Analysis of the age dynamics of morphological parameters of rainbow trout blood in aquaculture conditions

Rainbow  trout  (Parasalmo  mykiss)  is  a promising  type  of  aquaculture  with  one  of the  largest  production  potentials  in  Russia. The  Republic  of  Karelia  currently  holds  a leading position in cage trout farming, supplying more than 80% of commercial trout produced  in  the  Russian  Federation  to  the domestic  market.  Increasing  the  output  of aquaculture products is an important condition  for  supporting  Russia's  food  security and  ensuring  the  socio-economic  development of the regions. Given the rate of spread of  diseases  in  trout,  the  rapid  change  of phases  of  the  immune  response  in  fish,  as well as the location of farms in sparsely populated remote areas, research remains particularly  relevant  on  the  search  for  sensitive molecular  methods  of  rapid  diagnosis  that identify the pathogen in the early stages of the  infectious  process  to  develop  rational treatment  and  prevention  tactics.  The  purpose of the presented study was to monitor the condition of rainbow trout in ontogenesis based on hematological studies. During the study, significant (P<0.05) differences were noted in the number of red blood cells and the total number of white blood cells (TLC), depending on the sex of the fish. In addition, clearly  distinguishable  morphometric  features  were  also  seen  among  erythrocytes, leukocytes  (lymphocytes,  neutrophils  and monocytes)  and  platelets.  Thus,  during  the monitoring of the physiological state of rainbow trout in aquaculture conditions, it was found  that  the  condition  of  the  fish  body worsens with age, which affects the morphological parameters of the blood. The hemoglobin content varied widely. A decrease in its  concentration  indicates  acute  blood  loss and hemolytic anemia. The results obtained are  the  basis  for  the  development  of  new promising natural adaptogens that normalize the physiological state of fish and ensure the production of biosafety trout products.