Growth performance, intestinal morphology, blood biomarkers, and immune response of Thinlip Grey Mullet (Liza ramada) fed dietary laminarin supplement

Abstract

Laminarin is a source of immunostimulants and antioxidative biomolecules involved in supporting the performance and health of aquatic animals. Hence, this study investigated the growth performance, intestinal morphology, blood biomarkers, and immune response of Thinlip Grey Mullet (Liza ramada) fed dietary laminarin. For 60 days, mullets were fed diets supplemented with laminarin at 0, 200, 400, 600, and 800 mg kg−1, then the growth performance was evaluated, and samples were collected. The FBW, WG, SGR, PER, and carcass lipid content were markedly increased, while the FCR was significantly lowered by dietary 600 and 800 mg kg−1. Further, the lipase and protease activities were significantly higher in mullets fed laminarin at 600 mg kg−1 than those fed 0, 200, 400, and 800 mg kg−1. The intestinal histopathological evaluation revealed that all layers of the intestinal villi and the intestinal wall appeared intact without any deteriorating changes. The intestinal mucosal lining of anterior and middle segments showed improved morphological appearance with increased goblet cells in the intestinal villi associated with increased supplemented laminarin level. The total protein, globulin, and total cholesterol were markedly higher in fish fed 400 and 600 mg kg−1 laminarin than those fed 0, 200, and 800 mg kg−1. Furthermore, the lysozyme, catalase, and glutathione peroxidase activities were higher in mullets fed laminarin at 600 mg kg−1 than those fed a laminarin-free diet. The superoxide dismutase was higher in fish fed 200, 400, and 600 mg kg−1than those fed 0 and 800 mg kg−1. On the other hand, the malondialdehyde activity was markedly decreased by 400 and 600 mg kg−1 of dietary laminarin. Overall, dietary laminarin is required at 338–761 mg kg−1 to reveal the best growth performance, intestinal morphology, blood biomarkers, antioxidative, and immune response in mullets.

Growth performance, digestive capacity and intestinal health of juvenile spotted seabass (Lateolabrax maculatus) fed dietary laminarin supplement

“…In this study, the supplementation of 0.8% laminarin significantly increased the intestinal amylase and trypsin activities of spotted seabass. The results are comparable with those of Abdel-Mawla et al, who stated found that dietary supplementation of 338-761 mg kg -1 laminarin enhanced the digestive enzyme activity of Liza ramada (Abdel-Mawla et al, 2023). At the same time, the results of this study were consistent with the results of growth performance, indicating that an appropriate amount of laminarin can enhance digestive enzyme secretion and improve nutrient digestion and absorption in spotted seabass, thereby promoting their growth.…”

“…There are few studies on aquatic animals. Abdel-Mawla et al (2023) found that dietary laminarin can improve intestinal villi morphology and increase the number of goblet cells in Liza ramada. This is The data presented are expressed as mean ± standard deviation (n=3).…”

“…Laminarin not only exhibits various pharmacological activities such as anti-oxidation, anti-tumor, anticoagulation, anti-cancer, immune regulation, anti-obesity, antidiabetes, anti-inflammatory and regulation of intestinal flora, but also has the characteristics of biodegradation, good biocompatibility and natural low toxicity (Vidhya Hindu et al, 2019;Karuppusamy et al, 2022). Studies have demonstrated that dietary laminarin can significantly improve the growth performance and immune capacity of grouper (Epinephelus coioides) and rainbow trout (Oncorhynchus mykiss) (Morales-Lange et al, 2015;Abdel-Mawla et al, 2023). Likewise, the addition of 4 g kg -1 and 8 g kg -1 laminarin augmented antioxidant enzyme and digestive enzyme activities and promoted the growth of Ictalurus punctatu (Jiang et al, 2021).…”

“…In aquatic animals, Wu et al found that dietary supplementation of 5 g Kg -1 laminarin significantly increased the beneficial intestinal bacteria Bacteroide, Comamonas and Mycoplasma abundance in juvenile largemouth bass (Wu et al, 2023). Abdel-Mawla et al (2023) reported that the addition of laminarin could improve the intestinal morphology and increase the number of intestinal goblet cells of Thinlip Grey Mullet (Liza ramada). These studies suggest that laminaria polysaccharide holds promising potential for enhancing the growth of animals and promoting intestinal health maintenance.…”

Seaweed and Seaweed-Based Functional Metabolites as Potential Modulators of Growth, Immune and Antioxidant Responses, and Gut Microbiota in Fish

“…These epithelial cells assist in the production of IgA through the activation of T cells and B cells that play a defensive role against various antigens [181]. Dietary Laminaria digitata (Phaeophyceae) and Gracilaria gracilis (Rhodophyta) significantly boosted the intestinal acid goblet cells of mullet (Liza ramada) [182] and European seabass (D. labrax) [183,184], which perform key roles in intestinal immune activity. Goblet cells act as a protector of intestinal barriers through the production and secretion of mucus and antimicrobial proteins (chemokines and cytokines), enhancing the local immune response of the intestine [185].…”