Do selenium nanoparticles in fish food cause subtle alterations in behavior of fish: effect of particles size and concentration?
- 2018 - 2019
- AQUAEXCEL2020, a Horizon 2020 research infrastructure project
Selenium engineered nanoparticles (Se ENPs) holds great promises to decrease fish meal and fish oil applications in aquaculture. Due to unknown toxicity to fish, application of Se ENPS as nutritional supplements in fish food is very limited. For example, they may have different mechanisms of toxicity to organisms in comparison to their soluble counterparts. The ambition is to provide data and novel approaches to support application of Se ENPs as nutritional supplements in fish diet at safe concentrations and size in order to decrease or substitute fish meal and fish oil applications.
Aquaculture is a rapidly growing world-wide industry with a requirement for sustainable and novel feed ingredients to decrease or substitute fish meal and fish oil applications. ENPs can increase the proportion of fish food nutrients that pass across the gut tissue into the fish, rather than passing directly through the fish digestive system unused. This accelerates the assimilation process of the nutrients into the fish.
The use of Se ENPs as nutritional supplements in fish diet is however limited due to their unknown toxicity profile, especially since it is realized that Se ENPs are designed to have an enhanced bioavailability. Se ENPs, which act on the basis of the nano-specific properties of the particles such as small size and large surface area, may induce a different mode of biodistribution in comparison to dissolved Se. Thus, it is likely that Se ENPs reach targets inside fish that cannot be reached by dissolved Se Fish behavior is a sensitive indicator of low concentrations of certain contaminants, often becoming evident at concentrations at which other sublethal effects are not visible yet. Behavioral alteration can cause ‘ecological death’, indicating that even if fish are not overtly harmed by a contaminant they may be unable to function in an ecological context if their normal behavior is altered.
There are many methods developed to investigate swimming behavior of fish. Mostly, fish behavior investigations are based on analyses by expert observations and/or monitoring tools e.g. video recording of the behavior and subsequent offline analysis of video records. These approaches have some disadvantages. For example, they are very time consuming and subjective and they explore just a limited amount of the information contained in the data.
Herein, the ambition is to provide data and novel approaches to support application of Se ENPs as nutritional supplements in fish diet at safe concentrations and size in order to decrease or substitute fish meal and fish oil applications.