عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Proper feeding is necessary to have appropriate growth, health and also to increase resistance to inappropriate condition such as stressors and diseases. Therefore mineral and vitamin supplements are added to fish diet to improve its growth and health. Food supplements have different roles in diet. These cause better food metabolism, higher hardness and strength of bones, better ionic exchanges and osmotic balance. Iron is an essential element for fish and other vertebrates and there is in all cells. It plays key role in feeding and metabolism. This survey was conducted to evaluate the effects of different levels of Iron nano particle on some growth and feeding parameters in Rainbow trout. 396 rainbow trout fry (Aqualand) were prepared and adapted to new condition. They were feed to saturation with basal diet three times a day for four days. Then fish were divided in to 6 treatments. Different levels of Iron nano particle (0, 15, 30, 45 and 60 mg/Kg) and also 60 mg/ kg ferrous sulfate were added to basal diets for each treatments. Fish were feed for eight weeks. Effects of Iron were studied on fish growth. Results showed that 30mg/Kg Iron nano particle improved feeding and growth performance of rainbow trout fry.