Pathogens, environmental stressors and opportunistic diseases are ubiquitous in aquaculture. Achieving efficient and profitable production, especially with the increasing global threat of antimicrobial resistance, is critical for producers. Helping aquaculture species to better perform with infectious and physiological pressures is therefore of high interest and a focus of research.
To assess the bacterial aggregation capacity of Pg in vivo, a bacterial clearance study was performed: Litopenaeus vannamei shrimp were injected with Vibrio harveyi. Three hours post-injection, V. harveyi concentration in hemolymph in the Pg fed shrimp was more than 3 times lower compared to control-fed shrimp (Fig 2). It was also shown that the granular hemocyte concentration in hemolymph was 56% higher after 4 weeks in Pg fed shrimp compared to that in control shrimp. (Fig 3) . Granular hemocytes are key for an effective and rapid immune response in shrimp, and represent an ideal parameter in monitoring shrimp immune potency.
In order to confirm the potential benefit of Pg in shrimp culture conditions, 2 challenge studies were performed in L. vannamei shrimp supplemented with 0.1% Pg4: Survival of shrimp 5 weeks after White Spot Syndrome Virus challenge increased by 84% compared to unsupplemented control shrimp, whereas it was 76% higher 5 weeks after V. parahaemolyticus challenge. In field conditions without specific pathogenic challenge,