Majallah-i ̒Ilmī-i Shīlāt-i Īrān (Jan 2015)
Effect of different levels of Azolla meal on growth performance and digestibility of common Carp (Cyprinus carpio)
Abstract
In this study, the effects of different dietary levels of Azolla meal were investigated on growth performance and digestibility of common carp (Cyprinus carpio) fingerlings during 60 days. Five experimental diets approximately iso-protein (30%) and iso- lipidic (10%), were formulated with different levels of Azolla meal consisting of 0, 15, 25, 35 and 45%, respectively. In each experimental treatment, triplicate groups of common Carp fingerlings (16.5± 0.2 g) were used in a completely randomized design. Twenty fish were assigned to each experimental unit and stocked in 300 L tank. The results showed that the use of Azolla meal up to 15% had no negative effect on growth performance. The growth of fish was reduced significantly with increasing Azolla meal level of more than 15% of diet. Based on results, the apparent digestibility coefficients (ADC) of dry matter decreased with increasing Azolla meal in diets. The highest ADC of protein was observed in control treatment. However, no significant difference was observed between the treatment 2 (diet with 15% Azolla meal) and control (without Azolla meal) for ADC of protein. In general, results of the present study showed that Azoll meal can be used up to 15% in Cyprinus carpio diet.
