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Published on: December 8, 2017
Pseudomonas sp. M174 inhibits the fish pathogen Flavobacterium psychrophilum
T L Korkea-aho1, J Heikkinen, K D Thompson
1Institute of Aquaculture, University of Stirling, Stirling, UK. tk8@stir.ac.uk
Aims:
To study the antagonic affect of probiotic Pseudomonas M174 on the fish pathogen Flavobacterium psychrophilum.
Methods And Results:
The ability of Pseudomonas M174 to inhibit the growth of Fl. psychrophilum was examined in iron-sufficient and -deficient media. Possible siderophore production was also investigated. Antagonistic activity was confirmed in disease challenge experiments using a rainbow trout (Oncorhynchus mykiss) model. Adhesion of Pseudomonas M174 to fish surfaces and its ability to stimulate innate immunity was also investigated in vivo. Pseudomonas M174 antagonized Fl. psychrophilum and produced siderophores in vitro. In challenge experiments with Fl. psychrophilum, fish fed with Pseudomonas M174 had lower levels of mortalities than the controls. It was possible to find Pseudomonas M174 in the intestinal content of these fish after feeding and bathing with the probiotic, but probiotic was obtained from the gills only after feeding. Respiratory burst activity was also found to be enhanced in the M174 fed fish.
Conclusions:
These results suggest that M174 is a potential probiotic against Fl. psychrophilum and has several modes of action.
Significance And Impact Of The Study:
Probiotics are a promising alternative to the use of antibiotics in aquaculture and could be a more sustainable disease control method.
Insights
The probiotic Pseudomonas M174 effectively inhibited the fish pathogen Flavobacterium psychrophilum. This study shows M174 is a potential sustainable alternative to antibiotics in aquaculture.
Area of Science:
- Aquatic microbiology
- Fish immunology
- Probiotic research
Background:
- Aquaculture faces challenges from fish pathogens like Flavobacterium psychrophilum.
- Antibiotic use in aquaculture raises sustainability and resistance concerns.
- Probiotics offer a promising alternative for disease control in fish.
Purpose of the Study:
- To evaluate the antagonistic effect of the probiotic Pseudomonas M174 against Flavobacterium psychrophilum.
- To investigate the mechanisms of action of Pseudomonas M174 in controlling fish diseases.
Main Methods:
- In vitro growth inhibition assays of Fl. psychrophilum by Pseudomonas M174.
- Siderophore production analysis by Pseudomonas M174.
- Disease challenge experiments in rainbow trout (Oncorhynchus mykiss) models.
- In vivo analysis of probiotic adhesion and immune stimulation.
Main Results:
- Pseudomonas M174 demonstrated in vitro inhibition of Fl. psychrophilum growth and produced siderophores.
- Fish challenged with Fl. psychrophilum showed reduced mortality when fed Pseudomonas M174.
- Pseudomonas M174 was detected in fish gut content, and respiratory burst activity was enhanced.
Conclusions:
- Pseudomonas M174 exhibits antagonistic activity against Fl. psychrophilum through multiple modes of action.
- The probiotic Pseudomonas M174 is a viable candidate for sustainable disease management in aquaculture.
- Probiotics represent a more sustainable approach to disease control compared to traditional antibiotics.
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