Article

Investigating the impacts of H(2)O(2) treatment on gills of healthy Atlantic salmon reveals potential changes to mucus production with implications on immune activity

Details

Citation

Fernandez-Senac C, Monaghan SJ, Mascolo D, Baily JL, Betancor M, Chalmers L, Paladini G, Adams A, Fridman S & Bron JE (2022) Investigating the impacts of H(2)O(2) treatment on gills of healthy Atlantic salmon reveals potential changes to mucus production with implications on immune activity. Fish and Shellfish Immunology, 128, pp. 74-81. https://doi.org/10.1016/j.fsi.2022.06.063

Abstract
Current treatment strategies for relevant infectious diseases in Atlantic salmon (Salmo salar L.) include the use of low salinity or freshwater bathing. However, often availability is restricted, and hydrogen peroxide (H2O2) is used as an alternative. The potential impacts of H2O2 on fish mucosal tissues, especially the gills therefore need to be considered. In this study the mucosal and immunological effects of H2O2 treatment on the gills of healthy Atlantic salmon were examined by gene expression (qPCR) and immunohistochemistry (IHC) investigating T-cell, B-cell, and mucin activity. Healthy fish were treated with H2O2 and sampled at different times: 4 h, 24 h and 14 days post-H2O2 treatment (dpt) (total n = 18) to investigate the effect of holding time and H2O2 treatment. Treatment with H2O2 resulted in up-regulation of markers for T-cell activity and anti-inflammatory response and down-regulation of mucin expression in the gills at 14 dpt compared to fish sampled prior to treatment (0h; n = 5 fish). These findings were supported by IHC analysis, which despite being highly variable between samples, showed an increase in the number of CD3+ T cells at 14 dpt in 50% of treated fish compared to pre-treatment fish. The results from this study suggest that H2O2 treatment does not immune compromise healthy Atlantic salmon after 14 dpt (i.e., post-recovery) but modulates gill immune activity and disrupts the mucus covering of the gills. However, further studies are required to determine whether the effects observed are related to H2O2 treatment in isolation or other variables such as holding time or environmental factors.

Journal
Fish and Shellfish Immunology: Volume 128

StatusPublished
FundersEuropean Commission (Horizon 2020)
Publication date30/09/2022
Publication date online31/07/2022
Date accepted by journal27/06/2022
URLhttp://hdl.handle.net/1893/34543
ISSN1050-4648

People (5)

People

Dr Monica Betancor
Dr Monica Betancor

Associate Professor, Institute of Aquaculture

Professor James Bron
Professor James Bron

Professor, Institute of Aquaculture

Miss Carolina Fernandez
Miss Carolina Fernandez

PhD Researcher, Institute of Aquaculture

Dr Sophie Fridman
Dr Sophie Fridman

Post Doctoral Research Fellow, Institute of Aquaculture

Dr Sean Monaghan
Dr Sean Monaghan

Senior Lecturer, Institute of Aquaculture

Projects (1)