Immune and proteomic responses to the soybean meal diet in skin and intestine mucus of Atlantic salmon ( Salmo salar L.)

Abstract

The main objective of this study was to increase the knowledge about the mucosal immunity of Salmo salar, using soybean meal‐induced enteritis as a model of inflammation. A control fish meal (FM) and a diet containing 20% soybean meal (SBM) were fed to salmon for seven weeks in seawater. There was no growth difference between groups. However, histology of distal intestine (DI) showed a mild inflammation in the fish fed SBM. Proteomic results revealed differences between the diets. Among the proteins detected uniquely in DI mucus of SBM group, complement C5, Galectin and Glutathione synthetase are involved in innate and adaptive immunity, inflammation, redox signalling and detoxification of xenobiotics in mammals, and similar roles are hypothesized in salmon. Adenylosuccinate synthetase and putative aminopeptidase were uniquely detected in the skin mucus of SBM group. Trypsin enzymatic activity was significantly decreased in the DI of SBM group. Significantly higher production of immunoglobulin M and Mucin‐like protein in DI mucus in SBM group was observed, while an increase in immunoglobulin D and lysozyme but decrease in chymotrypsin was detected in the skin mucus of the same group. We propose mucosal immunoglobulins as diagnostic biomarkers for assessment of novel feed ingredients and aquafeeds.

The Spleen as a Target to Characterize Immunomodulatory Effects of Down-Stream Processed Cyberlindnera jadinii Yeasts in Atlantic Salmon Exposed to a Dietary Soybean Meal Challenge

“…However, high inclusion of plant ingredients such as soybean meal, pea proteins and faba bean in diets for Atlantic salmon (Salmo salar) can have adverse effects on growth performance and fish health (6)(7)(8)(9). In fish, it has already been described that these plant ingredients, due to an imbalanced nutritional composition, content of fiber and antinutritional factors (ANFs) (10,11), can induce significant changes in gutmicrobiome that affect the mucosal immunity, reducing its protective capacity or causing its overreaction, by increasing the secretion of antimicrobial peptides, immunoglobulins and muclike proteins (3,(12)(13)(14). Considering this, solvent extracted soybean meal (SBM) has been used as a dietary challenge to study the impact of alternative ingredients and functional feed components on gut health.…”

The effects of Pediococcus acidilactici MA18/5M on growth performance, gut integrity, and immune response using in vitro and in vivo Pacific salmonid models

“…In the past, inflammation associated with the presence of antinutritional factors in plant ingredients used to feed salmonids (e.g. soybean meal products, soy protein concentrate) has increased the focus in evaluating possible inflammatory processes induced by external products in the fish intestine ( 66 – 68 ). Although it is unknown whether enteritis can be induced by probiotic supplementation, a histopathological analysis is of great importance to determine the safety of P. acidilactici MA18/5M supplementation in Chinook salmon.…”

Microalgae for nutrient recycling from food waste to aquaculture as feed substitute: a promising pathway to eco‐friendly development

“…Secondly, low‐cost biomass enriched with protein is exploited as a feed substitute to partly replace fishmeal. For example, soybean meal and rapeseed meal have been widely used in fish diet to lower the cost of aquaculture 50,51 …”