AUTHOR=Ashour Mohamed , Ali Fawzia S. , Mamoon Ahmed , Mansour Ahmed I. A. , Mabrouk Mohamed M. , Mansour Abdallah Tageldein , Mohamed Ehab , Abdelhamid Ahmed F. 

TITLE=Pterocladia capillacea polysaccharide enhances growth, immunity, digestive enzyme, antioxidant activities, and gene expressions of Litopenaeus vannamei

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 12 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2025.1594751

DOI=10.3389/fmars.2025.1594751

ISSN=2296-7745

ABSTRACT=This work evaluated the effects of dietary supplementation with the seaweed polysaccharide (PS) extracted from red seaweed, Pterocladia capillacea, on the growth, feed efficiency, whole-body composition, immunological response, antioxidant activity, digestive enzyme activities, and gene expression of the whiteleg shrimp, Litopenaeus vannamei. Four isonitrogenous and isoenergetic diets with different SP levels were formulated. The basal experimental diet (control diet) had no seaweed polysaccharide added (PS0). Diets 2–4 (PS1, PS2, and PS3) were formulated to contain PS at levels of 1, 2, and 3 g/kg diet, respectively. Six hundred postlarvae (PLs15; with an initial body weight of 1.62 ± 0.12 g/PL) of the whiteleg shrimp L. vannamei were randomly selected and distributed into triplicate hapas per treatment. For the duration of the 60-day trial, the PLs were fed their corresponding diets three times a day at 10% of their body weight. Compared with those in the control diet and PS3, the shrimp reared in groups PS1 or PS2 showed significant (p< 0.05) improvements in the specific growth rate, survival rate, length gain rate, and weight gain rate. The individuals in the PS2 group showed the greatest significant (p< 0.05) values of the feed conversion ratio, feed efficiency ratio, and protein efficiency ratio. In addition, the shrimps in the PS2 group showed the highest significant values (p< 0.05) of lysozyme, amylase, lipase, and SOD, and the highest significant value of MDA, whereas the shrimp in the PS3 group showed the highest significant values (p< 0.05) of catalase. The expression levels of investigated growth-related genes (GH, IGF-1, and IGF-II) and immunity-related genes (Proph, SOD, and Lys) in the PS2 group were significantly (p< 0.05) increased. In conclusion, the supplementation rate of 2 g/kg PS significantly improved the growth, nutrient utilization efficiency, nonspecific immunity, antioxidant and digestive enzyme activities, and improved the immunity- and growth-related gene expression of L. vannamei shrimp. However, future works are recommended to understand the mechanism by which PS enhances physiological status and modulate genes expression in whiteleg shrimp.