of rabbits. Six experimental groups in completely randomized design were used. The first group (G1, control) was fed the basal diet to cover maintenance and production allowances. Rabbits in the other groups G2, G3, G4 and G5 were fed the basal diet supplemented with Nano- Se at 0.02, 0.03, 0.04 and 0.05 mg/kg diet, respectively. The 6th group (G6) was fed the basal diet supplemented with 0.1 mg/kg diet of salinized yeast (Se-yeast) as organic form. The results indicated that the highest values of nitrogen free extract (NFE) and crude fiber (CF) digestibility, live body weight, daily weight gain, hot carcass weight and dressing percentage were observed with those supplemented with Nano-Se at all levels compared with other treatments. However, feed conversion, net revenue and economic efficiency values were improved with Nano-Se groups followed by organic Se group in comparisons with the control group. Conclusively, the Nano-Se in rabbit's diet has a positive effect in improving rabbit's performance and economic efficiency compared to the inorganic Selenium.

Nanoselenium attenuates renal ischemia-reperfusion injury in rats

Using selenium (Se) nanoparticles has received attention in recent years because of their therapeutic benefits due to their anticancer, antioxidant, anti-inflammatory, and anti-diabetic effects. This research was conducted to evaluate the possible protective impact of nano-Se on renal unilateral ischemia/reperfusion injury (uIRI) in adult male Wistar rats. Using clamping of the left renal pedicle within 45 min uIRI was induced. The animals were randomly divided into nine groups of control, nano-Se (0.25, 0.5, and 1 mg/kg bw/day) alone, uIRI control, and uIRI rats administrated with nano-Se. At 30 days after treatment, the animals were sacrificed to be assessed biochemically and histopathologically. Nano-Se in uIRI groups have significantly decreased serum creatinine, urea levels, renal histological damage, and increased antioxidant status. Also, our findings demonstrated that the administration of nano-Se caused a significant decrease in the immunoreactivity level of the epidermal growth factor (EGF) and EGFR expression (EGF receptor) in the renal tissue of the uIRI rats. Therefore, nano-Se possesses renoprotective effects, and this effect might be attributable to its antioxidant and free radical scavenger effects. These renoprotective effects may depend on the decreased EGF immunoreactivity level and EGFR expression in the kidney tissue and improve the structure of the kidney tissue. Thus, our research provided biochemical and histological data supporting the potential clinical use of nano-Se for the treatment of certain kidney disorders.

A Meta-analysis of Optimum Level of Dietary Nanoselenium on Performances, Blood Constituents, Antioxidant Activity, Carcass, and Giblet Weight of Broiler Chickens

Contradictory reports regarding the effects of nanoselenium (NanoSe) on the performance of broiler chickens may occur. Therefore, the optimum supplementation of NanoSe doses needs to be determined. The current meta-analysis study was aimed at evaluating the effectiveness and the optimum doses of NanoSe supplementation in broiler diets on performance, blood constituents, carcass, and giblet weight by considering breed and sex. The database was obtained from online scientific publications by searching through search engines such as Scopus, Web of Science, Google Scholar, and PubMed by entering the keywords nanoselenium, performance, antioxidants, and broiler. A total of 25 articles were included in the meta-analysis database. The study group was treated as a random effect while NanoSe dose, breed, and sex were treated as fixed effects. Daily body weight gain, carcass weight, and breast weight increased quadratically (P < 0.05), and FCR decreased quadratically (P < 0.05) in the starter and cumulative periods with increasing NanoSe supplementation. NanoSe supplementation tended to decrease cumulative feed intake linearly (P < 0.1) and decreased (P < 0.05) abdominal fat, albumin, red blood cells, ALT, and MDA levels. In contrast, levels of total protein, globulin, glucose, AST, white blood cells, cholesterol, triglyceride, and the weight of the liver, heart, gizzard, bursa of Fabricius, thymus, and spleen were not affected by NanoSe supplementation. Increasing the dose of NanoSe increased (P < 0.05) the GSHPx enzyme and Se concentration in breast muscle and liver and tended to enhance (P < 0.01) the CAT enzyme. It is concluded that a proper dose of NanoSe supplementation in a broiler diet improves body weight gain, feed efficiency, carcass, and breast weight without adverse effects on giblets. Dietary NanoSe elevates Se concentration in the breast muscle and liver and antioxidant activity. The current meta-analysis shows that the optimum dose for body weight gain and FCR is 1 to 1.5 mg/kg.

miR-20a-5p targeting mfn2-mediated mitochondria-lipid droplet contacts regulated differential changes in hepatic lipid metabolism induced by two Mn sources in yellow catfish

Understanding the hazards of different forms of metal elements provided innovative insights into their toxicity and environmental risk assessment. To date, few studies had been conducted to investigate the differential effects and mechanisms of MnO2 NPs and MnSO4, two widely distributed environmental pollutants, on hepatic toxicity and lipid metabolism since lipid metabolism-relevant parameters were broadly used as biomarkers for risk assessment of hazardous contaminants. Thus, using yellow catfish Pelteobagrus fulvidraco, an ecologically and economically important freshwater fish as the model, the present study investigated the differential effects and mechanisms of MnO2 NPs and MnSO4 influencing hepatic lipid metabolism. Compared to MnSO4, MnO2 NPs increased hepatic Mn content, induced lipotoxicity, up-regulated the mRNA expression of lipogenic genes, increased peridroplet mitochondrial (PDM) contents, intensified the contact between mitochondria and lipid droplets (LDs), and downregulated miR-20a-5p abundance. Importantly, miR-20a-5p targeted mfn2, which mediated the contact between mitochondria and LDs and influenced changes in lipid metabolism induced by MnO2 NPs. Mechanistically, the direct Mfn2-Plin2 binding and Mfn2 GTPase activity promoted the MnO2 NPs-induced interactions between mitochondria and LDs, which in turn influenced MnO2 NPs-induced changes in hepatic lipid metabolism. For the first time, our findings indicated the significant differences between the changes in body metabolism induced by nanoparticles and inorganic elements, which helped to illuminate different mechanisms governing the responses of aquatic vertebrates to hazardous metal pollutants (MnO2 NPs and MnSO4).

The effect of replacing sodium selenite with selenium-chitosan in laying hens on production performance, egg quality, egg selenium concentration, microbial population, immunological response, antioxidant enzymes, and fatty acid composition

The purpose of this study was to investigate into the effects of Se-chitosan and Na selenite supplementation on laying hen production performance, egg quality, egg Se concentration, microbial population, immunological response, antioxidant enzymes activity, and yolk fatty acid profile. Using a 2 × 2 factorial design, 168 27-wk-old laying hens were randomly divided into 4 treatment groups and 7 replications. Se source (Na selenite and Se-chitosan) and Se level (0.3 and 0.6 mg/kg) were used as treatments. Se-chitosan enhanced egg production percentage and egg mass (P < 0.05) when compared with Na selenite. There was an interaction, with 0.6 mg Se-chitosan/kg causing an increase in albumen height, Haugh unit, albumen index, and shell thickness of fresh eggs (P < 0.05). Se-chitosan increased yolk share, yolk color, and shape index of fresh eggs and shape index, albumen index, albumen height, Haugh unit, yolk color, shell thickness, and specific gravity of stored eggs (P < 0.05). The interaction showed that, 0.6 mg Se-chitosan/kg increased albumen Se concentration and decreased the level of malondialdehyde (MDA) in fresh egg yolk compared with 0.3 and 0.6 mg Na selenite/kg (P < 0.05). When compared with Na selenite, Se-chitosan increased the Se concentration in the yolk and decreased level of MDA in stored egg yolk (P < 0.01). When compared with Na selenite, Se-chitosan reduced coliforms (P < 0.01), increased lactic acid bacteria, and the lactic acid bacteria/coliform ratio (P < 0.05). Se-chitosan supplementation increased antibody response to sheep red blood cells and IgM titers and the activities of glutathione peroxidase and superoxide dismutase in plasma (P < 0.05). Furthermore, compared with Na selenite, supplementing diets with Se-chitosan decreased ∑ n-6 PUFA/∑ n-3 PUFA ratio (P < 0.01). In conclusion, Se-chitosan supplementation of laying hen feed improved production performance, egg quality, egg Se concentration, yolk lipid oxidation, microbial population, immune response, antioxidant enzymes activity, and yolk fatty acid profile, with 0.6 mg Se-chitosan/kg supplementation being optimal.

Advances in selenium supplementation: From selenium-enriched yeast to potential selenium-enriched insects, and selenium nanoparticles

Selenium (Se) is an essential micronutrient that plays an important role in animal and human development and physiological homoeostasis. This review surveys the role of Se in the environment, plants and animal bodies, and discusses data on Se biofortification with different sources of supplementation, from inorganic to organic forms, with special focus on Se-enriched yeast (Se-yeast). Although Se-yeast remains one of the main sources of organic Se, other emerging and innovative sources are reviewed, such as Se-enriched insects and Se-nanoparticles and their potential use in animal nutrition. Se-enriched insects are discussed as an option for supplying Se in organic form to livestock diets. Se-nanoparticles are also discussed, as they represent a more biocompatible and less toxic source of inorganic Se for animal organisms, compared to selenite and selenate. We also provide up to date information on the legal framework in the EU, USA, and Canada of Se that is contained in feed additives. From the scientific evidence available in the literature, it can be concluded that among the inorganic forms, sodium selenite is still one of the main options, whereas Se-yeast remains the primary organic form. However, other potential sources such as Se-enriched insects and Se-nanoparticles are being investigated as they could potentially combine a high bioavailability and reduced Se emissions in the environment.

Nano-Sized Selenium Maintains Performance and Improves Health Status and Antioxidant Potential While Not Compromising Ultrastructure of Breast Muscle and Liver in Chickens

The poultry industry is looking for the most effective sources of selenium (Se) for commercial use. Over the past five years, nano-Se has attracted a great deal of attention in terms of its production, characterisation and possible application in poultry production. The objective of this study was to evaluate the effects of dietary levels of inorganic and organic Se, selenised yeast and nano forms of selenium on breast meat quality, liver and blood markers of antioxidants, the ultrastructure of tissue and the health status of chickens. A total of 300 one-day-old chicks Ross 308 were divided into 4 experimental groups, in 5 replications, with 15 birds per replication. Birds were fed the following treatments: a standard commercial diet containing inorganic Se in the form of inorganic Se at the level of 0.3 mg/kg diet and an experimental diet with an increased level of Se (0.5 mg/kg diet). The use of other forms of Se (nano-Se) versus sodium selenate significantly influences (p ≤ 0.05) a higher collagen content and does not impair physico-chemical properties in the breast muscle or the growth performance of the chickens. In addition, the use of other forms of selenium at an increased dose versus sodium selenate affected (p ≤ 0.01) the elongation of sarcomeres in the pectoral muscle while reducing (p ≤ 0.01) mitochondrial damage in hepatocytes and improving (p ≤ 0.05) oxidative indices. The use of nano-Se at a dose of 0.5 mg/kg feed has high bioavailability and low toxicity without negatively affecting the growth performance and while improving breast muscle quality parameters and the health status of the chickens.

Physiological Benefits of Novel Selenium Delivery via Nanoparticles

Dietary selenium (Se) intake within the physiological range is critical to maintain various biological functions, including antioxidant defence, redox homeostasis, growth, reproduction, immunity, and thyroid hormone production. Chemical forms of dietary Se are diverse, including organic Se (selenomethionine, selenocysteine, and selenium-methyl-selenocysteine) and inorganic Se (selenate and selenite). Previous studies have largely investigated and compared the health impacts of dietary Se on agricultural stock and humans, where dietary Se has shown various benefits, including enhanced growth performance, immune functions, and nutritional quality of meats, with reduced oxidative stress and inflammation, and finally enhanced thyroid health and fertility in humans. The emergence of nanoparticles presents a novel and innovative technology. Notably, Se in the form of nanoparticles (SeNPs) has lower toxicity, higher bioavailability, lower excretion in animals, and is linked to more powerful and superior biological activities (at a comparable Se dose) than traditional chemical forms of dietary Se. As a result, the development of tailored SeNPs for their use in intensive agriculture and as candidate for therapeutic drugs for human pathologies is now being actively explored. This review highlights the biological impacts of SeNPs on growth and reproductive performances, their role in modulating heat and oxidative stress and inflammation and the varying modes of synthesis of SeNPs.

Biogenic Selenium Nanoparticles in Biomedical Sciences: Properties, Current Trends, Novel Opportunities and Emerging Challenges in Theranostic Nanomedicine

Selenium is an important dietary supplement and an essential trace element incorporated into selenoproteins with growth-modulating properties and cytotoxic mechanisms of action. However, different compounds of selenium usually possess a narrow nutritional or therapeutic window with a low degree of absorption and delicate safety margins, depending on the dose and the chemical form in which they are provided to the organism. Hence, selenium nanoparticles (SeNPs) are emerging as a novel therapeutic and diagnostic platform with decreased toxicity and the capacity to enhance the biological properties of Se-based compounds. Consistent with the exciting possibilities offered by nanotechnology in the diagnosis, treatment, and prevention of diseases, SeNPs are useful tools in current biomedical research with exceptional benefits as potential therapeutics, with enhanced bioavailability, improved targeting, and effectiveness against oxidative stress and inflammation-mediated disorders. In view of the need for developing eco-friendly, inexpensive, simple, and high-throughput biomedical agents that can also ally with theranostic purposes and exhibit negligible side effects, biogenic SeNPs are receiving special attention. The present manuscript aims to be a reference in its kind by providing the readership with a thorough and comprehensive review that emphasizes the current, yet expanding, possibilities offered by biogenic SeNPs in the biomedical field and the promise they hold among selenium-derived products to, eventually, elicit future developments. First, the present review recalls the physiological importance of selenium as an oligo-element and introduces the unique biological, physicochemical, optoelectronic, and catalytic properties of Se nanomaterials. Then, it addresses the significance of nanosizing on pharmacological activity (pharmacokinetics and pharmacodynamics) and cellular interactions of SeNPs. Importantly, it discusses in detail the role of biosynthesized SeNPs as innovative theranostic agents for personalized nanomedicine-based therapies. Finally, this review explores the role of biogenic SeNPs in the ongoing context of the SARS-CoV-2 pandemic and presents key prospects in translational nanomedicine.

Bioactive-loaded nanodelivery systems for the feed and drugs of livestock; purposes, techniques and applications

Advances in animal husbandry and better performance of livestock results in growing demands for feed and its nutrients, bioactive compounds (bioactives), such as vitamins, minerals, proteins, and phenolics, along with drugs/vaccines. To protect the feed bioactives in unintended circumstances, they can be encapsulated to achieve desired efficacy in animal feeding and nanoencapsulation gives more potential for better protection, absorption and targeted delivery of bioactives. This study reviews structures, properties, and methods of nanoencapsulation for animal feedings and relevant drugs. Essential oil (EOs) and plant extracts are mostly encapsulated bioactives and phytochemicals for poultry diets and chitosan is found as most effective nanocarrier to load EOs and plant extracts. Nanoparticles (NPs) and nanocapsules are frequently studied nanocarriers, which are mostly processed by using the ionotropic/ionic gelation. Nanofibers, nanohydrogels and nanoemulsions are not found yet for their application in feed bioactives. These nanocarriers can have an improved protection, stability, and controlled release of feed bioactives which benefits to additional nutrition for the growth of livestock regardless of the low stability and water solubility of bioactives. For ruminants' feeds, nano-minerals, vitamins, phytochemicals, essential fatty acids, and drugs are encapsulated by NPs to facilitate the delivery to target organs through direct penetration, to improve their bioavailability, to generate more efficient absorption in cells and tissues, and protect them from rapid degradation. Furthermore, safety and regulatory issues, as well as advantages and disadvantages of nanoencapsulation application in animal feeds are also discussed. The review shows an accurate design of NPs can largely mask safety issues with straightforward approaches and awareness of safety concerns is fundamental for better designing of nanoencapsulation systems and commercialization. This review gives an insight of understanding and potential of nanoencapsulation in ruminants and poultry feedings to obtain a better bioavailability of the nutrients and bioactives with improved safety and awareness for better designing of nanoencapsulating systems.

Biogenic Selenium Nanoparticles and Their Anticancer Effects Pertaining to Probiotic Bacteria—A Review

Selenium nanoparticles (SeNPs) can be produced by biogenic, physical, and chemical processes. The physical and chemical processes have hazardous effects. However, biogenic synthesis (by microorganisms) is an eco-friendly and economical technique that is non-toxic to human and animal health. The mechanism for biogenic SeNPs from microorganisms is still not well understood. Over the past two decades, extensive research has been conducted on the nutritional and therapeutic applications of biogenic SeNPs. The research revealed that biogenic SeNPs are considered novel competitors in the pharmaceutical and food industries, as they have been shown to be virtually non-toxic when used in medical practice and as dietary supplements and release only trace amounts of Se ions when ingested. Various pathogenic and probiotic/nonpathogenic bacteria are used for the biogenic synthesis of SeNPs. However, in the case of biosynthesis by pathogenic bacteria, extraction and purification techniques are required for further useful applications of these biogenic SeNPs. This review focuses on the applications of SeNPs (derived from probiotic/nonpathogenic organisms) as promising anticancer agents. This review describes that SeNPs derived from probiotic/nonpathogenic organisms are considered safe for human consumption. These biogenic SeNPs reduce oxidative stress in the human body and have also been shown to be effective against breast, prostate, lung, liver, and colon cancers. This review provides helpful information on the safe use of biogenic SeNPs and their economic importance for dietary and therapeutic purposes, especially as anticancer agents.

Comprehensive Approaches of Nanoparticles for Growth Performance and Health Benefits in Poultry: An Update on the Current Scenario

Currently, providing nutritious food to all people is one of the greatest challenges due to rapid human population growth. The global poultry industry is a part of the agrifood sector playing an essential role in food insecurity by providing nutritious meat and egg sources. However, limited meat production with less nutritional value is not fulfilling the higher market demands worldwide. Researchers are focusing on nanobiotechnology by employing phytosynthesized mineral nanomaterials to improve the growth performance and nutritional status of broilers as these mineral nanoparticles are usually absorbed in greater amounts from the gastrointestinal tract and exert enhanced biological effects in the target tissues of animals with greater tissue accumulation. These mineral nanoparticles are efficiently absorbed through the gastrointestinal tract and reach essential organs via blood. As a result, it enhances growth performance and nutritional value with less toxicity and tremendous bioavailability properties. In this review, the research work conducted in the recent past, on the different aspects of nanotechnology including supplementation of mineral nanoparticle in diet and their potential role in the poultry industry, has been concisely discussed.

Toxicological effects of nanoselenium in animals

The productivity and sustainability of livestock production systems are heavily influenced by animal nutrition. To maintain homeostatic balance in the body of the animal at different phases of life, the percentage of organically active minerals in livestock feed must be optimized. Selenium (Se) is a crucial trace mineral that is required for the maintenance of many functions of the body. Se nanoparticles (SeNPs) attracted considerable interest from researchers for a variety of applications a decade ago, owing to their extraordinary properties. SeNPs offer significant advantages over larger-sized materials, by having a comparatively wider surface area, increased surface energy, and high volume. Despite its benefits, SeNP also has toxic effects, therefore safety concerns must be taken for a successful application. The toxicological effects of SeNPs in animals are characterized by weight loss, and increased mortality rate. A safe-by-strategy to certify animal, human and environmental safety will contribute to an early diagnosis of all risks associated with SeNPs. This review is aimed at describing the beneficial uses and potential toxicity of SeNPs in various animals. It will also serve as a summary of different levels of SeNPs which should be added in the feed of animals for better performance.

Comparing the Influences of Selenium Nanospheres, Sodium Selenite, and Biological Selenium on the Growth Performance, Blood Biochemistry, and Antioxidative Capacity of Growing Turkey Pullets

Supplementation of selenium in poultry feed is required in an optimum dose and form for optimizing the growth performance and health status. Selenium nanospheres are suggested as an efficient and alternative to the conventional organic or inorganic forms. The study evaluated the effects of selenium (Se) nanospheres (SeNPs) as an alternative to organic Se (Sel-Plex^®) or inorganic Se (sodium selenite, Se(IV Se(IV)) on the growth performance, carcass traits, blood biochemistry, and antioxidative capacity in turkey pullets. A total of 160 1-day-old Bronze turkey poults chicks were divided into four groups with 40 pullets each. The birds were fed on four types of diets as fellow: control (basal diet, 0.01 Se mg/kg), SeNPs (0.43 Se mg/kg), organic Se Sel-Plex^® (0.41 Se mg/kg), and inorganic Se(IV) (0.42 Se mg/kg) for 8 weeks. No changes were seen in the body weight gain in growing turkey pullet, but chicks fed with Sel-Plex^® form recorded the lowest feed intake (p < 0.05) compared to other treatments. Dietary SeNPs and Se(IV) selenium sources improved the feed conversion ratio compared to other treatments. All Se forms fed on turkey pullets showed higher carcass percentage weight and liver Se content than the control group. However, the gizzard percentage weight in the SeNPs group was lower than in the other treatments (p < 0.05). Birds fed SeNPs, and Sel-Plex^® forms supplemental diets had a lower cholesterol concentration (p < 0.05) than the control and Se(IV). While high-density lipoprotein (HDL) concentration was increased in SeNPs and Se(IV) groups, and total protein concentration was higher in the Se(IV) group. Furthermore, dietary SeNPs reduced (p < 0.05) the low-density lipoprotein (LDL), total lipids, triglycerides, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine, uric acid, urea, and malondialdehyde plasma concentrations and increased the glutathione peroxidase activity (GPx) and total antioxidative capacity (TAC). In conclusion, the results confirmed that feeding turkey pullets on SeNPs form with the 0.4 Se mg/kg of feed enhanced feed efficiency, growth performance, carcass traits, plasma lipids concentration, and antioxidative capacity.

Selenium nanoparticles enhance the efficacy of homologous vaccine against the highly pathogenic avian influenza H5N1 virus in chickens

A proper vaccination against avian influenza viruses in chicken can significantly reduce the risk of human infection. Egypt has the highest number of recorded humans highly pathogenic avian influenza (HPAI)-H5N1 infections worldwide despite the widespread use of homologous vaccines in poultry. Enhancing H5N1 vaccine efficacy is ultimately required to better control HPAI-H5N1. The aim of this study is to boost chicken immunity by combined with inactivated HPAI-H5N1 with selenium nanoparticles (SeNPs). The chickens groups 1-3 were fed diets supplemented with SeNPs concentrations (0.25, 0.5, and 1 mg/kg) for 3 weeks and then vaccinated (inactivated HPAI-H5N1). while groups 4,5 and 6 were fed with SeNPs free diets and administered with 0.5 ml of the vaccine combined with 0.02, 0.06, and 0.1 mg/dose of SeNPs and then all groups were challenged with homologous virus 3 weeks post-vaccination (WPV). Group 7, 8 were used as control positive and negative respectively. At 4, 5, and 6 WPV, antibody titer was considerably higher in the group fed a meal supplemented with 1 mg SeNPs/kg. In contrast, both methods of SeNPs supplementation significantly increased the Interleukin 2 (IL2), Interleukin 6 (IL6), and Interferon γ (IFNγ) expressions in the blood cells in a dose-dependent manner, with a higher expression observed in the group that was vaccinated with 0.1 mg/dose. After the challenge, all groups that received SeNPs via diet or vaccines dose showed significant reduction in viral shedding and milder inflammation in lung, trachea, spleen, and liver in addition to higher expression of IL2, IL6, and IFNγ, with the highest expression observed in the group that was vaccinated with 0.1 mg/dose compared the plain vaccinated group. The groups of 1 mg SeNPs/kg and combined vaccinated with 0.1 mg/dose showed the best vaccine efficacy. However, the group vaccinated with 0.1 mg/dose showed the earliest reduction in viral shedding. Overall, SeNPs supplementation in the diet and the administration of the vaccine formula with SeNPs could enhance vaccine efficacy and provide better protection against HPAI-H5N1 in chickens by enhancing cellular immunity and reducing inflammation. We recommend using SeNPs as a vaccine combination or feeding with diet to increase the immunity and vaccine efficacy against H5N1.

Improving selenium accumulation in broilers using Escherichia coli Nissle 1917 with surface-displayed selenite reductase SerV01

Selenium levels have a critical impact on livestock and poultry, and selenium nanoparticles (SeNPs) have shown significant efficiency in supplementation. This study identified a high-efficiency selenite reductase, SerV01, in Staphylococcus aureus LZ-01, which can convert Se₂O₃^2- to SeNPs. Subsequently, SerV01 was introduced into the intestines of the broilers using the surface display-engineered E. coli Nissle 1917 (EcN). The results showed that the engineered bacteria (EcN-IS) significantly increased the selenium content by 0.87 mg kg^-1, 0.52 mg kg^-1, and 6.10 mg L^-1 in the liver, breast muscle, and serum, respectively. With SeNPs + EcN-IS treatment, glutathione peroxidase and thioredoxin reductase levels reached 0.7536 ± 0.03176 U μL^-1 protein and 2.463 ± 0.1685 U μL^-1 protein, respectively. With the modified probiotics, the proportion of beneficial intestinal flora increased, with Lactobacillus and Propionibacterium accounting for 75.85% and 0.19%. This technology provides a novel idea to facilitate the exploitation of selenium in broiler diets and improve antioxidant capability.

Poly-L-Lysine-Lactobionic Acid-Capped Selenium Nanoparticles for Liver-Targeted Gene Delivery

Liver cancer is currently regarded as the second leading cause of cancer-related mortality globally and is the sixth most diagnosed malignancy. Selenium nanoparticles (SeNPs) have attracted favorable attention as nanocarriers for gene therapy, as they possess beneficial antioxidant and anticancer properties. This study aimed to design, functionalize and characterize SeNPs to efficiently bind, protect and deliver pCMV-Luc DNA to hepatocellular carcinoma (HepG2) cells. The SeNPs were synthesized by ascorbic acid reduction and functionalized with poly-L-lysine (PLL) to stabilize and confer positive charges to the nanoparticles. The SeNPs were further decorated with lactobionic acid (LA) to target the asialoglycoprotein receptors abundantly expressed on the surface of the hepatocytes. All SeNPs were spherical, in the nanoscale range (<130 nm) and were capable of successfully binding, compacting and protecting the pDNA against nuclease degradation. The functionalized SeNP nanocomplexes exhibited minimal cytotoxicity (<30%) with enhanced transfection efficiency in the cell lines tested. Furthermore, the targeted SeNP (LA-PLL-SeNP) nanocomplex showed significant (* p < 0.05, ** p < 0.01, **** p < 0.0001) transgene expression in the HepG2 cells compared to the receptor-negative embryonic kidney (HEK293) cells, confirming receptor-mediated endocytosis. Overall, these functionalized SeNPs exhibit favorable features of suitable gene nanocarriers for the treatment of liver cancer.

Protective effects of different concentrations of selenium nanoparticles on rainbow trout (Oncorhynchus mykiss) primary hepatocytes under heat stress

Heat stress leads to altered expression of associated heat shock proteins (HSPs), which are critical molecular chaperones related to cellular function in living organisms. Selenium nanoparticles (SeNPs), a nanocomposite form of Se, have a protective effect against heat stress-induced cellular damage. In this study, primary rainbow trout hepatocytes were isolated to identify the protective function of SeNPs in rainbow trout hepatocytes. Experiments were divided into five groups and SeNPs were added at concentrations of 0, 2.0, 3.0, 5.0 and 8.0 μg/mL and incubated at 18 ℃ for 4, 8, 12, 24 and 48 h respectively. Hepatocyte viability, GSH-Px and SOD activity were enhanced and MDA content was reduced following the addition of SeNPs. Expression of GSH-P1 and genes related to HSPs (including HSP70a, HSP60, HSP90β, HSP10 and HSP47) were significantly increased and the optimal concentration of SeNPs for adding to hepatocytes was identified as 5.0 µg/mL. Adding 5.0 µg/mL SeNPs following heat stress (24 ℃) increased hepatocyte viability, GSH-Px and SOD activity, while MDA levels first decreased and then increased. Expression of GSH-P1 and genes related to HSPs (including HSP70a, HSP60, HSP90β, HSP10 and HSP47) were significantly higher than controls. In summary, SeNPs and slight heat stress synergistically enhanced the expression of GSH-P1 and HSPs and protected hepatocytes from heat stress damage, suggesting that SeNPs is a potential hepatocyte protective therapeutic agent.

Prospects and future perspectives of selenium nanoparticles: An insight of growth promoter, antioxidant and anti-bacterial potentials in productivity of poultry

Nanoparticles have been attracted attention in poultry research due to their low toxicity, higher bio-availability, high surface area with sustained drug release. Dietary supplementation with selenium nanoparticles (Se-NPs) plays a regulatory role in maintaining growth performance, feed conversion ratio (FCR), antioxidant defense as well as microbial control. Se-NPs have emerging importance in modulating intestinal health through the maintenance of beneficial microbes (microflora) as well as the production of short-chain fatty acids (SCFA). Se-NPs regulate intrinsic redox status by scavenging free radicals. The antioxidant potentiality of Se-NPs is influenced by the activation of the seleno-enzymes such as thioredoxin reductase and glutathione peroxidase family (GPx) involved in scavenging of Reactive Oxygen Species (ROS). The emerging significance of Se-NPs on antimicrobial activity has been exploited due to their bio-accumulative effects and biocompatibility potentiality in the cellular systems against poultry pathogens. The present review highlights on growth performance, antioxidant defense, and anti-bacterial potentiality of Se-NPs in poultry and also provide insight into its significance in the poultry industry.

Nano-selenium alleviating the lipid metabolism disorder of LMH cells induced by potassium dichromate via down-regulating ACACA and FASN

Chromium (Cr) VI is a common environmental contaminant highly toxic to livers. To explore the protective effect of nano-selenium (NANO-Se) on broiler liver damage caused by Cr (VI), this experiment was conducted with chicken hepatocellular carcinoma cell line (LMH) as the research object, using potassium dichromate (PDC) and NANO-Se gel for culturing cells. The results indicated that: (1) in the PDC-exposure group, LMH cells being treated with 20 μmol/L PDC for 24 h, IC50 (median inhibition concentration) = 23.427 could significantly reduce cell activity (p < 0.01) which decreased over time. PDC markedly increased the concentration of triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) in LMH cells (p < 0.01), which increased over time. In addition, PDC could substantially augment the transcription and protein levels of acetyl-CoA carboxylases alpha (ACACA) and fatty acid synthase (FASN) in LMH cells (p < 0.01). (2) Compared with the PDC-exposure group, the addition of 8 μmol/L NANO-Se after 12 h of PDC treatment could significantly increase the cell viability (p < 0.01) but decreased over time; the levels of TG and LDL-C in LMH cells declined markedly (p < 0.01). In addition, the transcription and protein levels of ACACA and FASN in LMH cells were significantly reduced (p < 0.01). (3) The LMH cells were cultured in advance with 8 μmol/L NANO-Se for 12 h and then with PDC for 24 h. The obtained results were similar to the above. There were no obvious differences in TG and LDL-C levels (p > 0.05). However, significant differences were found in the activity of LMH cells and the expression of genes related to lipid metabolism (p < 0.05).All these results suggest that the exposure to PDC promotes the increase of lipid synthesis in LMH cells and causes disorders in the lipid metabolism. Moreover, NANO-Se can partially attenuate the damage caused by PDC through down-regulating of the lipid metabolism-related genes (ACACA and FASN) in LMH cells.

Comparative analysis of various sources of selenium on the growth performance and antioxidant status in broilers under heat stress

The supplementation of Selenium-enriched probiotics is effective in reducing oxidative stress and maintaining meat quality stability in broiler chicken especially under heat stress. An experimental study was conducted to perform Comparative analysis of Selenium yeast with inorganic Se in broilers under heat stress. A total of 120 broilers chicks of one day were assigned to 4 groups each consisting 30 chicks fed on same basal diet but different selenium sources. The basal diet of group D1 was not supplemented with Se source (Negative control), group D2 basal diet was supplemented with inorganic selenium (Sodium selenite 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase), group D3 basal diet was supplemented with commercially available organic selenium (Seleno-methionine 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase) and group D4 basal diet was supplemented with self-developed organic selenium (Se-enriched yeast 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase). The performance parameters i.e. feed intake (FI), live body weight (BW) and FCR were not significantly (p>0.05) effected by selenium supplementation in the starter phase but were significantly (p<0.05) effected in the finisher phase. Selenium supplementation significantly (p<0.05) effected serum Se level in different supplemented groups. Higher serum Se value (58.20±0.06) was recorded in D4 group. Similarly significantly lower selenium value was recorded for D4 and higher was recorded for D1 (11.36±0.08). However lower serum Paraoxonase (PON) value was recorded for D4 (13.24±0.01) and higher for D1 (13.33±0.03). Comparatively self-developed Se enriched yeast increased the Se accumulation and improved antioxidant system. Glutathione peroxidase (GPx) was found higher in D4 (12.333±0.03) followed by D3, D2 and D1 respectively. Whereas superoxide dismutase (SOD) was significantly lower (p<0.05) in D4 (0.1437±0.003) followed by D3 (0.1457±0.002). Selenium supplementation increased the bird's survival rate. Birds fed on Se enriched yeast showed higher Se deposition and better antioxidant capacity as compared to other sources of selenium. Se-enriched yeast displayed an improved result on Se deposition in tissues, and oxidative capacity, meat tenderness and immune response level as compared to other sources of selenium.

The use of biological selenium nanoparticles to suppress Triticum aestivum L. crown and root rot diseases induced by Fusarium species and improve yield under drought and heat stress

Fusarium species threaten wheat crops around the world and cause global losses. The global trend is toward using biological materials such as selenium (Se) in nano form to control these fungi. Bulk selenium is toxic and harmful at high doses; however, selenium nanoparticles are safe; therefore, the aim of this study to employ the biological selenium nanoparticles (BioSeNPs) synthesized by Lactobacillus acidophilus ML14 in controlling wheat crown and root rot diseases (CRDs) induced by Fusarium spp., especially Fusarium culmorum and Fusarium graminearum, and their reflection on the growth and productivity of wheat. The ability of BioSeNPs to suppress the development and propagation of F. culmorum and F. graminearum and the CRDs incidence were also investigated. The obtained BioSeNPs were spherical with a size of 46 nm and a net charge of -23.48. The BioSeNPs significantly scavenged 88 and 92% of DPPḢ and ABTṠ radicals and successfully inhibited the fungal growth in the range of 20-40 µg/mL; these biological activities were related to the small size of BioSeNPs and the phenolic content in their suspension. Under greenhouse conditions, the wheat supplemented with BioSeNPs (100 µg/mL) was significantly reduced the incidence of CRDs by 75% and considerably enhanced plant growth, grain quantity and quality by 5-40%. Also, photosynthetic pigments and gas exchange parameters were significantly increased as compared to chemical selenium nanoparticles (Che-SeNPs) and control. This study results could be recommended the use of BioSeNPs (100 µg/mL) in reducing CRDs incidence and severity in wheat plants, enhancing their tolerance with drought and heat stress, and increasing their growth and productivity as compared to control and Che-SeNPs.

Highly stable selenium nanoparticles: Assembly and stabilization via flagellin FliC and porin OmpF in Rahnella aquatilis HX2

Microorganisms play a critical role in the reduction of the more toxic selenite and selenate to the less toxic elemental selenium. However, the assembly process and stability of selenium nanoparticles (SeNPs) remain understudied. The plant growth-promoting rhizobacterium Rahnella aquatilis HX2 can reduce selenite to biogenic SeNPs (BioSeNPs). Two main proteins, namely flagellin FliC and porin OmpF were identified in the BioSeNPs. The fliC and ompF gene mutation experiments demonstrated that the FliC and OmpF could control the assembly of BioSeNPs in vivo. At the same time, the expressed and purified FliC and OmpF could control the assembly of SeNPs in vitro. BioSeNPs produced by R. aquatilis HX2 exhibited high stability under various ionic strengths, while the chemically synthesized SeNPs (CheSeNPs) showed a high level of aggregation. The in vitro experiments verified that FliC and OmpF could prevent the aggregation of the CheSeNPs under various ionic strengths. This work reports the preparation of highly stable BioSeNPs produced by strain R. aquatilis HX2 and verifies that FliC and OmpF both could control the assembly and stability of BioSeNPs. BioSeNPs with high stability could be suitable as nutritional supplement to remedy selenium deficiency and in nanomedicine applications.

Comparison of nanoparticle-selenium, selenium-enriched yeast and sodium selenite on the alleviation of cadmium-induced inflammation via NF-kB/IκB pathway in heart

Cadmium (Cd) has been confirmed as an environmental contaminant, which potential threats health impacts to humans and animals. Selenium (Se) as a beneficial element that alleviates the negative effects of Cd toxicity. Se mainly exists in two forms in food nutrients including organic Se usually as (Se-enriched yeast (SeY)) and inorganic Se (sodium selenite (SSe)). Nanoparticle of Se (Nano-Se), a new form Se, which is synthesized by the bioreduction of Se species, which attracted significant attention recently. However, compared the superiority alleviation effects of Nano-Se, SeY or SSe on Cd-induced toxicity and related mechanisms are still poorly understood. The purpose of this study was to compare the superiority antagonism effects of Nano-Se, SeY and SSe on Cd-induced inflammation response via NF-kB/IκB pathway in the heart. The present study demonstrated that exposed to Cd obviously increased the accumulation of Cd, disruption of ion homeostasis and depressed the ratios of K⁺/Na⁺ and Mg²⁺/Ca²⁺ via ion chromatography mass spectrometry (ICP-MS) detecting the heart specimens. In the results of histological and ultrastructure observation, typical inflammatory infiltrate characteristics and mitochondria and nuclear structure alterations in the hearts of Cd group were confirmed. Cd treatment enhanced the inducible nitric oxide synthase (iNOS) activities and NOS isoforms expression via NF-kB/IκB pathway to promote inflammation response. However, the combined treatment of Cd-exposed animals with Nano-Se was more effective than SeY and SSe in reversing Cd-induced histopathological changes and iNOS activities increased, reducing Cd accumulation and antagonizing Cd-triggered inflammation response via NF-kB/IκB pathway in chicken hearts. Overall, Se applications, especially Nano-Se, can be most efficiently used for relieving cardiotoxicity by exposed to Cd compared to other Se compound.

Nanoselenium and Selenium Yeast Have Minimal Differences on Egg Production and Se Deposition in Laying Hens

The objective of this study was to compare the effects of nanoselenium (NS) and selenium yeast (SY) on the performance, egg selenium (Se) concentration, and anti-oxidative capacity of hens. A total of 216 Brown Hy-line hens (29-week old) were randomly allocated into three treatments (6 replicate/treatment, 12 hens/replicate). The pre-trial period lasted 7 days, and the experimental period lasted 35 days. Dietary treatments included corn-soybean meal basal diet (containing 0.16 μg Se/g, as control group), and basal diet supplemented with 0.3 mg Se/kg diet (Se was from NS or SY), called as SY group or NS group, respectively. At the end of the experiment, one hen per replicate from each treatment was slaughtered. Liver, spleen, and kidney tissues were sampled for the determination of Se concentrations. The results showed that NS or SY supplement significantly improved feed conversion ratio (P < 0.05), soft broken egg rate (P < 0.05), and the serum T-AOC value (P < 0.05) when compared with control group. Remarkably, the deposition of Se increased significantly (P < 0.05) and equivalently in egg, liver, and kidney of hens supplemented with both NS and SY. Interestingly, SY supplement also enhanced the serum CAT and SOD activities (P < 0.05), NS but not SY significantly reduced serum MDA (P < 0.05), whereas RT-PCR results did not show significant differences in the mRNA levels of antioxidant genes among three groups (P > 0.05). Taken together, dietary supplemented with SY or NS improved the Se deposition in eggs, liver and kidney of laying hens, increased antioxidant activity, and NS supplement had greater Se deposition in the kidney tissue than SY supplement. SY or NS supplement could be considered to be applied for Se-enriched egg production.

Advances in Research on the Toxicological Effects of Selenium

Selenium is a trace element necessary for the growth of organisms. Moreover, selenium supplementation can improve the immunity and fertility of the body, as well as its ability to resist oxidation, tumors, heavy metals, and pathogenic microorganisms. However, owing to the duality of selenium, excessive selenium supplementation can cause certain toxic effects on the growth and development of the body and may even result in death in severe cases. At present, increasing attention is being paid to the development and utilization of selenium as a micronutrient, but its potential toxicity tends to be neglected. This study systematically reviews recent research on the toxicological effects of selenium, aiming to provide theoretical references for selenium toxicology-related research and theoretical support for the development of selenium-containing drugs, selenium-enriched dietary supplements, and selenium-enriched foods.

Nano-selenium Supplementation Increases Selenoprotein (Sel) Gene Expression Profiles and Milk Selenium Concentration in Lactating Dairy Cows

Supplementation with selenium is common for dairy cows, but the importance of selenium source is not clear. This study aimed to compare nano-selenium (Nano-Se) and sodium selenite supplements for dairy cows on lactation performance, milk Se levels and selenoprotein (Sel) gene expression. Twelve multiparous Holstein cows were randomly divided into two groups: a control group fed a basal diet plus 0.30 mg Se/kg of DM as sodium selenite or Nano-Se for 30 days. Dry matter intake, milk yield and composition were not affected by dietary Se source (P > 0.05); however, the milk total Se levels and milk glutathione peroxidase (GSH-Px) activities were higher with Nano-Se supplementation than sodium selenite (P < 0.05). At the end of the experiment, Nano-Se supplementation significantly increased plasma Se levels and GSH-Px activity, compared with the sodium selenite supplement. The mRNA expression levels of glutathione peroxidase 1, 2 and 4; thioredoxin reductase 2 and 3; and selenoproteins W, T, K and F were markedly upregulated (P < 0.05) in the mammary gland of the Nano-Se group. Thus, the source of selenium plays an important role in the antioxidant status and in particular the Sel gene expression in the mammary glands of dairy cows, both being stimulated by nano sources.

Potentialities of selenium nanoparticles in biomedical science

Selenium nanoparticles (SeNPs) have revolutionized biomedical domain and are still developing rapidly. Hence, this perspective elaborates SeNPs properties, synthesis, and biomedical applications, together with their potential for management of SARS-CoV-2.

Supplementation of Selenium Nanoparticles-Loaded Chitosan Improves Production Performance, Intestinal Morphology, and Gut Microflora in Broiler Chickens

The current study aimed to evaluate the efficacy of selenium nanoparticles (SeNPs), combined or loaded with chitosan (COS), in broiler chickens reared under standard management protocols. The parameters under investigation were production performance, organ development, components of the intestinal barrier, and ileal microbial count. Two hundred and forty day-old chicks were raised in five groups, with each group containing eight replicates (n=6/replicate). The control group received a basal diet whereas the other four groups received basal diets supplemented with SeNPs (0.5 mg/kg), COS (200 mg/kg), SeNPs+COS (0.5 mg/kg SeNPs + 200 mg/kg COS), and SeNPs-loaded COS (SeNPs-L-COS) (200 mg/kg) respectively. On day 35, two birds/replicate were sampled to collect the viscera under investigation. The results revealed that dietary inclusion of SeNPs-L-COS increased (p<0.05) the body weight gain and improved (p<0.05) feed conversion ratio. Similarly, SeNPs-L-COS supplementation increased (p<0.05) the small intestinal villus surface area as well as the count of acidic goblet cells and intraepithelial lymphocytes when compared with the control group. Whereas the total goblet cell count was higher (p<0.05) in the small intestines of both the SeNPs+COS and SeNPs-L-COS groups. Microbial analysis of ileal contents also revealed an increase (p<0.05) in Lactobacilli species count with a concurrent decrease (p<0.05) in Escherichia coli count in the SeNPs-L-COS group when compared with the COS and control groups. Based on the results of the current trial, we can conclude that supplementation with SeNPs-L-COS is a superior combination for promoting the gut health and performance of broilers.

Sustainable Antibiotic-Free Broiler Meat Production: Current Trends, Challenges, and Possibilities in a Developing Country Perspective

Simple Summary

Chickens are raised with the assistance of the regular use of antibiotics, not only for the prevention and treatment of diseases but, also, for body growth. Overuse and misuse of antibiotics in animals are contributing to the rising threat of antibiotic resistance. Therefore, antibiotic-free broiler meat production is becoming increasingly popular worldwide to meet consumer demand. However, numerous challenges need to be overcome in producing antibiotic-free broiler meat by adopting suitable strategies regarding food safety and chicken welfare issues. This review focuses on the current scenario of antibiotic use, prospects, and challenges in sustainable antibiotic-free broiler meat production. We also discuss the needs and challenges of antibiotic alternatives and provide a future perspective on antibiotic-free broiler meat production.

Abstract

Antibiotic-free broiler meat production is becoming increasingly popular worldwide due to consumer perception that it is superior to conventional broiler meat. Globally, broiler farming impacts the income generation of low-income households, helping to alleviate poverty and secure food in the countryside and in semi-municipal societies. For decades, antibiotics have been utilized in the poultry industry to prevent and treat diseases and promote growth. This practice contributes to the development of drug-resistant bacteria in livestock, including poultry, and humans through the food chain, posing a global public health threat. Additionally, consumer demand for antibiotic-free broiler meat is increasing. However, there are many challenges that need to be overcome by adopting suitable strategies to produce antibiotic-free broiler meat with regards to food safety and chicken welfare issues. Herein, we focus on the importance and current scenario of antibiotic use, prospects, and challenges in the production of sustainable antibiotic-free broiler meat, emphasizing broiler farming in the context of Bangladesh. Moreover, we also discuss the need for and challenges of antibiotic alternatives and provide a future outlook for antibiotic-free broiler meat production.

Nanoselenium effect on growth performance, carcass traits, antioxidant activity, and immune status of broilers

A 42-day comparative study was conducted to assess the impact of nanoselenium to other selenium sources on performance, antioxidant activity, immunity, and carcass traits in broilers. Ross 308 (n = 156) 1-day-old broiler chicks, with average initial body weight of 45.80 ± 0.35, were randomly allocated to 4 groups. The first group (G1) fed the basal diet without selenium supplementation. The second group (G2), the third group (G3), and the fourth group (G4) were supplemented with dietary selenium at the level of 0.3 mg kg^-1 diet in the form of sodium selenite, seleno-methionine, and nanoselenium, respectively. The results revealed significant improvement on most of the performance parameters of nanoselenium at the level of 0.3 mg kg^-1 diet (P < 0.05). Nanoselenium and seleno-methionine achieved the best dressing %, spleen index %, and thymus index %. Concerning to internal organ indices, none of these indices was significantly affected by any selenium sources (P < 0.05). Glutathione peroxidase (GSH-PX) activity and malondialdehyde (MDA) content were not significantly affected by different selenium sources among all experimental groups. Serum interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) showed significant (P < 0.05) decrease in nanoselenium supplemented group compared with other groups. In case of serum IL-10 level, a significant (P < 0.05) increase was reported in nanoselenium supplemented group followed by G3 then G2. There were no statistical differences in the serum alanine transaminase, aspartate transaminase, total protein, albumin concentration, serum creatinine level, and uric acid concentration levels among all experimental groups. It is concluded that nano selenium can be a useful and better source of selenium for broilers.

Influence of bacterial organic selenium on blood parameters, immune response, selenium retention and intestinal morphology of broiler chickens

BACKGROUND

Several studies indicated that dietary organic selenium (Se) usually absorbed better than an inorganic source, with high retention and bioavailability. Dietary Se as an antioxidant element affects the immune system and hematological status in animals. Therefore, the aim of this study was to evaluate the effect of dietary supplementation of bacterial selenium as an organic source on hematology, immunity response, selenium retention, and gut morphology in broiler chickens.

RESULTS

The present results revealed that supplementation of inorganic Se was associated with the lowest level of RBC, HB, and PCV with significant difference than ADS18-Se. In the starter stage, both T2 and T5 were associated with the significantly highest IgG level compared to the basal diet, while all supplemented groups showed higher IgM levels compared to the control group. In the finisher phase, all Se supplemented groups showed significant (P ˂ 0.05) increases in IgG, IgA, and IgM levels compared to T1. Birds fed bacterial-Se showed high intestinal villus height and better Se retention more than sodium selenite. The organic selenium of ADS18 had a superior action in improving Se retention compared to ADS1 and ADS2 bacterial Se.

CONCLUSIONS

Bacterial organic Se had a beneficial effect on the villus height of small intestine led to high Se absorption and retention. Thus, it caused a better effect of Se on hematological parameters and immunity response.

Prophylactic impact of nano-selenium on performance, carcasses quality, and tissues' selenium concentration using reversed-phase high-performance liquid chromatography during microbial challenge in broiler chickens

Background and Aim:

Nano-selenium (NS) supplementation contributes in improving productivity, performance, and meat quality while reducing public health concern. Influence of NS and inorganic selenium (Se) water additive on performance, carcass quality, immunoglobulin concentration, intestinal microbiota, Se tissue concentrations, and tissue architecture was studied.

Materials and Methods:

Two-hundred and sixty 1-day-old Hubbard chicks were randomly grouped into five groups (5×52) and supplemented with 0.5 and 1.0 mL of NS and inorganic Se (100 mg.L⁻¹). G1, G2, G3, and G4 were challenged with Escherichia coli O157: H7 2.6×10⁸ on the 14^th day. A total of 2250 samples, including 250 sera, 250 intestinal swabs, and 1500 organ and tissue samples as liver, spleen, heart, bursa, intestine, and breast muscles, and 250 eviscerated carcasses were collected.

Results:

The results revealed a highly significant increase (p<0.01) in live body weights, weight gains, performance indices, carcasses, and organs weights, whereas immunoglobulin G and M concentrations in broilers treated with 0.5 and 1.0 mL NS, respectively, synchronized reveal a highly significant decline (p<0.01) in total bacterial and Enterobacteriaceae counts of intestinal swabs and breast muscles, final pH₂₄, and drip loss in broilers treated with 0.5 and 1.0 mL NS, respectively. Meanwhile, water holding capacity revealed no significant differences between all groups. Reversed-phase high-performance liquid chromatography examination revealed the earlier disappearance of NS residues than inorganic Se from the broiler’s liver and muscles. Histopathological photomicrographs of the liver, spleen, bursa of Fabricius, and intestine, as well as, the immunohistochemistry of intestinal sections revealed superior tissue architecture in broilers treated with NS contrary to inorganic Se.

Conclusion:

The study showed significant stimulation actions of NS on performance, immunity, carcass and meat quality, intestinal and muscles’ bacterial load as well as short withdrawal period and nearly normal cellular architecture compared to inorganic Se.

Progress and Prospect of Essential Mineral Nanoparticles in Poultry Nutrition and Feeding-a Review

Nanobiotechnology is a growing field in animal and veterinary sciences for various practical applications including diagnostic, therapeutic, and nutritional applications. Recently, nanoforms or nanoparticles (NP) of essential minerals have been explored for growth performance, feed utilization, and health status of animals. Various mineral NP, such as calcium, zinc, copper, selenium, and chromium, have been studied in different farm animals including poultry. Because mineral NP are smaller in size, and show different chemical and physical properties, they are usually absorbed in greater amounts from gastrointestinal tract and exert enhanced biological effects in the target tissues of animals. In various studies, mineral NP have been comparatively studied relating to its larger inorganic and organic particles in poultry. There are contradictory findings among the studies on comparative improvement of production performance and other mineral functions perhaps due to different sizes, shapes, and properties of NP, and interactions of minerals present in basal diets. There are not many studies correlating physical and chemical properties of mineral NP and their biological functions in the body. Nonetheless, it appears that mineral NP have potential for their uses as mineral supplements in preference to inorganic mineral supplements for their better absorption avoiding antagonistic interactions with other minerals, growth performance, and physiological functions, especially at lower doses compared with the doses that are recommended for their larger particles. Supplementation of mineral NP in diets could be a promising option in the future. This review summarizes the studies of different essential mineral NP used as mineral supplements for feed intake, growth performance, egg production and quality, and blood variables in poultry.

Synthesis and comparative assessment of antiradical activity, toxicity, and biodistribution of κ-carrageenan-capped selenium nanoparticles of different size: in vivo and in vitro study

In the present study, water-soluble hybrid selenium-containing nanocomposites have been synthesised via soft oxidation of selenide-anions, preliminarily generated from elemental bulk-selenium in the base-reduction system 'N₂H₄-NaOH'. The nanocomposites obtained consist of Se⁰NPs (4.6-24.5 nm) stabilised by κ-carrageenan biocompatible polysaccharide. The structure of these composite nanomaterials has been proven using complementary physical-chemical methods: X-ray diffraction analysis, transmission electron microscopy, optical spectroscopy, and dynamic light scattering. Optical ranges of 'emission/excitation' of aqueous solutions of nanocomposites with Se⁰NPs of different sizes are established and the most important parameters of their luminescence are determined. For the obtained nanocomposites, the expressed antiradical activity against free radicals 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid has been found, the value of which depends on the size of selenium nanoparticles. It is experimentally revealed that all obtained nanocomposites are low toxic (LD₅₀ >2000 mg/kg). It is also found that small selenium nanoparticles (6.8 nm), in contrast to larger nanoparticles (24.5 nm), are accumulated in organisms to significantly increase the level of selenium in the liver, kidneys, and brain (in lesser amounts) of rats.

Biological Evaluation of Hot-Melt Extruded Nano-selenium and the Role of Selenium on the Expression Profiles of Selenium-Dependent Antioxidant Enzymes in Chickens

A study was conducted to determine the effect of dietary selenium (Se) concentration and source for broiler chickens on performance, nutrient digestibility, plasma Se, glutathione peroxidase (GPx) activity, and thiobarbituric acid reactive substances (TBARS). A total of 700 1-day-old broiler chicks were assigned to 7 diets with 20 birds per cage and 5 replicates per treatment. The experimental diets were fed for 32 days in 2 phases (phase 1, day 0 to 14 and phase 2, day 15 to 32). Treatments were as follows: control (without Se supplementation), sodium selenite (SeS; 0.15, 0.30, or 0.45 ppm), and hot-melt extruded sodium selenite (SeHME; 0.15, 0.30, or 0.45 ppm). There were significant linear responses (P < 0.01) for higher plasma Se concentration in SeS and SeHME treatments. Moreover, an increased (P < 0.01) Se concentration of plasma occurred in SeHME treatment compared with that in SeS treatment. The serum GPx analyses revealed that supplemental SeS and SeHME increased significantly the activity of GPx in the plasma in phase 1 (P < 0.05) and phase 2 (P < 0.05). There were significant linear (P < 0.01) responses of SeS and SeHME treatments for the expression of SelW, GPx1, GPx3, and GPx4 in the livers and spleens. In addition, SeHME showed an upregulated expression of GPx-4 in the livers (P < 0.01) and SelW in the spleens (P < 0.05) compared with SeS treatment. SeHME showed a lower TBARS on day 9. Moreover, a decreased (P < 0.01) TBARS occurred in SeS treatment compared with that in control treatment. In conclusion, SeHME can increase antioxidant activity and Se absorption, consequently being a more suitable source of Se than regular sodium selenite.

Platelet Selenium Indices as Useful Diagnostic Surrogate for Assessment of Selenium Status in Lambs: an Experimental Comparative Study on the Efficacy of Sodium Selenite vs. Selenium Nanoparticles

Unlike in human medicine, information on the platelet selenium (Se) concentration and glutathione peroxidase (GPx) activity, as potential biomarkers of Se status, is lacking in the field of veterinary medicine. The aims of this study were to compare the effects of sodium selenite (SeS) and Se nanoparticles (SeN) on platelet Se indices, and compare the results with those of conventional indices of Se status in sheep. Eighteen lambs with marginal Se status were assigned to a control (CON) group and two Se-treated groups administered either a single dose of Se at 0.055 mg/kg BW subcutaneously as SeS or SeN. The Se concentration and GPx activity in plasma, erythrocytes, whole blood, and platelets were assessed at 14 time points during 90 days. In Se-treated groups, Se concentrations and GPx activity increased significantly in plasma, whole blood, erythrocytes, and platelets. However, the responses in SeS group often started and peaked earlier and, in almost all time points, were more pronounced than the SeN group (P < 0.001), indicating that SeS compared to SeN was more biopotent in raising Se biomarkers. Se indices in platelets started and peaked later than those of short-term (in plasma) and earlier than those of long-term indices (in erythrocytes) indicating that platelet indices can serve as intermediate-term biomarkers of Se status. In conclusion, platelet indices of Se are promising proxy for currently used indices of Se status in sheep, regardless of Se source.

Antioxidant Capacity and Hepatoprotective Role of Chitosan-Stabilized Selenium Nanoparticles in Concanavalin A-Induced Liver Injury in Mice

Selenium nanoparticles (SeNPs) have attracted wide attention for their use in nutritional supplements and nanomedicine applications. However, their potential to protect against autoimmune hepatitis has not been fully investigated, and the role of their antioxidant capacity in hepatoprotection is uncertain. In this study, chitosan-stabilized SeNPs (CS-SeNPs) were prepared by means of rapid ultra-filtration, and then their antioxidant ability and free-radical scavenging capacity were evaluated. The hepatoprotective potential of a spray-dried CS-SeNPs powder against autoimmune liver disease was also studied in the concanavalin A (Con A)-induced liver injury mouse model. CS-SeNPs with size of around 60 nm exhibited acceptable oxygen radical absorbance capacity and were able to scavenge DPPH, superoxide anion, and hydroxyl radicals. The CS-SeNPs powder alleviated Con A-caused hepatocyte necrosis and reduced the elevated levels of serum alanine transaminase, aspartate transaminase, and lactic dehydrogenase in Con A-treated mice. These results suggest that the CS-SeNPs powder protected the mice from Con-A-induced oxidative stress in the liver by retarding lipid oxidation and by boosting the activities of superoxide dismutase, glutathione peroxidase, and catalase, partly because of its ability to improve Se retention. In conclusion, SeNPs present potent hepatoprotective potential against Con A-induced liver damage by enhancing the redox state in the liver; therefore, they deserve further development.

Effect of feeding different sources of selenium on growth performance and antioxidant status of broilers

1. This study was conducted to determine the effect of different sources of selenium (Se) on breast and liver tissue deposition, apparent metabolisable energy (AME), growth performance and antioxidant status of broilers, measured as Se content in liver and breast tissues and glutathione peroxidase (GSH-Px) in blood, when used in 0-35 d broiler chicken diets. 2. A total of 200 male Ross 308 broilers were used in the feeding trial, which comprised two dietary phases, a starter from 0 to 21 d and finisher from 21 to 35 d of age. Four treatments with 10 replications each were used. A control diet (C) was formulated that was sufficient in protein and energy (230 and 215 g/kg of crude protein and 12.67 and 13.11 MJ/kg of metabolisable energy, respectively), for both phases, but contained background Se only from the feed ingredients. Diet 2 (IS) was supplemented with 10.35 g/t inorganic, elemental source of Se. Diet 3 (SY) was supplemented with 136.36 g/t selenised yeast, an organic source derived from Saccharomyces cerevisiae. Diet 4 (SS) was supplemented with 0.666 g/t sodium selenite, an inorganic source. 3. Birds fed the SY diet consumed less and weighed less than those fed IS or C (P < 0.05; 0-35 d of age), but there was no difference compared to birds fed SS diets. There were no differences in FCR or dietary AME between broilers fed different Se sources. All diets containing supplementary Se increased concentrations in the liver and breast muscle, and for GSH-Px levels in blood compared to birds fed the C diet (P < 0.001). Birds fed SY diets had greater Se levels in liver and breast tissues compared to birds fed any of the other diets (P < 0.001). 4. Diets supplemented with Se had variable effects on broiler growth performances and antioxidant status. Feeding Se from a yeast source has higher transfer into breast tissues. Feeding different sources and levels of Se to birds in a more challenging situation to induce oxidative stress may bring more conclusive results.

Comparative study on the responses of broiler chicken to hot and humid environment supplemented with different dietary levels and sources of selenium

Present study was carried out with the objective of investigating the role of green synthesized nano Se (GNS) in growth performance, digestibility of minerals, immunity, stress alleviation, antioxidant status, and body Se content of broiler chicken raised under hot and humid environment with respect to market nano Se (MNS) and inorganic Se. The experimental design was 3 × 3 factorial, in which three levels (0.15, 0.20, and 0.25 ppm) and three sources (inorganic, green nano, and market nano) of Se resulted in nine treatments viz. IS-0.15, GNS-0.15, MNS-0.15, IZ-0.20, GNS-0.20, MNS-0.20, IS-0.25, GNS-0.25, and MNS-0.25 (IS: inorganic Se, GNS: green nano Se, MNS: market nano Se). A total of 432 broiler chicken were divided among nine treatments with six replicates of birds per treatment (8 birds/replicate). Results of present study revealed significantly better growth performance of birds supplemented with 0.25 ppm nano Se. The supplementation of 0.25 ppm nano Se improved the immune response and lymphoid organ development of birds. Significantly higher Se and nitrogen digestibility coefficients, serum antioxidant activity and decline of Heterophil: Lymphocyte ratio and expression of HSP70 gene were observed in birds supplemented with 0.25 ppm Se and nano source of Se compared to inorganic Se. Significantly higher Se concentration in liver and breast muscle and higher serum Se concentration were observed in birds fed 0.25 ppm nano Se. The liver Se concentration was much higher than that of breast muscle. However, the nano Se synthesized by green method in this study did not differ significantly from the chemically synthesized nano Se. It was concluded that 0.25 ppm Se and nano form of Se are superior to lower levels and inorganic form of Se, respectively, in improving the immunity, growth, antioxidant status, and in stress alleviation of broiler chicken. However, GNS is equally efficient as chemically synthesized MNS.