Substituição integral da farinha de salmão por farinha de vísceras de aves Low-Ash, em rações para juvenis do camarão Litopenaeus vannamei

Abstract

The Pacific white shrimp, Litopenaeus vannamei is the most commercially farmed crustacean in the world. In recent years, the use of fishmeal in industrially-manufactured feeds for aquatic organisms has become an obstacle given the limitations in its supply and price. Consequently, research on the potential of alternative proteins for use in diets for shrimp and other aquatic organisms has grown. The present study aimed at evaluating the growth performance (1st stage) and the feed preference (2nd stage) of juveniles of L. vannamei fed diets with progressive replacement (0, 25, 50, 75 and 100%) of a salmon meal (SM) containing 64.44% crude protein (CP, as-is) and 8.71% ether extract (EE) for a low-ash poultry meal (PM) with 69.79% CP and 13.66% EE. diets were formulated to be isoproteic, isocaloric and isoaminoacidic, with dietary inclusions (% of the diet, as-is) of SM and PM of 12.00 and 0 (diet 12-0), 9.00 and 2.22 (9-2), 6.00 and 4.90 (6-5), 3.00 and 7.59 (3-8) and 0 and 10.27%, respectively. In the 1st stage, shrimp of 0.80 ± 0.04 g stocked in 28 indoor tanks of 0.5 m3 were reared for 72 days under 123 animals/m2. Water salinity, temperature and pH reached an average of 30 ± 5.2 g/L, 27.8 ± 0.7oC and 7.9 ± 0.3, respectively. In the 2nd stage, shrimp of 8.07 ± 4.5 g were stocked under 70 animals/m2 and grown for 14 days in 22 tanks of 0.5 m3

. Feed preference was determined based on the apparent feed intake (AFI) by simultaneously delivering two different diets in excess in each tank, twice a day in two feeding trays. At harvest, no statistically significant difference was detected in the final shrimp survival (92.8 ± 5.6%), gained yield (866 ± 86 g/m2

), AFI (13.0 ± 0.8 g/shrimp) and weekly growth (0.76 ± 0.07 g). However, the 12-0 diet registered a higher FCR (1.98 ± 0.16) compared to diets 9-2 (1.75 ± 0.09) and 6-5 (1.77 ± 0.09). The highest final shrimp body weight was achieved with diets 3-8 (8.78 ± 0.24 g) and 6-5 (8.74 ± 0.26 g), followed by diets 0-10 (8.47 ± 0, 31 g) and 9-2 (8.40 ± 0.37 g). In conclusion, the PM replaces up to 75% the SM in practical diets for the grow-out of juveniles of L. vannamei, without detrimental effects to its growth performance. It is possible to reduce the dietary inclusion of SM from 12 to 3% when using 8% PM. The complete substitution of SM for PM does not cause any deleterious effects on the feed preference of L. vannamei.