Effects of Nisin and lactoferrin immunostimulants on growth and resistance to pathogenic Vibrios in gnotobiotic Artemia test system (GART)

In this study, the effect of immunostimulants nisin and lactoferrin on the growth and survival of Artemia fransiscana in challenge with Vibrio campbellii and Vibrio proteolitycus under gnotobiotic conditions was investigated. Artemia was kept and cultured in gnotobiotic conditions for five days, and then Artemia nauplii were fed with killed LVS3 bacteria (a strain of Aeromonas hydrophyla) at the number of 10.5 x 109 cells per Falcon tube every day. Also, lactoferrin and nisin were added to the falcons in the required amount on a daily basis. On the third day, the pathogens V. campbellii and V. proteolyitus were added at a concentration of 5 x 106 cells/ml. This experiment included six treatments, the treatment in which Artemia was fed only with killed bacteria was considered as the control treatment. Each treatment consisted of four repetitions, and on the sixth day, the survival rate, longitudinal growth of nauplii and the total biomass (biomass) produced were checked. Lactoferrin increased daily survival percentage, relative survival percentage and total biomass produced against Vibrio campbellii and Vibrio proteolitycus, but a significant difference was obtained only in total biomass produced (p<0.05). Nisin increased the daily survival percentage, relative survival percentage and total biomass produced against Vibrio campbellii and Vibrio proteolitycus, but a significant difference was obtained only in the total biomass produced (p<0.05). Also, there was a significant increase in the individual length of Artemia in lactoferrin treatment against Vibrio proteolyticus. In general, the results showed that the use of lactoferrin and nisin as immune stimulants can increase the total amount of biomass and increase the resistance of Artemia to Vibrio infection in gnotobiotic environment.