Desempenho gonadal de adultos do Penaeus vannamei alimentados com dietas semi-umidas suplementadas com óleo de krill frente a reduções de alimento fresco

Abstract

The maturation of shrimp occurs through hormonal, environmental and nutritional manipulation. The main form used for the maturation of broodstock in the commercial sector is nutritional, inducing the ovarian development of females. New feeding alternatives are being sought to eliminate the use of fresh food, which entails a range of problems, such as biosecurity risk, cross-contamination, low fresh food stock and quality instability. The study aimed to evaluate the potential for reduction of fresh food in the feeding of P. vannamei breeders along with krill oil supplementation. The research was carried out at the Laboratory of Nutrition of Aquatic Organisms (LANOA) of the Center for Coastal Environmental Studies (CEAC) of the Institute of Marine Sciences (Labomar/UFC). Five circular tanks of suspended PVC plastic canvas with galvanized carbon steel structure with 6.37m³ of total volume (2.60 m diameter x 1.20 m depth = 5.31 m² bottom area) kept outdoors. A total of 135 shrimps with CP of 21.47 ± 1.89g were obtained and stored at a density of 5.1 shrimps/m² (27 shrimps per tank) in the experimental tanks. The animals were cultivated for a period of 23 days, being fed with commercial feed containing 38% CP. After 76 days of cultivation, the average survival of shrimp reached 81.7 ± 12.1%. Shrimp on an 80-20-KO diet were the only ones to achieve 100% survival. The highest weekly growth was observed for the KRL diet (1.80g), followed by 80-20-KO (1.33g) and 80-20-CTL (1.15g). Through the present study, it is concluded that the experimental conditions, where the shrimps were fed under different combinations of fresh food (squid) and commercial diet and (or) laboratory, with or without krill oil supplementation, may present gonadal development.