PROBIOTIC P. acidilactici MA18/5M ENHANCES THE SHRIMP ANTIOXYDANT DEFENCES AND GROWTH: BENEFICIAL EFFECTS AND POSSIBLE PHYSIOLOGICAL MECHANISMS

High metabolic activity, increased environmental stress and infectious challenges are few conditions known to increase the intracellular production of reactive oxygen species (ROS) hence the need for higher antioxidant defense to protect cellular and animal integrity. Accordingly, the beneficial effects of in-feed antioxidants to sustain animal health and performance start to be recognized across the livestock industry. There is less notoriety about the potential link between (dietary) carbohydrates metabolism and the antioxidant system, particularly as a mechanism by which probiotics can positively influence the animal's oxidative status.

A controlled feed-intake trial documented the positive influence of the well know probiotic P. acidilactici MA18/5M on the growth, carbohydrate digestibility, glycemia and antioxidant status of peneid shrimp (Fig). The positive effect of probiotic on the shrimp antioxidant status was further confirmed under semi-commercial conditions as well as when exposed to a controlled vibriosis challenge where enhanced survival was also documented. As supported by knowledge in other species, it is hypothesized that enhanced carbohydrate utilization as a result of P. acidilactici would decrease cellular oxidative stress level via the direct ability of glucose to scavenge OH-radicals or by fueling the pentose-phosphate pathway generating NADPH. NADPH is indeed key player against oxidative stress and free radicals propagation in particular.

Together, this shades light on a scarcely explored mechanisms by which the probiotic P. acidilactici MA18/5M can enhance shrimp health status and growth via its nutritional benefits.