Probable new approach in STN syndrome?

[Jose Mayo]

I have been reading, here and there, that the relationship of the white band disease with the effect of a combination of infectious factors, acting in a moment of fragility of the coral, is practically defined. On the other hand, there seems to be pathophysiological similarity between WBD and STN, being the same mechanism perhaps involved in the two conditions.

A recent study, in Caribbean corals, suggest a combined antibiotic approach in aquarium "hospital", successful in treating the syndrome and guides the treatment protocol.

I leave the link, for your appreciation and discussion:

Experimental antibiotic treatment identifies potential pathogens of white band disease in the endangered Caribbean coral Acropora cervicornis

Highlights:
"Although antibiotic treatments could be used as a potential cure for WBD in the field, extreme care would need to be taken as many microbes are known to develop resistance to antibiotics [34,35]. Furthermore, such treatments might have unwarranted effects on other host–microbe interactions in the natural environment. It would be unfeasible and unethical to apply antibiotic treatment at the regional and global scale of coral disease zoonoses, but it would probably be effective to use ampicillin or paromomycin sulfate treatment in specific circumstances where collateral effects could be minimized, for example in aquarium treatments."
[...]
"Four types of antibiotics were used in treatments to determine their effects on the diseased corals; ampicillin, gentamicin, metronidazole and paromomycin sulfate. 100 µg ml−1 was used for all four antibiotics after preliminary laboratory trials on both bacteria and healthy corals. The antibiotics were added directly into tanks filled with 3 l of seawater collected from the original location of the corals. Repeat dosage was dissolved in 1.5 l of seawater every 12 h, and half the water in the experimental tanks was replaced with the new water. n = 6 corals were used per treatment (n = 2 per tank, three tanks). One set with WBD were left untreated in the tanks and sampled before all the tissue had been lost. Healthy corals were also collected and held in the aquaria for the duration of the experiment to address any tank effects on the health of the corals. Prior to the onset of the main experiment, healthy corals were also treated with the antibiotics at the same dose rates used within the experiment to ensure that the antibiotics were having no adverse effect on the corals. All these treatments survived to the end of the experiment with no visual appearance of tissue deterioration or discoloration."

Best regards

 

[Tahoe61]

Thanks for sharing.

I know there is WBD to LPS that was either bacterial or viral. I always assumed STN in Acropora is a symptom of a multitude of pathogens or chemistry issues.

 

[Hedgedrew66]

Are people reacting to this study ? Are people dosing tanks or moving fragged specimens to antibiotic tanks ??? Article doesn’t talk much about the time to react to save coral.

 

[Jose Mayo]

As far as I know, there is still no experience in aquarism with this treatment, but some things I know, I can say:

- The best ampicillin for aquaristic purpose is the injectable, for human intravenous use. It comes in bottles of 500 or 1000 mg in the form of powder for diluition in distilled water for injections or RO / DI.

- It is diluted with 2 to 3 ml of water in the vial itself, and then this first dilution and re-diluted in 98 or 97 ml of water, giving a concentration of 5 or 10 mg / ml at this dilution.

- At this dilution, at room temperature, it is stable for up to 12 hours, after which time autocatalysis begins. For this reason, it should be administered to the aquarium every 12 hours, with partial changes of water, to avoid accumulation.

- The dosage used in the experiment under controlled conditions and with pharmaceutical grade drugs of known origin was 1.0 mg / liter every 12 hours with 50% water exchange.

- Ampicillin alone was able to halt the WBD process in the tested acropores, being considered cured with six days of treatment without progression of the lesions.

- Ampicillin did not act on the protozoan Philaster lucinda, who is able to eat live coral tissue on the banks of the lesion, but Metronidazole did the job of eliminating it, at the same dosage of 1 mg / liter 12/12 hours.

- The combined use of the two drugs, at the dose described, appears to have potential to control coral disease under aquarium-hospital conditions within six days, according to the study presented above.

Although this study seems promising, there is so far no use protocol that contemplates this approach in aquarism. In an approximate drawing, and in my opinion, the sick coral should be transferred as soon as possible to a treatment environment with the minimum support conditions, such as water oxygenation (air injection by porous stone), blue spectrum light, good circulation and stable temperature, according to the requirements of the species. Because of frequent water changes, I believe that levels of ammonia and nutrients are not a concern.

Best regards

 

[Hedgedrew66]

Yes

As far as I know, there is still no experience in aquarism with this treatment, but some things I know, I can say:

- The best ampicillin for aquaristic purpose is the injectable, for human intravenous use. It comes in bottles of 500 or 1000 mg in the form of powder for diluition in distilled water for injections or RO / DI.

- It is diluted with 2 to 3 ml of water in the vial itself, and then this first dilution and re-diluted in 98 or 97 ml of water, giving a concentration of 5 or 10 mg / ml at this dilution.

- At this dilution, at room temperature, it is stable for up to 12 hours, after which time autocatalysis begins. For this reason, it should be administered to the aquarium every 12 hours, with partial changes of water, to avoid accumulation.

- The dosage used in the experiment under controlled conditions and with pharmaceutical grade drugs of known origin was 1.0 mg / liter every 12 hours with 50% water exchange.

- Ampicillin alone was able to halt the WBD process in the tested acropores, being considered cured with six days of treatment without progression of the lesions.

- Ampicillin did not act on the protozoan Philaster lucinda, who is able to eat live coral tissue on the banks of the lesion, but Metronidazole did the job of eliminating it, at the same dosage of 1 mg / liter 12/12 hours.

- The combined use of the two drugs, at the dose described, appears to have potential to control coral disease under aquarium-hospital conditions within six days, according to the study presented above.

Although this study seems promising, there is so far no use protocol that contemplates this approach in aquarism. In an approximate drawing, and in my opinion, the sick coral should be transferred as soon as possible to a treatment environment with the minimum support conditions, such as water oxygenation (air injection by porous stone), blue spectrum light, good circulation and stable temperature, according to the requirements of the species. Because of frequent water changes, I believe that levels of ammonia and nutrients are not a concern.

Best regards

I agree. And I will be in a position to experiment with that combined protocol.

 

[JaimeAdams]

I have read that study and have seen it posted multiple times to the forum. It's a very interesting read.

 

[McMullen]

Good stuff
Potential to advance the hobby here.

 

[Flippers4pups]

http://www.artificialreefs.org/Corals/diseasesfiles/Common Identified Coral Diseases.htm

Coral gets weakened by environmental stress and bad bacteria that exist around the the tissue naturally, then attacks. Interesting reading. Sorry hijacking.

 

[Flippers4pups]

Here's a video presentation on bacteria and coral reefs explaining the bacterial relationship with coral and environmental stressors.

 

[Hedgedrew66]

This Stn rtn can spreads like wild fire in a dense reef tank. So even though we might be able to save a few prize specimens seems like we need an in tank treatment or a way to prevent bacteria to multiply to begin with. I think this was behind bob starks bleach thesis. Huge uv ? I’m not sure the answer but taking out corals one by one and treating is only a partial answer

 

[Flippers4pups]

This Stn rtn can spreads like wild fire in a dense reef tank. So even though we might be able to save a few prize specimens seems like we need an in tank treatment or a way to prevent bacteria to multiply to begin with. I think this was behind bob starks bleach thesis. Huge uv ? I’m not sure the answer but taking out corals one by one and treating is only a partial answer

It seems that thin tissue locations on a stressed coral is where the event starts. Its unclear if the bacteria are the ones that start the tissue damage, or are just taking advantage of "something" else causing the tissue death.

The use of antibiotics to combat this sounds promising, but there's issues with that:

1). Gram negative bacteria don't always respond to antibiotics. More often not.
2). Prophylactic application of antibiotics can lead to resistant strains of bacteria. We hear this all the time even in our use of antibacterial soaps and cleaners.
3). Since we can't culture all the different strains of bacteria on the reef, nearly impossible, we can't engineer antibiotics to combat the bad bacteria. Bacteria that resides on one coral maybe totally different on a neighboring coral.....and so on and so on.....

The only course that makes sense in the here and now is what reefers have been doing for decades, frag above the damage and discard the damaged tissue without broadcasting it throughout the tank.

 

[Jose Mayo]

This Stn rtn can spreads like wild fire in a dense reef tank. So even though we might be able to save a few prize specimens seems like we need an in tank treatment or a way to prevent bacteria to multiply to begin with. I think this was behind bob starks bleach thesis. Huge uv ? I’m not sure the answer but taking out corals one by one and treating is only a partial answer

The biggest obstacle to antibiotic treatment directly in the tank is the biological filter; broad-spectrum antibiotics such as ampicillin and others are able to target and decimate both harmful and useful bacteria, which would practically involve restarting the tank, which is not desirable.

In bare bottom systems with artificial rocks and mature RSDB or a good set of sintered glass media, it could be tempting to isolate the sump to preserve it while performing DT treatment, but in a traditional montage it is very risky. In these cases, the best solution is to remove the animal to be treated and return it to the DT after treatment.

In this study, although many bacteria related to the lesion were identified, due to differences in response, especially in relation to the stopping or progression of the disease, the bacteria of the genus Vibrio sp and Roseobacter sp were found to be the most probable cause and maintainers of the disease. There is also a ciliated protozoan, Philaster lucinda, also present and active in the lesions, which is able to ingest live tissue from the sick coral, but does not appear to be responsible for initiating or maintaining the disease in healthy corals.

From what has been seen so far, it seems that this disease is actually promoted by an adverse conjugation of infectious factors, composed primarily of bacteria and protozoa and, secondarily, of some microalgae and fungi that associate to participate in the feast.

The triggering factor can be any more stress that the coral receives, and thereby diminishes its defenses; a highly eutrophic environment (very rich in nutrients) may be one, abrupt variations in temperature may be other, aggressions by other predators, imbalance in the microbiota associated with its surface (either by sugars excreted by algae or sponges, or allelochemicals from these same sources or of other corals), other.

The presence of heavy metals (copper, silver, nickel, cadmium, boron, neodymium), cyanotoxins, dinotoxins, leakage of electric current in the aquarium, been absent or excess of trace elements (read lack of WC, or dosage without criterion), have also reported as probable triggering causes and so on.

For these reasons, and even if antibiotic treatment is effective in controlling the disease, the permanence of triggering factors without investigation and correction in the aquarium environment can cause the final result to be the failure.

Best Regards

 

[Hedgedrew66]

I agree with this. Although from the article I interpreted the bacteria to maybe gram positive which is interesting in itself. Frankly I would have chosen different antibiotics to use in the experiment I’m not sure why ampicillin was chosen unless gram positive was suspected. And I would have used more widely accessible broad spectrum choices.

 

[Jose Mayo]

I agree with this. Although from the article I interpreted the bacteria to maybe gram positive which is interesting in itself. Frankly I would have chosen different antibiotics to use in the experiment I’m not sure why ampicillin was chosen unless gram positive was suspected. And I would have used more widely accessible broad spectrum choices.

Often, the "salt water" context substantially alters the expected response to antimicrobial agents. The efficacy of tetracyclines in bacteria of the genus Vibrio sp. is known, but in marine environments the high concentration of calcium ions, for which tetracyclines have high affinity, almost invalidate their usefulness for treatment.

Note that, in this experiment, gentamicin, known to be highly effective in Gram-negative bacteria, was also used, but failed completely in the control of WBD. Ampicillin, in turn, acts well on Gram-positive and not-so-well on Gram-negative bacteria, but, in the context of the marine water experiment, was able, alone, to halt the progression of the disease.

Best regards

 

[Hedgedrew66]

Correct. I suspect they should have tried cipro or kanamycin or even erythromycin if gram positive suspected.

 

[revhtree]

Very interesting!

 

[rosshamsandwich]

Why not iodine dip them then?

 

[Cnidoblast]

I would like to see research done into clindamycin treatment - but it would destroy all your nitrifying bacteria

 

[salty joe]

Why not iodine dip them then?

Yeah, gram positive/negative, interference from ions becomes irrelevant.

 

[Velcro]

- The dosage used in the experiment under controlled conditions and with pharmaceutical grade drugs of known origin was 1.0 mg / liter every 12 hours with 50% water exchange.

Are you sure about that dosage? I'm seeing 100 microgram/mL which would be 100 mg/L

Also, I'm not seeing a duration of the bath that they did. I see they studied the corals for 6 days but are we to assume that they were doing the redosing and water change every 12 hours for 6 days?

I'm looking at doing this treatment and was really hoping to get away with 24 hours