Response of Anti-Oxidative Stress Genes in Liver and Intestine in Broilers Fed Organic Acid and Silver Nanoparticles Coated on Zeolite in Starter Period

Background: The use of food supplements to improve growth, optimal production and increase feed efficiency in feeding livestock and poultry has become a common thing as a suitable solution in using feed as well as possible.Along with the progress of the nano industry, attention has been paid to nanoparticles, especially silver nanoparticles, as an antibacterial agent and growth promoter.Silver nanoparticles can be considered as growth stimulating antibiotics and affect the growth and health of livestock and poultry.The mechanism of the effect of silver on pathogenic cells can be due to the high absorption capacity of silver ions, which immediately enters the bacterial cell membrane and makes the cell membrane leaky.On the other hand, organic acids and their salts have found a special place as an additive in livestock and poultry nutrition, and by having growth stimulating effects, they are known as a suitable alternative to antibiotics.The use of organic acids supplement improved the performance of broiler chickens by improving feed consumption, digestion and absorption, reducing the production of toxic substances and increasing favorable intestinal microorganisms, reducing the occurrence of infections and modulating the immune response of poultry.Also, zeolite is a mineral material of hydrated aluminosilicates, which has a three-dimensional and highly porous crystalline structure and contains alkaline elements such as potassium, sodium, calcium, and magnesium.Recently, it has been proposed that silver nanoparticles can act as one of the factors inducing oxidative stress and affect the expression of oxidative genes.This research was conducted with the aim of investigating the effect of silver nanoparticles coated on zeolite and organic acid on the relative expression of superoxide dismutase, glutathione peroxidase and catalase genes in the liver of broiler chickens.Methods: This experiment was conducted using 450 broiler chickens in five treatments and six replications and 15 broiler chickens in each experimental unit in a completely randomized design at the Poultry Research Station of Gorgan University of Agricultural Sciences and Natural Resources.Their nutritional requirements for the starter periods (1-21 days) were prepared according to the recommendation of the Cobb 500 strain maintenance guide and the food rations were adjusted using the UFFDA software.Experimental treatments include: 1) control treatment, 2) control treatment supplemented with 1% zeolite, 3) control treatment supplemented with 1% zeolite coated with 0.5% nanosilver, 4) control treatment supplemented with 0.15% The percentage of organic acid and 5) control treatment supplemented with 1% zeolite covered in 0.5% nanosilver and 0.15% organic acid.The composition and properties of silver nanoparticles were determined by Fourier transform infrared spectroscopy (FTIR) and Xray diffraction analysis (XRD).To perform molecular tests, total RNA was first extracted using TRIzol extraction kit (Sigma Aldrich) and 1% agarose gel was used to determine the quality of RNA extracted from tissues.On the 21 st day of breeding period, randomly from 3 biological replicates and 3 technical replicates, a piece of 1 cm long was separated from the liver and small intestine tissue and after transferring to a microtube, to check the relative expression of