The Effects of Using Dietary Lactobacillus plantarum and Lactoferrin on the Growth Parameters in Rainbow Trout (Onchorhynchusmykiss)

Use of growth and feeding stimulators have proven to have an important role in the development of aquaculture industry. In this study, we investigated the effect of Lactobacillus plantarum (L. plantarum) and lactoferrin on growth and feeding indices of rainbow trout (Oncorhynchusmykiss). 900 fish (average weight 20±2 g) were divided into 6 feeding treatments supplemented with different doses of L. plantarum and lactoferrin and were fed for two months. Growth and feeding parameters including wet weight (wet W), standard length (SL), feed conversion ratio (FCR), specific growth rate (SGR) and condition factor (CF) were measured on days 0, 15, 30, 45 and 60 and compared with the control group. The results showed that treatments receiving diets containing L. plantarum 108cfu/kg and treatments that received 200 mg/kg lactoferrin in diet had significantly higher growth compared to the control group (p<0.05). But combined use of L. plantarum and lactoferrin did not show any reinforcing effect on feeding and growth parameters. It seems that supplementation of 108cfu of L. plantarum and 200 mg of lactoferrin per kg of diet, alone, is more effective and less expensive way to enhance growth and feeding indices in rainbow trout compared to their combined use.