Impact of MY-1 and Enterotrophotic as probiotics on growth and survival of Macrobrachium rosenbergii post-larvae during pre- and post-challenge with Vibrio alginolyticus

The study examined the effects of different probiotics on growth, survival, and immune gene expression in Macrobrachium rosenbergii post-larvae (PL). The PL were fed with MY-1, Enterotrophotic (ENT), and MY-1 + Enterotrophotic (MY-1 + ENT) enriched artemia for a duration of 20 days, with three feedings per day. Throughout the experiment, water quality parameters were closely monitored. Results showed that the postlarvae fed with MY-1 + ENT exhibited better growth in terms of size and weight compared to the other groups. On the 21st day, both the control and treated PL were exposed to pathogenic Vibrio alginolyticus. The groups administered with MY-1 + ENT had higher survival rates compared to the other treatment and control groups. Moreover, the expression levels of immune-related genes such as cytochrome oxidase (COX), prophenoloxidase (proPO), peroxinectin (PE), antilipopolysaccharide (ALF), and lipopolysaccharide glucan binding protein (LGBP) were examined through qPCR. The results indicated a variable expression pattern suggesting that the application of probiotics enhances the expression and regulation of immune genes in the event of infection by V. alginolyticus. The differences in gene expression highlight the opportunity to develop Immune Gene Expression Finger Printing, which may act as an effective tool for evaluating probiotics and immunostimulants by assessing their ability to modulate immune responses in M. rosenbergii. The study warrants field-level validation of the findings to facilitate the adoption in the hatchery technology for scampi seed production too.