Replacement of fish meal with soybean meal in diets for pink shrimp (Farfantepenaeus paulensis)
Author: Marcos Paulo Abe (Currículo Lattes)
Supervision: Dr Ronaldo Cavalli
Abstract
This study aimed to evaluate the replacement of fish meal with soybean meal in practical diets for the pink shrimp, Farfantepenaeus paulensis. Six iso-protein and iso-energy diets, containing different proportions of fish meal and soybean meal, were provided to post-larvae of this shrimp for 28 days. The levels of fish meal substitution for soybean meal were 0% (control), 12%, 24%, 36%, 48% and 60%, with the experimental diets being named according to the respective levels of substitution. A water recirculation system with 24 plastic boxes containing 40 liters of sea water and a 200 liter biological filter was used. One hundred post-larvae (PL10) of shrimp, with an initial weight of 1.22 mg (± 0.44) and a total length of 7.77 mm (± 0.93),were randomly assigned to each of the experimental units. The means (± standard deviation) of temperature, salinity and pH during the experimental period were 27.6ºC (± 0.9), 34.2 (± 1.0) and 8.09 (± 0.05), respectively, while that of dissolved oxygen was 7.30 mg / L (± 0.37). The mean concentrations of total ammonia and nitrite were 0.05 mg / L N-AT (± 0.02) and 0.03 mg / L N-NO2- (± 0.05), and at the end of the experiment , the nitrate reached 2.27 mg / L N-NO3 -. The 60% fish meal replacement diet resulted in the greatest weight gain (p <0.05). The control diet resulted in the lowest growth (p <0.05). Similarly, TBI was also higher for the 60% diet and lower for the 0% diet (p <0.05). The final weight ranged from 20.84 to 27.37 mg and the specific growth rate (TBI) was between 9.1 and 10.7% / day.The survival rate of the different treatments ranged from 70 to 80%, with no significant differences being detected (p> 0.05). According to the conditions of the present study, we can conclude that the replacement of up to 60% of fishmeal by soy meal in practical diets results in a higher specific growth rate and, consequently, in the final weight of F .paulensis pink shrimp, without change survival.