Assessment of the role of silver nanoparticles in reducing poultry mortality, risk and economic benefits

Silver Nanoparticles as Antimicrobial Agents in Veterinary Medicine: Current Applications and Future Perspectives

Silver nanoparticles (AgNPs) have gained significant attention in veterinary medicine due to their antimicrobial properties and potential therapeutic applications. Silver has long been recognized for its ability to combat a wide range of pathogens, and when engineered at the nanoscale, silver's surface area and reactivity are greatly enhanced, making it highly effective against bacteria, viruses, and fungi. This narrative review aimed to summarize the evidence on the antimicrobial properties of AgNPs and their current and potential clinical applications in veterinary medicine. The antimicrobial action of AgNPs involves several mechanisms, including, among others, the release of silver ions, disruption of cell membranes and envelopes, induction of oxidative stress, inhibition of pathogens' replication, and DNA damage. Their size, shape, surface charge, and concentration influence their efficacy against bacteria, viruses, and fungi. As a result, the use of AgNPs has been explored in animals for infection prevention and treatment in some areas, such as wound care, coating of surgical implants, animal reproduction, and airway infections. They have also shown promise in preventing biofilm formation, a major challenge in treating chronic bacterial infections. Additionally, AgNPs have been studied for their potential use in animal feed as a supplement to enhance animal health and growth. Research suggested that AgNPs could stimulate immune responses and improve the gut microbiota of livestock, potentially reducing the need for antibiotics in animal husbandry. Despite their promising applications, further research is necessary to fully understand the safety, efficacy, and long-term effects of AgNPs on animals, humans, and the environment.

Use of Metallic Nanoparticles Against Eimeria-the Coccidiosis-Causing Agents: A Comprehensive Review

Coccidiosis is a protozoan disease caused by Eimeria species and is a major threat to the poultry industry. Different anti-coccidial drugs (diclazuril, amprolium, halofuginone, ionophores, sulphaquinoxaline, clopidol, and ethopabate) and vaccines have been used for their control. Still, due to the development of resistance, their efficacy has been limited. It is continuously damaging the economy of the poultry industry because under its control, almost $14 billion is spent, globally. Recent research has been introducing better and more effective control of coccidiosis by using metallic and metallic oxide nanoparticles. Zinc, zinc oxide, copper, copper oxide, silver, iron, and iron oxide are commonly used because of their drug delivery mechanism. These nanoparticles combined with other drugs enhance the effect of these drugs and give their better results. Moreover, by using nanotechnology, the resistance issue is also solved because by using several mechanisms at a time, protozoa cannot evolve and thus resistance cannot develop. Green nanotechnology has been giving better results due to its less toxic effects. Utilization of metallic and metallic oxide nanoparticles may present a new, profitable, and economical method of controlling chicken coccidiosis, thus by changing established treatment approaches and improving the health and production of chickens. Thus, the objective of this review is to discuss about economic burden of avian coccidiosis, zinc, zinc oxide, iron, iron oxide, copper, copper oxide, silver nanoparticles use in the treatment of coccidiosis, their benefits, and toxicity.

A systematic review on the role of biosecurity to prevent or control colibacillosis in broiler production

This systematic review aimed at investigating the role that biosecurity can have in preventing or controlling colibacillosis in broiler production. Primary studies with natural or experimental exposure to avian pathogenic Escherichia coli, evaluating any biosecurity measure to prevent or control colibacillosis in broiler chickens with at least one of the following outcomes: feed conversion ratio (FCR), condemnations at slaughter, and mortality due to colibacillosis, were included. A systematic search was carried out in 4 databases according to the Cochrane handbook and reported following the PRISMA 2020 directions. Studies (n = 3,886) were screened in a 2-phase process and data matching the inclusion criteria were extracted. Risk of bias assessment was performed. Four studies reporting biosecurity measures to prevent or control colibacillosis in broiler production were included. In all studies, only disinfection during either the pre-hatching period (n = 3) or the post-hatching period (n = 1) was evaluated as biosecurity measure in broiler production, as well as its effect on FCR (n = 2) and mortality (n = 4) due to colibacillosis. No studies with effects on condemnations at slaughter were found. Due to the heterogeneity of studies in regard to interventions and outcomes, meta-analysis was not carried out. The limited findings of this systematic review do not provide a comprehensive evidence to statistically evaluate the efficacy of biosecurity to prevent or control colibacillosis in broiler production. The scarcity of evidence found suggests that further and deeper investigations on the topic are needed, considering the variety of interventions related to biosecurity.

Nanosilver-based materials as feed additives: Evaluation of their transformations along in vitro gastrointestinal digestion in pigs and chickens by using an ICP-MS based analytical platform

The use of a new nanomaterial in the feed chain requires a risk assessment that involves in vitro gastrointestinal digestions to predict its degradation and oral exposure to nanoparticles. In this study, a nanosilver-based material was incorporated into pig and chicken feed as a growth-promoting additive and subjected to the corresponding in vitro gastrointestinal digestions. An inductively coupled plasma mass spectroscopy (ICP-MS) analytical platform was used to obtain information about the silver released in the different digestion phases. It included conventional ICP-MS for total silver determination, but also single particle ICP-MS and coupling to hydrodynamic chromatography for detection of dissolved and particulate silver. The bioaccessible fraction in the intestinal phase accounted for 8-13% of the total silver, mainly in the form of dissolved Ag(I) species, with less than 0.1% as silver-containing particles. Despite the additive behaving differently in pig and chicken digestions, the feed matrix played a relevant role in the fate of the silver.

Chitosan coating silver nanoparticles as a promising feed additive in broilers chicken

The present study aimed to evaluate the potential of chitosan coating silver nanoparticles to enhance the growth performance and immune status of broilers without inducing oxidative stress-related pathological lesions in any organs or leaving residues of silver in the edible parts. Five clusters of Cobb one-day-old chicks (n = 10/group in each replication) were given oral therapy, once a week for 36 days as follows: (1) distilled water, (2, 3) 0.5- and 5 ppm silver nanoparticles (AgNPs), respectively, (4, 5) 0.5- and 5 ppm chitosan/silver nanoconjugates (CS/Ag-NCs), respectively. The results demonstrated a marked elevation in the body weight gain with a decline in the food conversion ratio and marked improvement in feeding and drinking behavior of all nanoparticles treated groups, but higher in CS/Ag-NCs groups than AgNPs groups and control group. In contrast to the 0.5 ppm AgNPs receiving group, the group receiving 5 ppm AgNPs noticed remarkable histological changes in some organs, including the liver, kidneys, spleen, and heart. Moreover, the administration of CS/Ag-NCs at two dosage levels didn't influence any histological changes. The AgNPs groups' antibody titers against the ND and AI viruses were almost identical to those of the control group. Otherwise, CS/Ag-NCs groups recorded the highest antibody titers. Additionally, there was a significant increase in silver content in most edible organs of AgNPs groups at a dosage level of 5 ppm. Otherwise, the coating of AgNPs by CSNPs could decrease the aggregation of silver in the biological organs. Thus, we recommend utilizing 0.5 ppm CS/Ag-NCs in broiler farms to promote their growth performance and strengthen their immune defense.

Enhanced photocatalytic and antibacterial activities of novel Ag-HA bioceramic nanocatalyst for waste-water treatment

Hydroxyapatite (HA), the most common bioceramic material, offers attractive properties as a catalyst support. Highly crystalline mono-dispersed silver doped hydroxyapatite (Ag-HA) nanorods of 60 nm length was developed via hydrothermal processing. Silver dopant offered enhanced chemisorption for crystal violet (CV) contaminant. Silver was found to intensify negative charge on the catalyst surface; in this regard enhanced chemisorption of positively charged contaminants was accomplished. Silver dopant experienced decrease in the binding energy of valence electron for oxygen, calcium, and phosphorous using X-ray photoelectron spectroscopy XPS/ESCA; this finding could promote electron-hole generation and light absorption. Removal efficiency of Ag-HA nanocomposite for CV reached 88% after the synergistic effect with 1.0 mM H2O2; silver dopant could initiate H2O2 cleavage and intensify the release of active ȮH radicals. Whereas HA suffers from lack of microbial resistance; Ag-HA nanocomposite demonstrated high activity against Gram-positive (S. aureus) bacteria with zone of inhibition (ZOI) mm value of 18.0 mm, and high biofilm inhibition of 91.1%. Ag-HA nanocompsite experienced distinctive characerisitcs for utilization as green bioceramic photocatalyst for wastewater treatment.

The effect of metal-containing nanoparticles on the health, performance and production of livestock animals and poultry

The application of high doses of mineral feed additives in the form of inorganic salts increases the growth performance of animals, but at the same, due to their low bioavailability, can contaminate the environment. Therefore, there is a need to find a replacement of administering high doses of minerals with an equally effective alternative. The application of lower doses of metal-containing nanoparticles with the same effect on animal production could be a potential solution. In the present review, zinc, silver, copper, gold, selenium, and calcium nanoparticles are discussed as potential feed additives for animals. Production of nanoparticles under laboratory conditions using traditional chemical and physical methods as well as green and sustainable methods - biosynthesis has been described. Special attention has been paid to the biological properties of nanoparticles, as well as their effect on animal health and performance. Nano-minerals supplemented to animal feed (poultry, pigs, ruminants, rabbits) acting as growth-promoting, immune-stimulating and antimicrobial agents have been highlighted. Metal nanoparticles are known to exert a positive effect on animal performance, productivity, carcass traits through blood homeostasis maintenance, intestinal microflora, oxidative damage prevention, enhancement of immune responses, etc. Metal-containing nanoparticles can also be a solution for nutrient deficiencies in animals (higher bioavailability and absorption) and can enrich animal products with microelements like meat, milk, or eggs. Metal-containing nanoparticles are proposed to partially replace inorganic salts as feed additives. However, issues related to their potential toxicity and safety to livestock animals, poultry, humans, and the environment should be carefully investigated.

Evaluation of the Effects of Silver Nanoparticles Against Experimentally Induced Necrotic Enteritis in Broiler Chickens

Background

Clostridium perfringens-associated necrotic enteritis (NE) is a serious problem affecting broiler production. A major global challenge is to reduce the use of antibiotics in poultry industry due to their negative impacts on public health. One alternative is to use nanoparticles (NPs) to overcome bacterial resistance to antibiotics. Silver nanoparticles (Ag NPs) showed strong antimicrobial activity.

Methods

A total of 120 Cobb broiler chicks (1-day old) were obtained for this study and were divided into 4 equal groups at age of 14 days (30 birds each); each group was subdivided into 3 equal replicates (10 birds each). The groups were designated as follows: G1, infected; G2, infected and treated with Ag NPs; G3, treated with Ag NPs; and G4, negative control. Birds were infected with 4×10⁸ colony forming unit (CFU)/mL/bird C. perfringens type A for 2 successive days. In the treated groups, Ag NPs (mean diameter 15 nm; total dose 150 µg/bird) were administered via crop gavage. During the observation period (5 weeks), bird performance and immune organ indexes were recorded. Serum samples were collected for immunological evaluation, and tissue samples were collected for histopathology and estimation of Ag NPs residues.

Results

Treatment with Ag NPs reduced the colonization of C. perfringens in the intestine and ceca, decreased the severity of clinical signs and reduced mortalities in comparison with infected non-treated group. Ag NPs treatment alleviated pathological lesions in the intestine and liver, but their residues were found in the muscles.

Conclusion

Ag NPs have a positive impact on gut health integrity while having no impact on immune organs. Ag NPs have some residues in muscles; therefore, further studies are needed on the concentration and size of Ag NPs, the route of administration, and withdrawal time to ensure the safety of chicken meat for human consumption.

Influence of preparation of silver nanoparticles in carriers based on polymer/inorganic hybrids on the mineral composition of chicken eggs

The solution to the problem of reducing the use of antibiotics in the production of edible eggs is possible through the development and use of alternative bactericidal preparations, including those based on nanosilver. Obtaining biocompatible and biodegradable polymer/inorganic carriers of nanosilver provides for the study of its cumulative qualities which determine the safety of edible chicken eggs. The study investigated the mineral composition of edible eggs when feeding Hy-Line W36 laying hens solutions of the nanosilver preparation in carriers based on polymer/inorganic hybrids (AgNPs/SPH) given in the concentrations of 0, 1.0, and 2.0 mg/L of water (0, 0.2 and 0.4 mg/hen per day) three times at 10 day intervals. Oral administration to laying hens of an aqueous solution of silver nanoparticles in carriers based on polymer/inorganic hybrids at doses of 0.2 and 0.4 mg per hen per day in a dose-dependent manner increased the silver content and did not significantly affect the content of copper, zinc, iron, and lead in the eggshell. The preparation of silver nanoparticles did not affect the content of silver, copper, zinc, iron and lead in the albumen and yolk of chicken eggs after the first and second application, and after the third treatment of laying hens contributed to an increase in the silver content in the egg albumen and yolk but did not affect the content in them of copper, zinc, iron and lead. A single feeding of a solution of a preparation of nanosilver in carriers based on polymer/inorganic hybrids to hens at doses of 0.2 and 0.4 mg per hen per day after 10 days, contributed to a significant increase in the yolks of chicken eggs due to a decrease in the albumen and eggshell. The second and third application of nanosilver to poultry in the indicated doses contributed to a decrease in its proportion in the albumen and in the yolk due to a significant increase in its proportion in the shell. Selective accumulation of in-shell silver can be a promising means of improving the safety and security of chicken eggs when they are microbially contaminated. The results of using nanosilver based on polymer/inorganic hybrids in laying hens can be the basis for the development of methods for increasing the bactericidal properties of the shell and the safety of edible eggs.

Oral administration of silver nanoparticles-adorned starch as a growth promotor in poultry: Immunological and histopathological study

Silver nanoparticles (AgNPs) have recently emerged as promising growth promoters and immune-lifting agents in the poultry industry. This study investigated the potential impact of AgNP supplementation in the drinking water (DW) of broiler chickens during the fattening period. AgNPs were produced through chemical reduction using starch as a reducing and stabilizing agent. Different concentrations (1-5 ppm) of AgNPs were prepared and added to the DW of five different groups of chickens. Results confirmed efficient and safe application of AgNPs in DW at concentrations up to 2 ppm in term of growth performance (body weight, body weight gain, and feed conversion ratio) and hematological parameters. However, higher concentrations (3-5 ppm) induced dose-dependent mild-to-moderate adverse effects on hematological, biochemical, and oxidative parameters (MDA, TAC, and GSH-px). While growth performance, gene expression of fibroblast growth factor 2 (FGF2), vascular endothelial growth factor A (VEGFA),and insulin-like growth factor (IGF1) in muscle, histopathological and immunohistochemical evaluation of liver, kidney, spleen, bursa, and thymus, and ultrastructural analysis of breast muscle were not significantly affected, even at high concentrations of AgNPs. Therefore, supplementation of AgNPs up to 2 ppm in the DW of broilers is promising.

Evaluation of bone marrow hemopoiesis and the elemental status of the red bone marrow of chickens under introduction of copper to the organism

The role of chemical elements in an organism is versatile and multifunctional. However, you should pay attention to the reaction of the organism on the introduction of chemical elements with different biological roles, which is predetermined by the physiological role of organs and body systems. These include the red bone marrow, which primarily responds to endogenous and exogenous factors by its functional significance. Analyzing the myelogram of birds after the various ways of copper NP introduction into the body and the different dosages, we found that, by the end of the experiment, the total numbers of bone marrow cells in all groups were lower than the initial values: in the second group-12.54% lower (p < 0.05), in third-26.32% lower (p < 0.001), for the fourth-14.75% lower (p < 0.05), with exception for the first experimental group where this index was 45.51% higher (р < 0.001). We revealed the following changes in the peripheral blood: the hemoglobin content by the end of the experiment was significantly higher than the initial values: by 18.63% for the first group (p < 0.01); 28.61% higher in the third group (p < 0.001); and 15.76% higher for the fourth (p < 0.01), except the animals of the second group (3.23% lower). The concentration of erythrocytes in all groups was higher than that of the background: by 24.56% (p < 0.001), by 3.37%, by 26.18% (p < 0.001), and by 14.85% (p < 0.01), respectively; the leukocyte concentration in the first group was 39.63% higher (p < 0.001), it remained at the level of the initial values in the other groups. The erythrocyte sedimentation rate in all groups increased by 2.4, 4.0, 2.01, and 1.86 times (p < 0.001), respectively. We revealed that the introduction of copper into an organism in the form of nanopowder both with feed and intramuscularly significantly caused an increase of the content of such elements as arsenic, copper, and silicon and a decrease of calcium, potassium, magnesium, phosphorus, boron, cobalt, iodine, lithium, sodium, zinc, tin, and strontium in the marrowy aspirate. Moreover, compared with the first group (p < 0.01), increasing doses of nanopowders caused a significant rise in the arsenic and tin concentrations and a decline of iodine and strontium. We found that copper nanoparticles ambiguously affect the bone marrow hemopoiesis of poultry; increasing the dose and changing the type of introduction activating the bone marrow hematopoietic function, in particular, granulocyto-, megakaryocyto-, and erythropoiesis.

Growth, serum biochemical, and histopathological responses of broilers administered with silver nanoparticles as a drinking water disinfectant

The supplementation of 50 ppm dosed silver nanoparticles (AgNPs) as a disinfectant in broilers drinking water was investigated to examine their growth performance, blood serum biochemistry, and organ histology in the case group, compared to the control. The growth performance parameters, such as water intake, feed intake, and body weight were recorded 6 times, each in an interval of 7 days, over a period of 42 days. At the end of each 42 days, the blood and major organs of the 1 case boiler out of 75 and 1 control broiler out of 75 were collected in random. The procedure was repeated 3 sets one after another, each consisting 42 day intervening period. The liver enzyme, lipid profile, glucose level, organ histology, and concentration of AgNPs in liver, spleen, heart, and small intestine were determined. The obtained results show that the growth performance of the case broilers was significantly higher than the control section (p < 0.05). However, in all the three sets the changes in lipid profile, liver enzyme, and glucose level of the case broilers were not statistically significantly different compared to the control (p > 0.05). The histology of liver, kidney, heart, spleen, and small intestine of broilers has not shown any damages to the cells as compared to the control samples. In the case samples, the highest concentration of AgNPs was observed in the small intestine (5.44 µg/g) followed by liver (4.32 µg/g), kidney (3.94 µg/g), heart (3.82 µg/g), and spleen (3.49 µg/g). The present study concludes that the administering 50 ppm AgNPs of average 15 nm size in the poultry drinking water was found safe for consumption as well as for growth enhancing, due to better bird comfort.