Effect of a plant-based low-fishmeal diet on digestive physiology in yellowtail Seriola quinqueradiata

Intestinal Transcriptome Analysis Highlights Key Differentially Expressed Genes Involved in Nutrient Metabolism and Digestion in Yellowtail Kingfish (Seriola lalandi) Fed Terrestrial Animal and Plant Proteins

“…This result is entirely consistent with the low and erratic digestibility data presented for CGM in our previous study [32]. These results agree well with the results from a published study [22] on the Japanese yellowtail, S. quinqueradiata, where the expression levels of all the digestive enzyme genes were lower in a diet replacing FM with SBM and CGM. Interestingly, our study found that genes related to endopeptidase inhibitor activity (i.e., itih2, serpinc, serping1) were overexpressed in the intestine of sub-adult YTK fed diets containing BLM and CGM, which suggests that the digestive capacity of the fish was inhibited, consistent with the high protein content in the fecal matter of fish fed these two diets [32].…”

“…The up-regulation of genes encoding proteolytic digestive enzymes (prss1, cela, cpa, cpb) was high in the YTK intestine, indicating that these genes play a crucial role in digestive functions. Prss1 is considered to be the most important proteolytic enzyme, as it plays a key role in hydrolyzing proteins and activating other digestive zymogenes [22,51,52]. Cela, cpa and cpb are involved in protein digestion [51].…”

“…Plant-based ingredients (e.g., soybean, dehulled field pea, wheat and corn gluten) have proved to be useful as partial or even total replacements of FM in both omnivorous and carnivorous aquaculture species [16][17][18][19][20][21]. However, the presence of anti-nutritional factors (ANFs) (e.g., saponins, lectins, protease inhibitors, oligosaccharides) in plant ingredients can cause a number of negative impacts on the digestive physiology, health and metabolism of fish resulting in reduced productivity [22][23][24]. Thus, for fish nutrition research, it is very important to evaluate the potential use of terrestrial animal and plant protein sources in the diet.…”

“…An experiment with European seabass, Dicentrarchus labrax, Reference [31] showed that plant protein sources both activate and suppress the expression of immune related genes. Murashita et al [22] reported that Japanese yellowtail, Seriola quinqueradiata, fed a diet based on soybean meal and CGM displayed faster gastric emptying, lower pH of the gastrointestinal content and suppressed the expression of genes encoding pancreatic digestive enzymes (i.e., trypsin, chymotrypsin and amylase). To our knowledge, there are currently no reports on the use of RNA-sequencing technology to analyze the effect of both terrestrial animal and terrestrial plant protein sources on intestinal gene expression in YTK.…”

Growth of Yellowtail (Seriola quinqueradiata) Fed on a Diet Including Partially or Completely Defatted Black Soldier Fly (Hermetia illucens) Larvae Meal

“…The problem in yellowtail farming is that their diets rely on a high proportion of FM, and little progress has been made in reducing the amount of FM included, and commercial pelleted diet for yellowtail still contains 50-60% FM [17][18][19]. Plant protein, such as soybean meal, has been tried but was found to suppress the secretion of digestive enzymes in yellowtail [20,21]. Therefore, novel animal protein sources that are highly palatable to yellowtail are urgently needed.…”