Modern technologies for crayfish farming: a comparative analysis of industrial and pasture-based methods

This review is devoted to the systematization of modern technologies for the cultivation of freshwater crayfish. The purpose of the work was to generalize an extensive array of scientific data to identify key problems and determine the most effective and promising approaches in their aquaculture. As a result of the research conducted on the basis of the analysis of more than 120 domestic and foreign sources, the following results were obtained. It has been established that the biological features of crayfish, in particular, asynchronous growth and pronounced cannibalism, are the determining factors that form the fundamental differences between their cultivation and the technologies of working with other hydrobionts. Cannibalism is identified as the main limiting factor of planting density and overall productivity. In the course of the analysis, two main directions in crayfish aquaculture were identified and characterized in detail: industrial (RAS, pools) and pasture (natural reservoirs). It was determined that industrial methods make it possible to organize yearround production in controlled conditions, but require significant energy costs, while pasture cultivation is economically beneficial due to the use of a natural fodder base, but its effectiveness critically depends on external abiotic factors, primarily the temperature regime. To solve the key problem of cannibalism, a complex of technological measures was developed and systematized, including the provision of shelter, regular sorting of individuals by size groups, strict standardization of planting density, as well as innovative methods, such as immobilization of claws. A hybrid approach is defined as the most rational and promising production model, which integrates the stages of industrial production and growth of viable planting material in controlled RAS conditions with subsequent growth to marketable condition in natural reservoirs. This strategy makes it possible to level the shortcomings of each of the methods separately and promotes the maximization of economic efficiency and ecological sustainability of the production of valuable hydrobionts.