Health-Promoting Phytobiotic-Based Feed Additive Improves Skin and Gill Proteome Response of Infected Fish

Area of Science:

• Aquatic immunology
• Fish ectoparasite research
• Proteomics in aquaculture

Background:

• Fish skin and gills are crucial immune sites against pathogens.
• Ectoparasites like *Gyrodactylus turnbulli* pose significant threats to fish health.
• Understanding host-parasite interactions is key for disease management.

Purpose of the Study:

• To investigate proteomic changes in guppy skin and gills during *Gyrodactylus turnbulli* infection.
• To assess the impact of a health-promoting additive on fish immune response.
• To correlate protein expression with infection status (susceptible, responding, resistant).

Main Methods:

• Proteomic analysis of skin and gill tissues from infected guppies (*Poecilia reticulata*).
• Comparison of protein expression at 13 and 17 days post-infection.
• Evaluation of fish fed a health-promoting additive versus a control diet.

Main Results:

• Differential protein expression observed based on infection status and dietary supplementation.
• Susceptible fish showed minimal immune response, while resistant fish exhibited up-regulated innate and adaptive immunity.
• Responding fish utilized apoptosis to limit parasite niche, and the additive modulated immune pathways.

Conclusions:

• Fish skin and gill proteomes are significantly affected by ectoparasite burden and dietary supplements.
• Natural immunostimulants show potential for prophylaxis and treatment of aquatic infectious diseases.
• Host immune status dictates the effectiveness of defense mechanisms against ectoparasites.