Microbial Communities Associated With Stunted Growth Syndrome In Penaeus Vannamei Farming

Abstract

Purpose: Stunted/slow growth syndrome is one of the yield-limiting diseases in Penaeus vannamei farming. Limited information is available on the aetiology of this condition, which needs to be studied to devise prophylactic measures to minimise the production losses. Amongst the factors that influence this condition, microbial communities in the growing environment play an important role. This study aimed at understanding major microbial associations of affected and healthy pond waters through shotgun metagenomics.Method: The water samples were filtered through vacuum filtration to extract suspended microbes. Subsequently, DNA was isolated from the filtrate using PowerSoil® DNA Isolation Kit. Libraries prepared from isolated DNA were sequenced using the shotgun metagenomic method on the Illumina HiSeq platform. The microbial profiling and their functional prediction of the shotgun metagenome sequences were carried out using stand-alone versions of Kaiju, OmicsBox respectively. Results: The taxonomic classification results revealed that species of Oceanospirillum, and vibrio were high in the disease sample, while Rhodobacteraceae bacterium and Neptunomonas were high in the healthy sample. The alpha diversity analysis showed slightly higher diversity in the healthy sample compared to the disease infected. The taxonomic biomarkers for healthy and infected states reported in previous studies were also observed in this study. The major functional associations of both the healthy and infected groups include amino acid transport and metabolism, cell wall/membrane/envelope biogenesis, and energy production and conversion. Conclusion: The study identified major taxonomical and functional associations of ponds affected and unaffected with stunted growth syndrome. These associations significantly varied between the samples, indicating dysbiosis of the microbial profiles in the pond waters. This dysbiosis could be a potential cause for the manifestation of stunted growth syndrome. Microbial associations along with other pond environmental factors need to be further explored for an in-depth understanding of stunted growth syndrome.

Oyster Reefs Are Reservoirs for Potential Pathogens in a Highly Disturbed Subtropical Estuary

“…The orders that dominated biodeposit samples also varied in their potential to contain pathogens. For example, Vibrionales and Campylobacterales, which were abundant in January, have been frequently associated with human and animal diseases [69,144,[160][161][162]. Conversely, Geobacterales, which was abundant in the July biodeposit samples, is potentially quite beneficial.…”