Exploring the potential to improve the gut microbiome of broiler chickens using selenium nanoparticle supplements

The poultry industry has rapidly grown in the last few years with a focus in improving growth and productivity of broiler chickens, with performance assessed on measures such as feed conversion ratio, body weight gain and good immunity. The incorporation of antibiotics and feed additives in poultry diets, have been implemented for years to ensure the maintenance of poultry health with a focus on the control and reduction of zoonotic pathogens. In the last few years, however, key issues surrounding the antimicrobial resistance of antibiotics have urged for alternative supplementations. Nanoparticles (NPs) of silver and other metals have been heavily used in the poultry industry to improve the growth and performance of birds. Whilst successful, metal NPs exhibited higher toxicity at the higher surface to volume ratio, especially with the use of silver. This study proposes the use of NPs of essential metals and natural compounds to safely deliver nutrients, resulting in positive impacts on health and productivity with little to no toxic effects. Selenium is an essential mineral, required for the proper functioning of the immunity and is an important element in the first cell line of defence in the body. The work described in this thesis explores the ability of selenium NPs to improve the health and growth of broiler chickens by modulating their gut microbiome and metabolome, without the toxic effects observed with silver. Selenium NPs were synthesised using a simple chemical reduction method and a full characterisation was performed, assessing the physicochemical properties of the NP. Selenium NPs were then compared in an animal trial against two commonly used selenium additives in the poultry industry, sodium selenite (inorganic selenium) and selenomethionine (organic selenium). The performance of the birds was assessed based on body weight gain, the gut microbial composition and metabolite production. The toxicity of NPs was further investigated by quantifying selenium concentration in various tissues, along with a detailed histopathological assessment. Results show selenium NPs completely altered the gut microbial ecology at high concentration, with a strong correlation observed between Faecalibacterium prausnitzii abundance and increasing concentration of selenium NPs. Selenium NPs additionally increased villus height/crypt ratio associated with enhanced absorption in the small intestine and an overall increase of healthy colonic metabolites. Finally, an in vitro study demonstrated the ability of selenium NPs to reduce emerging pathogenic Enterococcus cecorum species. This thesis demonstrates the prospective ability of selenium NPs as alternatives to antibiotics and bulk supplementation, resulting in an improvement of health and performance of broiler chickens in the poultry industry

Emerging biomaterials and strategies for medical applications : a review

The creation of new materials is one of the fundamental driving forces between research andindustry and lays the foundation for new products to enhance health and well being for the future.Antibacterial materials are an active area of research but also an economic sector in fullexpansion that addresses many application domains. It is also a world priority in terms ofreducing infection in humans for improved life and well being. Healthcare is one the largest andmost rapidly expanding needs of modern society, and smart approaches and materials arerequired to extend the boundaries required to improve the field. In this paper, we systematicallyreview a series of biomaterials and strategies that have emerged over the last decade. Inparticular, focus has been driven around the nanorealm. Some of the diverse arenas surroundingthe nanodomain and applications include drug screening technologies, biocompatibility,emerging approaches and biomimetics. In a wider front, intelligent materials are where the nextphases of research are driven, some of which are discussed herein

Nanoparticle and biomaterial characterisation techniques

The physicochemical properties of nanoparticles and biomaterials exert influences over their interactions with cells and consequently play an important role when introduced into any given system. Characterisation of these said materials is a detailed and, above all, a cross-disciplinary relationship of physical, chemical, mechanical, surface, in vitro and in vivo multi-integrated research topics. The biocompatibility of a functional structure with desired properties is affected by the biomaterials' structural characteristics and building block pathways. Moreover, the sensitivity, depth of field, resolution and dimension of a given material also make structural analysis of a nano-biomaterial particularly challenging to characterise. In this paper, we discuss the use of biomaterial characterisation techniques (fluorescent and optical) to characterise structural aspects of biomaterials, with the aim of improving both the understanding and relationship between a biomaterial's structure and its functionality

From replacement to regeneration: Are bio-nanomaterials the emerging prospect for therapy of defective joints and bones?

Healthcare is now regarded as one of the largest costs to any government budget and thus innovative ideas are sought as a means to reduce this spiralling bill. A significant proportion of this expenditure relates to specialised consultative care and post-operative therapy. In order to both mitigate the expense and improve the long-term effectiveness of orthopaedic surgery, including arthroplasty, the conception and creation of new biomaterials for treatment of defective joints and bones in the human body has become an emerging area of translational research over the last decade. In this review, we discuss a series of novel biomaterials and strategies for their therapeutic use that have arisen recently as viable approaches to regenerative medicine

The synthesis and characterisation of highly stable and reproducible selenium nanoparticles

This paper describes a simple and reproducible solution phase synthesis approach for selenium nanoparticles by reducing selenium tetrachloride in the presence of ascorbic acid. An optimization study with poly (sodium 4-styrenesulfonate) produced stable and spherical narrowly size distributed nanoparticles (46 nm) which are considered highly monodisperse. The presence of selenium nanoparticles was confirmed by UV-visible spectroscopy for surface plasmon resonance (262 nm), elemental dispersive spectroscopy (11 KeV and 12.5 KeV) and size ranges characterized by dynamic light scattering (PDI = 0.04, the ​size range of optimized nanoparticles = 35 nm to 75 nm), and visualized using scanning and transmission electron microscopy

Nanoparticles in feed: Progress and prospects in poultry research

© 2016 Elsevier LtdThe global poultry industry has greatly expanded due to an increase in demand for chicken meat and eggs. Growth of the industry was followed by growth in research which resulted in improved growth rate, feed efficiency, health status, and reduced carriage of pathogens. However, major research focus was improvement in productivity. It is possible to manipulate feed formulations to improve the feed conversion ratio (FCR), which results in a lower feed requirement to achieve market weight. Feed additives, containing vitamins and minerals, are commonly added to typical diets to support rapid growth and favourable FCR. Nanoparticles can be added to feed and provide an excellent platform to incorporate in various compounds, such as vaccines and nutrient supplements, due to large surface area to volume ratio and high absorption in the body. Nanoparticles can enable direct transportation of compounds to targeted organs or systems while avoiding fast degradability often seen with antibiotics and can encourage multiple health benefits. Silver, currently the most common nanoparticle investigated for use in chicken feed, has been shown to improve the microbiota of chickens. However, the positive results are tempered by the finding that silver nanoparticles have relatively high toxicity in birds. The question therefore arises as to whether other nanoparticle forms of essential metals and natural compounds can be safely delivered to provide positive impacts on health and productivity without the toxic side effects that can be seen with silver nanoparticles. Here, we review the current state of nanoparticle use as a poultry feed supplement - the successes and pitfalls of nano-feed as reported by researchers across the world

Oregano powder reduces Streptococcus and increases SCFA concentration in a mixed bacterial culture assay

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Food borne illnesses have a world-wide economic impact and industries are continuously developing technologies to reduce the spread of disease caused by microorganisms. Antimicrobial growth promoters (AGPs) have been used to decrease microbiological infections in animals and their potential transfer to humans. In recent years there has been a global trend to remove AGPs from animal feed in an attempt to reduce the spread of antimicrobial resistant genes into the human population. Phytobiotics, such as oregano powder, are one of the potential replacements for AGPs due to their well-established antimicrobial components. 16S rRNA gene amplicons were used to determine the effect of oregano powder (1% w/v) on the microbiota of mixed bacterial cell cultures, which were obtained from the ceca of traditionally grown meat chickens (broilers). Oregano powder had a mild effect on the microbial cell cultures increasing Enterococcus faecium, rearranging ratios of members in the genus Lactobacillus and significantly reducing the genus Streptococcus (p = 1.6e-3). Beneficial short chain fatty acids (SCFA), acetic and butyric acid, were also significantly increased in oregano powder supplemented cultures. These results suggest that oregano powder at a concentration of 1% (w/v) may have beneficial influences on mixed microbial communities and SCFA production. © 2019 Bauer et al

A review of methods for the detection of pathogenic microorganisms

The testing and rapid detection of pathogenic organisms is a crucial protocol in the prevention and identification of crises related to health, safety and wellbeing. Pathogen detection has become one of the most challenging aspects in the food and water industries, because of the rapid spread of waterborne and foodborne diseases in the community and at significant costs. With the prospect of inevitable population growth, and an influx of tourism to certain water bodies testing will become a requirement to control and prevent possible outbreaks of potentially fatal illnesses. The legislation is already particularly rigorous in the food industry, where failure to detect pathogenic materials represents a catastrophic event, particularly for the elderly, very young or immune-compromised population types. In spite of the need and requirement for rapid analytical testing, conventional and standard bacterial detection assays may take up to seven days to yield a result. Given the advent of new technologies, biosensors, chemical knowledge and miniaturisation of instrumentation this timescale is not acceptable. This review presents an opportunity to fill a knowledge gap for an extremely important research area; discussing the main techniques, biology, chemistry, miniaturisation, sensing and the emerging state-of-the-art research and developments for detection of pathogens in food, water, blood and faecal samples. © 2019 The Royal Society of Chemistry

In vitro growth of gut microbiota with selenium nanoparticles

The application of nanoparticles rose steeply in the last decade, where they have become a common ingredient used in processed human food, improving food properties such as shelf life and appearance. Nanoparticles have also attracted considerable interest to the livestock industry, due to their efficacy in intestinal pathogen control, with the regulatory and consumer driven push for the removal of antibiotic growth promoters. The influence of selenium (Se) nanoparticles was investigated on a diverse and mature broiler caecal microbiota using in vitro culturing and 16S rRNA gene sequencing methods for microbiota characterisation. Caecal microbiota was collected from 4 traditionally grown heritage roosters and grown for 48 h, in the presence and absence of Se nanoparticles, with 2 technical replicates each. The effect of rooster as a biological variable strongly overpowered the effects of nano-Se in the media, resulting in moderate effects on the structure and diversity of the caecal microbial community. However the nanoparticles showed a significant reduction (P < 0.05) in the abundance of an emerging poultry pathogen, Enterococcus cecorum identical operational taxonomic units (OTU), which could be of notable interest in poultry production for targeted E. cecorum control without significant disturbance to the total microbial community. © 2019 Chinese Association of Animal Science and Veterinary Medicin

Selenium nanoparticles in poultry feed modify gut microbiota and increase abundance of Faecalibacterium prausnitzii

© 2017, Springer-Verlag GmbH Germany, part of Springer Nature. The poultry industry aims to improve productivity while maintaining the health and welfare of flocks. Pathogen control has been achieved through biosecurity, vaccinations and the use of antibiotics. However, the emergence of antibiotic resistance, in animal and human pathogens, has prompted researchers and chicken growers alike to seek alternative approaches. The use of new and emerging approaches to combat pathogen activity including nanotechnology, in particular, silver nanoparticles (NPs), has been found to not only eradicate pathogenic bacteria but also include issues of toxicity and bioaccumulation effects. Other novel metal nanoparticles could provide this pathogen reducing property with a more tailored and biocompatible nanomaterial for the model used, something our study represents. This study investigated the benefits of nanomaterial delivery mechanisms coupled with important health constituents using selenium as a biocompatible metal to minimise toxicity properties. Selenium NPs were compared to two common forms of bulk selenium macronutrients already used in the poultry industry. An intermediate concentration of selenium nanoparticles (0.9 mg/kg) demonstrated the best performance, improving the gut health by increasing the abundance of beneficial bacteria, such as Lactobacillus and Faecalibacterium, and short-chain fatty acids (SCFAs), in particular butyric acid. SCFAs are metabolites produced by the intestinal tract and are used as an energy source for colonic cells and other important bodily functions. Selenium nanoparticles had no significant effect on live weight gain or abundance of potentially pathogenic bacteria