Related Experiment Videos
Bacteria in bivalve shellfish with special reference to the oyster.
The Journal of Applied Bacteriology
|July 1, 1985
Summary
Bivalve shellfish like oysters and mussels harbor distinct bacterial communities, primarily Pseudomonas species, differing significantly from seawater. Their digestive tracts show a higher density and unique composition of bacteria compared to surrounding waters.
Area of Science:
- Marine microbiology
- Bivalve aquaculture
- Gastrointestinal microbiology
Background:
- The bacterial flora of marine bivalves is crucial for their health and the aquatic ecosystem.
- Understanding the composition and dynamics of bacterial communities in shellfish is essential for aquaculture and environmental monitoring.
Purpose of the Study:
- To characterize and compare the bacterial flora of Pacific oysters (Crassostrea gigas), sea mussels (Perna viridis), and arkshell clams (Scapharca cornea) with that of the surrounding seawater.
- To investigate the distribution and density of bacteria within the digestive tracts of these bivalves.
Main Methods:
- Isolation and characterization of bacterial strains from bivalve tissues and seawater samples.
- Quantitative analysis of heterotrophic bacteria, anaerobes, and spore-forming bacteria.
- Identification of dominant bacterial genera using microbiological techniques.
Main Results:
- Bacterial numbers and generic composition in bivalves significantly differed from seawater.
- Pseudomonas spp. were dominant in bivalves, comprising over one-third of isolated strains.
- Deposit-feeding clams exhibited higher bacterial density and distinct flora compared to suspension-feeding oysters and mussels.
- Over 90% of bacteria in oysters were concentrated in digestive organs, with coliforms in the stomach and heterotrophs in the stomach and lower intestine.
Conclusions:
- Bivalve shellfish harbor distinct bacterial communities, with Pseudomonas species being predominant.
- Bacterial flora in bivalves is significantly influenced by their feeding strategies (deposit vs. suspension feeding).
- Oyster digestive tracts, particularly the stomach, serve as a primary site for environmental bacteria, with potential for indigenous flora development in the lower intestine.