Integrating Litopenaeus vannamei into Dicentrarchus labrax hypersaline earthen ponds improves productivity and farm profitability: evaluating shrimp performance and economic viability under the effect of bile acid supplementation
摘要
European seabass Dicentrarchus labrax producers face great difficulties because the production cycle lasts about two years. This study aimed to integrate whiteleg shrimp Litopenaeus vannamei (production cycle lasts 4–5 months) into seabass ponds to increase profitability by generating multiple shrimp production cycles. Eight hundred and ten healthy L. vannamei (mean weight = 1.81 ± 0.003 g) were distributed into 18 net cages (each 500 L‒water, containing 45 juveniles) installed in an earthen seabass pond. Shrimp were fed a basal diet (BD) containing 40% crude protein with two lipid (L) levels and three bile acid (BAs) levels per kg/diet to run six groups (factorial design) in triplicate: L7BA0 (7.1% lipids, 0g BAs; Diet F1), L7BA0.25 (7.1% lipids, 0.25g BAs; Diet F2), L7BA0.50 (7.1% lipids, 0.50g BAs; Diet F3), L8BA0 (8.3% lipids, 0g BAs; Diet F4), L8BA0.25 (8.3% lipids, 0.25g BAs; Diet F5), and L8BA0.50 (8.3% lipids, 0.50g BAs; Diet F6). Shrimp were raised using a salinity of ≈ 45 ppt with a daily feeding rate of 5% for 60 days. No differences were recorded in water quality parameters (dissolved oxygen, ammonia, and salinity) between shrimp groups and the seabass pond. Shrimp groups fed BAs-supplemented diets presented increased (p < 0.05) survival rates (L7BA0.25, L7BA0.50, and L8BA0.50) and final weights (L7BA0.25), with lower FCR (L7BA0.25, L7BA0.50, and L8BA0.25) and cortisol with improved immune markers, hemolymph health, digestive enzymes, lipid profile, antioxidants, growth hormone, and β-actin. The L7BA0.25 diet is recommended when incorporating L. vannamei into hypersaline seabass ponds to maximize farm profitability and support seabass aquaculture sustainability.