The effect of simultaneous use of lactic acid and probiotic (Lactobacillus acidophilus) on some parameters of growth, carcass, and blood quality in rainbow trout (Oncorhynchus mykiss)

Growth is a very important factor in economic efficiency of fish breeding farms, so its increasing can improve the fish ponds conditions. For this purpose and for studying the synergistic effects of different amounts of lactic Acid and probiotic lactobacillus acidophilus on growth function, corpse quality and some blood factors of Oncorhynchus mykiss; 540 fishes with average weight of 4:15 ± 2.1 gr in 9 treatments with 3 repetitions were feed by trial food ration including standard trial food ration with and without organic acid and probiotic of 8 weeks. The results showed that the most final weight; weight growth percentage, specific growth, protein efficiency and qualification factor was existed meaning fully in D8 treatment (which feed by ration including probiotic with 109 cfu/g density and 1 % edible lactic acid, D9 treatment (which feed with ration including 109 cfu/g and 1 % edible lactic acid) and specially in D9. Conversion factor in D9, treatment was recorded lower than other treatments (p < 0/05). No significant difference was recorded in fat, protein, ash and humidity amounts between treatments (p > 0/05). The hematocrit level and white blood numbers in D8 and D9 treatments were more than other treatments (p > 0/05) but there was no significant difference in red blood and hemoglobin numbers (p > 0/05).