Supplementing the diet of Nile tilapia (Oreochromis niloticus) with Amphora coffeaeformis nanoparticles (Am NPs) enhances the growth performance, redox status, digestion, immune responses, and defense against Aeromonas veronii

Abstract

A frequent species of microalgae in alkaline brackish, marine, and freshwater is Amphora coffeaeformis. It has a high concentration of physiologically active chemicals with antibacterial, anti-obesity, and antioxidant properties, as well as pigments involved in photosynthetic respiration, including as carotenoids and chlorophyll, that are effective in a range of medical applications. The current study sought to determine the effects of varying dosages of Amphora coffeaeformis nanoparticles (Am-NPs) incorporated diet on Nile tilapia (Oreochromis niloticus), which were weighted at 15±0.5 g and 9±0.5 cm in length, on growth performance, immunological, digestive enzymes, lipid peroxidation, and antioxidant activities, as well as histological examination of the intestinal villi and resistance to Aeromonas veronii (A. veronii). Four experimental groups (each with 80 fish) were run in duplicate. For four weeks, Amphora nanoparticles (Am NPs) at 2.5, 5 and 7.5 g/kg diet were added to the following three groups, while the first additive-free basal diet functioned as the control group. After the feeding trial, fish were exposed to an infection of pathogenic bacteria (A. veronii) with 9×108 CFU/ml. Supplementing with (Am-NPs) during the experiment period, specifically 7.5 g/kg diet (P˂0.05), significantly improved the following: immunological parameters such as liver Nitric oxide (NO) and plasma IgM and IgG; biochemical parameters such as liver tissue alanine aminotransaminase, aspartate aminotransaminase, plasma lipase, and amylase; and growth performance (weight gain, specific growth rate, feed conversion rate, and length gain rate). The villus height, the villus height to crypt depth ratio and and the number of goblet cells were significantly (P<0.05) increase in the fish fed Am Nps especially at 7.5 g/ kg diet when compared with control group which had the lowest values. Additionally the supplemented groups showed a substantial (P<0.05) decrease in the crypt depth of the villus when compared to control group. Our results showed that the groups treated with Am-NPs had a relative percent survival (RPS) of 65-85% against the infection of pathogenic Aeromonas veronii bacteria, compared to a control group that had an RPS of 0%. In conclusion, Amphora coffeaeformis offers several advantages, the chief among them being that it is a significant food source. Additionally, it has a range of physiologically active substances with antibacterial, immunological, antioxidant, and biochemical properties that are used in numerous medicinal applications.