Thus It Is Necessary To Solve A Number

Thus it is necessary to solve a number of problems, namely: to study features of reproduction, development, a food, the relation to external factors of environment, and also to estimate a specific variety and their numerical structure. The practical importance of work consists in the following: The lowest Crustacea long since are a valuable forage for animals, and Daphnia magna - an original biofiltration organism with which help it is possible to carry out clearing of cattle-breeding drains; dried are used for feeding of aquarian fishes, serve as the excellent additive in mixed fodders of any appointment. The first experiences spent on the lowest Crustacea concern the end of 19 centuries. "Russian method" N.A.Depp (1889) was the most developed at that time. The big development works on Cladocera have received Derzhavin, 1938, 1947; Zarinsky, 1939; , 1949, 1950, etc. From all lowest Crustacea the most perspective group for is group Cladocera. Such kinds concern it, as Polyphemus pediculus Zinne, Sida crystallina, Daphniz magna and many other things.