The effect of zymosan immunostimulant on artemia growth and resistance to vibrio infection in a gnotobiotic artemia test system

One of the most useful methods of increasing resistance through impact on the aquatic immune system is trying  to boost the immune system through various ways such as vaccination and the use of immune enhancers such as immune stimulants, probiotics and glucan compounds etc. Modern fish farming systems are common. The use of immunostimulants in gnotobiotic system is one of the new methods to prevent and control the aquatic diseases by realizing the mechanisms involved in host-microbe interactions. This study was designed to investigate the effect of zymosan immunostimulant on Artemia fransiscana growth and resistance to Vibrio campbelliiand Vibrio proteolyticus infections in a gnotobiotic system. Artemia nauplii were fed with killed LVS3, about 10.5×109 cells per falcon tube per day (control). Zymosan was added in an amount of 30.6 mcg per falcon tube daily in experimental treatments. On the third day, V. campbellii and V. proteolyitus pathogens were added at 5 ×10 ⁶ cell /ml. On the sixth day of the experiment, zymosan increased the percentage of daily survival against V. campbellii (54.49±1.53) compared with control (31.72±9.87), relative percentage of survival (80±0.08) compared with control (47±0.17) and total biomass production (21.17±0.18) compared with control (9.04±4.46) (p<0.05). Although zymosan increased the percentage of daily survival, the relative percentage of survival and total biomass production against V. proteolyticus compared with the control, but the differences were not significant (p>0.05). Zymosan also had positive impact on the individual length of challenged artemiawithV. campbellii and V. proteolyticus, however that was not significant compared with the control (p>0.05). In conclusion, the results revealed that the zymosan as an immunostimulant could increase the artemia resistance against vibrio infections in gnotobiotic environment.