White feces syndrome (WFS) remains a widespread concern for the shrimp farming sector and has caused severe economic losses across Asia. A trial conducted by Lallemand Animal Nutrition and Loc Tran from ShrimpVet Laboratory in Ho Chi Minh City, Vietnam tested yeast derivatives on juvenile shrimp that were challenged with WFS.

Despite the challenging conditions, the yeast derivatives improved shrimp performance lowering the severity of the WFS outbreak with less tissue damage in the gastrointestinal tract. The reshaping of the gut microbiota by WFS was mitigated by the yeast product. In particular, the relative abundance of Vibrio sp. was decreased, which seems to have reduced the severity and impact of the disease.

Eric Leclercq, Aquaculture Technical Support and R&D Manager for Lallemand Animal Nutrition said that “we have already shown very interesting benefits to shrimp defenses when using our innovative multi-strain yeast fraction solution. With Dr. Tran, we wanted to explore the mode of action of this natural solution in the context of WFS. We looked at the yeast derivative’s effects on shrimp performance and gut histopathological damages, and also on gut microbiota thanks to the latest techniques in metagenomics studies.”

Researchers say that this shift in intestinal microbiota suggests a role of the commensal microbiota in the pathogenesis of the WFS. The study hints towards the potential of reinforcing the intestinal microbiota equilibrium against Vibrio sp.-induced disruption that could mediate WFS.

These results were presented at the Asian-Pacific Aquaculture 2019 Conference in Chennai, India.

Source: Leclercq E., Achard C., Ralite S., Tran L., and Castex M. Gut microbiata and histopathological changes associated with WFD in juveniles Litopenaeus vannamei and the modulating effect of a multi-strains yeast fraction product. Asian-Pacific Aquaculture 2019, June 19 - 21, 2019, Chennai (India).