Inclusão de macrófitas aquáticas na ração de carpa capim (Ctenopharyngodon idella)

Abstract

The macrophytes present a large adaptability and ecological amplitude. This fact enables the same species colonizes over different types of environments. At fish farming, aquatic macrophytes can be harnessed as water fertilizers, providing an increase of organisms that participate in the food chain of fish or as an alternative source of protein and fiber. The greater efficiency of this food source is achieved in herbivorous fish nutrition or omnivores such as carp and tilapia. In the present study, it was evaluated the production data of juveniles grass carp (Ctenopharyngodon idella) feed with a diet supplemented with aquatic macrophytes flour as an alternative for fiber replacement to green fodder. The experiment lasted 60 days and the production data were obtained from biometrics fortnightly. The experimental design was completely randomized with four treatments and three repetitions, with ten units of juvenile grass carp in each tank. It were used 12 tanks with capacity of 40 L in a closed circulation system and recirculation of water. The average weight was 40.68 g and the initial average length was 73.46 mm. The treatments were: T1: only feed; T2: feed more elephant grass; T3: feed prepared with 20% macrophyte Ludwigia spp flour and T4: feed prepared with 20% macrophyte Potamogentun berteroanus flour. As for the weight gain, total length and standard length of variables there was no significant difference between the treatments T1, T3 and T4, but the T2 showed a significant increase compared to the other treatments