A study on the effects of silver nanoparticles as additive on immune system, blood biochemical properties and intestinal microflora of broiler chicks

Today, the use of antibiotics is limited as a growth promoter. Silver has been known for its antimicrobial properties over the past, and it is said to increase its antimicrobial properties by decreasing the particle size to nano scale. The aim of this study was to evaluate the effect of silver nanoparticles on immune system and blood lipids and microbial population of broiler chickens and compare it with flavomycin. A total 312 day-old broilers (Arbor-Acre Plus) were used in a completely randomized design with 6 treatments diets and 4 replicates per each replicate. The nano-silver solution (2000 ppm) was used in 400 and 800 cc per ton diet or 1000lit water to prepare treatments. Two treatments with and without antibiotic (flavomycin 500g/t) were considered as control groups. Number of monocytes increased significantly in birds received diets or drinking water containing 800 ml silver nanoparticles (p< 0.05). Different levels of silver nanoparticles in diet or drinking water had not significant effects on concentration of cholesterol, low density lipoprotein (LDL) and high density lipoprotein (HDL) of serum and coliform bacteria in the ileum. But the number of cholestridia in the ileum of birds received 800 ml silver nanoparticles in diet or drinking water increased significantly (p< 0.05). The results indicate that silver nanoparticles are not suitable for using as feed additives to encourage immune system and control pathogenic bacteria in broilers gut. Further studies are needed.