Pacific white shrimp, red drum and tilapia integrated in a biofloc system: use of tilapia as a consumer of total suspended solids.
Poersch, L., Brunson, J., Gaona, CAP, Stokes, A., Richardson, J., Pitts, K. and Leffler, J.
Suspended solids present a challenge in the management of the biofloc production system as they can become excessive and require removal/disposal. Poersch et al added Nile tilapia, Oreochromis niloticus, as biological suspended solids controllers in an integrated red drum farming biofloc technology (BFT) system, Sciaenops ocellatus, and Pacific white shrimp, Litopenaeus vannamei. Although all system performance metrics remained stable, the presence of tilapia in the system significantly reduced particulates in the system. Appropriate co-culture of tilapia can control suspended solids when integrated with red drum/marine shrimp culture with BFT in an integrated multi-trophic system.
Assessment of bivalve carrying capacities and stocking densities in aquaculture areas of Jiaozhou Bay, China using ecological modeling and food balance.
Liu, X., Zhang, M., Wang, Z., and Wang, B.
Bivalve aquaculture and the cultivation of other extractive organisms are increasingly popular globally as sustainable marine food production. With increasing popularity and cultural densities, it is imperative that the carrying capacities of ecosystems are understood and respected. In their latest study, Liu et al. adopting an ecological modeling approach for bivalve aquaculture in Jiaozhou Bay, China. They are able to show a clear seasonality of carrying capacities for all species of bivalves studied and to link a reduced carrying capacity to an increase in temperatures. Their results indicate a clear link between primary production and carrying capacity for all species. The authors provide recommendations for reducing stocking densities for key species, as well as a new and appropriate modeling method that others can apply.
A method for minimizing the area of low water flow velocity in a bottom center drain circular aquaculture tank.
Sin, MG, An, CH, Cha, SJ, Kim, MJ, Kim, HN.
Low water velocities, poor mixing and the deposition of solids can lead to suboptimal conditions in circular aquaculture tanks. Optimization of inflows and reservoir design was frequently discussed. However, Sin et al. apply mathematical modeling using computed fluid dynamics to reservoir design and water inlets. Their goal is to suppress low-velocity zones and optimize water quality in land-based reservoir systems. They validate their modeling results in real reservoir systems. By using an adjustable vertical nozzle pipe with multiple water outlets along the length of the pipe, they are able to achieve valuable reductions in low velocity areas of tanks and vast mixing improvements. The results provide practical methods for improving water quality and animal health in land-based livestock systems.
). In vitro efficacy of quillaja soapwort extracts on the infectious stage of the ectoparasite Caligus rogercresseyi.
Cañon Jones, HA, Schlotterbeck Suarez, T., Castillo-Ruiz, M., Cortes Gonzalez, H., Asencio, G., Latuz, S. and San Martín, R.
Triterpinoid saponins are natural chemicals that may be a promising alternative to synthetic pest control treatments. In their recent study, Cañon Jones et al. tested various concentrations of quillaja soapwort larval extract Caligus rogercresseyi, which is responsible for sea lice infestations in the southern hemisphere. Concentrations of 500 ppm of extract were sufficient to kill or stun infective larvae, with efficacy increasing with exposure periods. With high levels of efficiency and negligible environmental concerns associated with its use, quillaja soapwort The extract can be a valuable addition to the tools available to aquaculture producers battling the significant economic and animal welfare challenges created by sea lice infestations. Future studies should determine the effects of the extract on salmonids and appropriate treatment methods.