Rationale for the use of humats in aquaculture (a review)

Abstract

Purpose. To prepare a justification for the use of sodium and potassium salts of humic and fulvic acids (humates) as substances with biologically active properties in fish feeds based on the analysis of sources of scientific and technical information and own experimental materials, Findings. A complex general characteristic of humic substances was provided, the mechanism of biologically active action of humates on living organisms was described. Examples of the use of humates in crop production, medicine, animal husbandry and aquaculture were given. The results of our own studies on the use of humates as a feed additive for valuable objects of aquaculture were presented. Prospects for the inclusion of micro-additives of sodium and potassium humates in the composition of fish feed in order to increase fish survival and digestibility of feed were outlined. Originality. To date, the introduction of humates into fish feed as micronutrients was experimental. The analysis of scientific sources and materials of own studies gave the basis for the conclusion about the need of complex detailed studying of mechanisms of effects of humates on fish. In particular, it is of interest to study the protective properties of humates from the accumulation of heavy metals in the body of fish for the use of micronutrients of these substances in fish feeds. Practical value. The use of humate feed additives in aquaculture will help to solve such urgent problems as the prevention of excessive losses of biological material of cultivated objects, reduction of feed costs, improvement of consumer characteristics of food products. Humates, as substances of natural origin with protective and immunomodulatory action, can become substitutes for some synthetic therapeutic and prophylactic drugs. Key words: aquaculture, humates, compound feed, feed additive, growth rate, survival, feed assimilation.