Investigation of the Anti-Oxidative Stress Effects of Organic Acid and Silver Nanoparticles Coated on Zeolite in the Liver and Intestine of Broiler Chickens

Introduction: Oxidative stress is one of the major growth-limiting factors that occurs due to the excessive production of reactive oxygen species (ROS) and can lead to tissue damage in vital organs such as the liver and intestine.Due to their antibacterial and antioxidant properties, silver nanoparticles have been proposed as a novel solution for improving animal health and performance.Nanosilver toxicity is closely related to its biotransformation in biological systems, which includes surface oxidation of nanoparticles, release of silver ions, and interaction with biological macromolecules.The use of organic acids as feed additives in poultry nutrition can reduce the need for antibiotics.These effects are mainly due to the antibacterial properties and improved digestive function of these compounds.By reducing the growth of pathogenic bacteria and improving general health, the use of organic acid supplements can be a suitable alternative to antibiotics in poultry nutrition.On the other hand, silver nanoparticles coated on zeolite have high potential in various biological and environmental applications due to the combination of the unique properties of silver nanoparticles and the porous structure of zeolite.Recently, it has been proposed that silver nanoparticles could act as one of the factors inducing oxidative stress and affect the expression of oxidative genes.This research was conducted to investigate the effect of silver nanoparticles coated on zeolite and organic acid on the expression of superoxide dismutase, glutathione peroxidase, and catalase genes in the liver and intestine of broiler chickens.Methods: A total of 450 one-day-old Cobb chicks were divided into five groups subdivided into six replicates, each with 15 chicks, and were kept for 42 days in the same rearing conditions in the form of a completely random design.Experimental diets were 1) a control or basal diet, 2) a basal diet supplemented by 1% clinoptilolite, 3) a basal diet supplemented by 1% clinoptilolite coated with 0.5% nanosilver, a 4) basal diet supplemented by 0.15% organic acid, and 5) a basal diet supplemented by 1% clinoptilolite coated with 0.5% nanosilver and 0.15% organic acid.Silver nanoparticles coated on clinoptilolite were investigated using XRF and FTIR techniques.On day 42, liver and intestine samples were obtained to examine gene expression levels of superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT).For the start (1-21 days of age) and growth (22-42 days of age), diets were adjusted using UFFDA software, and nutritional requirements were prepared according to the recommendations of the Cobb 500 strain maintenance guide.Three biological replicates and three technical replicates were randomly selected on the 42 nd day of the breeding period, and samples were taken from the liver and small intestine (duodenum) to investigate the expression of SOD, GPX, and CAT genes.Data were analyzed using SAS software in a completely randomized design, and means were compared using the Tukey-Kramer test at a probability level of 0.05.Results: In general, the data of this research on the 42 nd day indicated a decreasing effect of experimental treatments, especially nanoparticles, on the relative expression of the tested genes in the liver tissue.A decreasing effect of the experimental treatments was observed on the SOD gene expression, and no significant difference was observed between Z and OA treatments and the control treatment.Moreover, the relative expression of the GPX gene in all experimental