During the production experiment under the conditions of
ultrasonic treatment at the Soba Fish Hatchery (village of Harp, Yamalo-
Nenets Autonomous District), studies of juvenile muksun were conducted,
which followed the program of compensatory events. The experimental
batch of juveniles was treated by a generator of ultra-weak
pulsed magnetic fields (UWPMF) during the entire period of rearing. The
rearing of juveniles in the closed-circuit water supply unit corresponded
to the accepted standards of the fish hatchery. Fry and fingerlings of the
control and experimental batches were studied using morphometric,
histological and statistical methods. It was found, that the studied morphometric
parameters of the experimental muksun juveniles exceeded
those of the control batch, but were inferior to it in terms of the degree
of mutual correlation. The morphofunctional state of the liver in the juveniles
of the experimental batch had better characteristics, the number
of nucleoli in the nuclei of hepatocytes was increased, and only a few
lipid droplets were present in the basophilic cytoplasm. Significant fatty
inclusions were accumulated in the hepatocytes of the control individuals,
which indicated the initial stages of fatty liver dystrophy. Gonadoand
gametogenesis took place more intensively in the juveniles of the
experimental batch during the entire period of rearing. Summarizing
all data obtained on the parameters of size and weight, morphofunctional
parameters of the liver and generative system of juvenile muksun
in the experiment, it is possible to conclude that the juveniles of the experimental
batch possessed higher adaptation capacities for existence under natural conditions than the control batch.