White Feces Syndrome (WFS) refers to the floating white fecal strings in ponds where shrimp are reared. WFS is associated with shrimp growth retardation, size disparities and reduced feeding and chronic mortalities and has become a serious issue in P. vannamei and P. monodon farms in Southeast Asia.
Recently WFS has been associated with the presence of Enterocytozoon hepatopenaei (EHP) and a V. parahaemolyticus ToxR+ PirAB- isolate and a controlled co-infection in shrimp in a laboratory setting with the isolates resulted in WFS.
The goal of this study is to acquire information about the microbial populations in ponds exhibiting WFS and how best to use probiotics to mitigate the syndrome. In this preliminary study we captured microbes from water samples on filters for analysis in the laboratory. Also, water samples from a WFS+ and - pond were plated on TCBS and TSB plates, the CFUs were determined and isolates were identified and characterized (Table 1). Noteworthy was that the WSF- ponds contained more vibrio and more microbes on TSB plates (3.2 X 104 CFU/ml vs 5.3 X 102 CFU/ml data not shown).
Inhibition studies between vibrio’s from WFS+ and – ponds and inhibition between vibrio’s from WFS+ ponds and potential probiotics will be presented. The implications to pond management from these results will be discussed and future studies will be addressed.