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