Plasma glucose level variation to immunization in rainbow trout with gamma irradiated Ichthyophthirius multifiliis trophonts: relationship

The Ichthyophthirius multifiliis is one of the most important protozoan pathogens of farmed and wild fish populations. The vaccination against I. multifiliis can be considered as an alternative to chemical treatments. At the current study, fifty rainbow trout (40 - 50 g) were infected with I. multifiliis via live trophonts, trophonts were collected with 200-mesh sieve. After collection, dose of gamma ray (170 Gray) was used to irradiate parasite. Then, commercial Ergosan was suspended in sterile 0.15 M (pH 7.2) and sonicated. Remaining powder was irradiated by gamma irradiator (30 KGray). The alginate nanoparticle encapsulated irradiated parasite was achieved by the addition of PBS (1 mL) to the alginate nanaoparticle solution (4 mL) plus irradiated trophonts (37˚C, pH 7.5). Fish were distributed equally into 5 groups (60 fish/aquarium). A significant increase in plasma glucose level was shown in rainbow trout challenged with live trophonts at 7 days after challenge (P < 0.05). The serum glucose levels increase during stress; decrease of glucose can be linked to depletion of reserve energy. Additionally, activating the immune system is energetically costly. This research would give key clues to the understanding of plasma glucose level variation under stress in immunized rainbow trout. Further in-depth studies should provide more in-sights into fish immunization and the corresponding ways to reduce stress probable harm.

Keywords:

Glucose level , gamma irradiation , Ichthyophthirius multifiliis , rainbow trout