Dietary Butyrate Helps to Restore the Intestinal Status of a Marine Teleost (Sparus aurata) Fed Extreme Diets Low in Fish Meal and Fish Oil

Abstract

There is a constant need to find feed additives that improve health and nutrition of farmed fish and lessen the intestinal inflammation induced by plant-based ingredients. The objective of this study was to evaluate the effects of adding an organic acid salt to alleviate some of the detrimental effects of extreme plant-ingredient substitution of fish meal (FM) and fish oil (FO) in gilthead sea bream diet. Three experiments were conducted. In a first trial (T1), the best dose (0.4%) of sodium butyrate (BP-70 ®NOREL) was chosen after a short (9-weeks) feeding period. In a second longer trial (T2) (8 months), four diets were used: a control diet containing 25% FM (T2-D1) and three experimental diets containing 5% FM (T2-D2, T2-D3, T2-D4). FO was the only added oil in D1, while a blend of plant oils replaced 58% and 84% of FO in T2-D2, and T2-D3 and T2-D4, respectively. The latter was supplemented with 0.4% BP-70. In a third trial (T3), two groups of fish were fed for 12 and 38 months with D1, D3 and D4 diets of T2. The effects of dietary changes were studied using histochemical, immunohistochemical, molecular and electrophysiological tools. The extreme diet (T2-D3) modified significantly the transcriptomic profile, especially at the anterior intestine, up-regulating the expression of inflammatory markers, in coincidence with a higher presence of granulocytes and lymphocytes in the submucosa, and changing genes involved in antioxidant defences, epithelial permeability and mucus production. Trans-epithelial electrical resistance (Rt) was also decreased (T3-D3). Most of these modifications were returned to control values with the addition of BP-70. None of the experimental diets modified the staining pattern of PCNA, FABP2 or ALPI. These results further confirm the potential of this additive to improve or reverse the detrimental effects of extreme fish diet formulations.

Progress and perspectives of short‐chain fatty acids in aquaculture

“…), while the potential beneficial effects of an SB (BP‐70 ® Norel) supplemented diet on the growth performance of gilthead sea bream ( S. aurata ) have been observed (Estensoro et al . ). Although both viscerosomatic and hepatosomatic indexes were not significantly altered, the gut index was significantly higher in fish fed on SB‐supplemented diet (0.8% BP‐70) compared to the other groups, the SB (0.4%) resulted in an increase in the plasma glucose and cortisol levels in gilthead sea bream (Estensoro et al .…”

“…Although both viscerosomatic and hepatosomatic indexes were not significantly altered, the gut index was significantly higher in fish fed on SB‐supplemented diet (0.8% BP‐70) compared to the other groups, the SB (0.4%) resulted in an increase in the plasma glucose and cortisol levels in gilthead sea bream (Estensoro et al . ). Recently, Tian et al .…”

“…A diet supplemented with 0.8% butyrate increased the abundance of mucosal folding, infiltration of lymphocytes through the epithelial base, number of granulocytes in the submucosa along with the intestine and accumulation of glycogen in hepatocytes (Estensoro et al . ).…”

“…In gilthead sea bream, Estensoro et al . () observed that the two genes, proliferating cell nuclear antigen (PCNA) and intestinal FA‐binding protein (FABP2), were expressed in the intestinal tract; however, only PCNA had significantly low expression in the fish fed on 0.8% butyrate‐supplemented diet. Similarly, administration of butyrate (0.8% in the diet) for 10 weeks decreased the cumulative mortality of gilthead sea bream after challenge with Photobacterium damselae subsp.…”

Current Advances in Functional Genomics in Aquaculture

“…Interestingly, reducing arginine levels to 0.5% in the diet supplements signiicantly increased respiratory burst to levels comparable with control ish. In another study, Estensoro et al [113] showed that butyrate (BP-70 ® NOREL) helped to restore the intestinal status of marine gilthead sea bream (Sparus aurata) fed extremely low diets of ish meal (FM) and ish oil (FO). They observed that extremely low FO and FM diet levels signiicantly altered the transcriptomic proiles linked to nutrient absorption in the AI and increased expression of inlammatory, antioxidant, permeability and mucus production genes that coincided with increased granulocyte and lymphocyte presence in the PI submucosa.…”