Insect meal is gaining increased attention in aquafeed formulations due to high protein content and an essential amino acid profile similar to that of fishmeal. To investigate insect meal in feed for European perch Perca fluviatilis, a promising candidate for European intensive culture, we replaced standard fishmeal with partially defatted black soldier fly Hermetia illucens larva meal at rates of 0%, 20%, 40% and 60% (groups CON, H20, H40 and H60, respectively) and compared growth performance, somatic indices, hematological parameters, whole-body proximate composition and occurrence of spleen lipidosis. In addition, we assessed the economic and environmental sustainability of the tested feeds by calculating economic conversion ratio (ECR) and economic profit index (EPI). The tested groups did not differ in survival rate. Significant differences were documented in final body weight and specific growth rate, with the highest values in CON, H20 and H40. The proximate composition of fish whole-body at the end of the experiment did not differ in dry matter, crude protein or ether extract, while organic matter, ash and gross energy composition showed significant differences. The fatty acid content and n-3/n-6 ratio showed a decreasing trend with increasing H. illucens larva meal inclusion. No differences were found in hematological parameters among tested groups. The H. illucens larva meal inclusion significantly affected ECR and EPI, even at 20% inclusion level the cost of diets did not differ from the control fish meal based diet. Results suggested that 40% inclusion of H. illucens larva meal can be used successfully in standard diets for perch.

Water from wastewater treatment plants contains concentrations of pharmaceutically active compounds as high as micrograms per liter, which can adversely affect fish health and behavior, and contaminate the food chain. Here, we tested the ability of the common carp hepatic S9 fraction to produce the main metabolites from citalopram, metoprolol, sertraline, and venlafaxine. Metabolism in fish S9 fractions was compared to that in sheep. The metabolism of citalopram was further studied in fish. Our results suggest a large difference in the rate of metabolites formation between fish and sheep. Fish hepatic S9 fractions do not show an ability to form metabolites from venlafaxine, which was also the case for sheep. Citalopram, metoprolol, and sertraline were metabolized by both fish and sheep S9. Citalopram showed concentration-dependent N-desmethylcitalopram formation with V_max = 1781 pmol/min/mg and K_m = 29.7 μM. The presence of ellipticine, a specific CYP1A inhibitor, in the incubations reduced the formation of N-desmethylcitalopram by 30–100% depending on the applied concentration. These findings suggest that CYP1A is the major enzyme contributing to the formation of N-desmethylcitalopram. In summary, the results from the present in vitro study suggest that common carp can form the major metabolites of citalopram, metoprolol, and sertraline.

Ecosystem and aquaculture in estuary areas are sensitive to climate change and severe climatic events. In this study, three environmental monitoring events were carried out on a 1800-ha clam culture area in Giao Thuy district, Nam Dinh province, Vietnam. The first monitoring was carried out in fair weather. The second and 3rd monitorings were conducted two days after the Ma On and Noru storms, respectively. The variation of water and sediment physicochemical variables, zoobenthos and plankton composition and density, and clam pathogen were investigated at five locations. In addition, long-term variations of temperature, rainfall, and sunshine duration in the area were investigated. The results illustrated the increased temperature, rainfall, and sunshine duration tendency. The clam-cultured species and activities had substantially changed. Ma On and Noru negatively impacted water quality by decreasing the water quality index by 39% and 30%, respectively. Storms decreased water salinity, alkalinity, and sediment’s phosphorus, iron, lead. However, they increased water’s nitrite, phosphorus, total suspended solid, phytoplankton, zooplankton density, and sediment’s total nitrogen, cadimium. The total Vibrio spp. density in clam highly fluctuated between the two storm events. The effect of storm varied according to site location. Shallow and domestic wastewater adjacent sites suffered high risks of extreme temperature, salinity variation, and organic pollution.