Nutraceuticals for smart aquaculture: from modes of action to practical application

Aquaculture has a crucial and rapidly increasing role in global food security. Thanks to the diversification in the culture systems (i.e. farming in open ponds and cages to land-based RAS and bioflocs) as well as to the intensification in the farming practices. These diversifications and intensification, however, pose two major concerns before us: i) stress and infectious disease outbreaks, which have a negative impact on the growth, health, and welfare of aquaculture animals, ii) limitation in the availability of nutraceuticals to address issues related to stress, growth, and disease. In Sweden and elsewhere, a wide variety of ingredients from sustainable and less competitive natural sources are being produced, which can be potentially used as nutraceuticals.

The aim is to address specific issues, thus bringing solutions to recurrent problems in aquaculture production cycles, that include poor growth and health, disease outbreaks, and poor flesh quality of the farmed products.

Testing a huge collection of ingredients for their nutraceutical activities in several farmed animals can be labor-intensive, time-consuming, and most importantly expensive. My research plan includes using Artemia as a biological organism to screen these additives for their whole range of nutraceutical (e.g. growth promotion, immunes-stimulation, antimicrobial, prebiotic, probiotic) properties. These live-animal screening

studies will assist us in selecting a few candidate nutraceuticals that could be further used either alone or in combination with other available functional ingredients in the development of next-generation functional feed. Uncovering the mechanistic bases of the function of each of these nutraceuticals is important because this knowledge is key for a feed company to customize the functional feed to meet the needs of the fish farmer and also to foster their registration as feed additives in a registration agency.

A state-of-the-art Artemia testing facility has been established at SLU-HUV and is currently up and running. In Sweden, rainbow trout and Arctic char are the two major farmed coldwater fishes. Farming of tropical species like Tilapia, shrimps are expected to increase in the coming years, partly due to the ongoing establishment of land-based farms (RAS, Biofloc). In my lecture, I will first discuss the increasing need for the identification and use of nutraceuticals for sustainable aquaculture, We will then discuss, based on the published data from my and other research groups, the special advantages of Artemia as a biological model for aquaculture nutraceutical research.