Publication Date:
2022-07-10
Description:
Bacterial diseases cause production failures in shrimp aquacultures.to understand environmental
conditions and bacterial community dynamics contributing to white faeces disease (WFD) events,
we analysed water quality and compared bacterial communities in water as well as in intestines and
faeces of healthy and diseased shrimps, respectively, via 16S rRNA gene sequencing and qPCR of
transmembrane regulatory protein (toxR), thermolabile haemolysin (tlh), and thermostable direct
haemolysin genes of pathogenic Vibrio parahaemolyticus as a proxy for virulence. WfD occurred
when pH decreased to 7.71–7.84, and Alteromonas, Pseudoalteromonas and Vibrio dominated the
aquatic bacterial communities. the disease severity further correlated with increased proportions of
Alteromonas, Photobacterium, Pseudoalteromonas and Vibrio in shrimp faeces. these opportunistic
pathogenic bacteria constituted up to 60% and 80% of the sequences in samples from the early and
advances stages of the disease outbreak, respectively, and exhibited a high degree of co-occurrence.
Furthermore, toxR and tlh were detected in water at the disease event only. Notably, bacterial
community resilience in water occurred when pH was adjusted to 8. Then WFD ceased without a
mortality event. In conclusion, pH was a reliable indicator of the WFD outbreak risk. Dissolved oxygen
and compositions of water and intestinal bacteria may also serve as indicators for better prevention of WFD events
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
NonPeerReviewed
Format:
application/pdf
Permalink
