Effect of Padina astraulis Hauck algae feeding on the mucus resistance indeces of Cyprinus carpio in exposure to silver nanoparticles

The present study was carried out to investigate the effect of Padina astraulis hauck on common carp (Cyprinus carpio) mucus resistance indeces. According to this, a total of 250 fry with an average weight of 20±4 g in were introduced into four treatments each with three replications, including diet without algae (control), diet with 0.5% algae (Treatment 1), diet with 1% algae (Treatment 2) and diet with 2% algae (Treatment 3) and fed for 42 days. At the end of the feeding period, treatments wer exposured to silver nanoparticles at concentrations of 0.5%. At the end of experiment, sampling of fish mucus was performed. The results showed that the highest protein content of mucus was observed in 1 and 2% treatments and the lowest one in 0.5% treatment and control and there was no significant difference between treatments. The highest increase in lysozyme and ALP of the mucus were observed in 1 and 2% treatments and the lowest one in 0.5% and control group (P