Microscopic Parasite ID Help

[bshonesy]

Can someone please help me ID the protist in these images. These were taken with a 10x objective and 25x eyepiece from a mucus scraping of a deceased clownfish that had no visible spots but had large mucus overproduction that resembled a brooklynella infection. However I have had an Angel, two tangs, a royal gramma and another clownfish die suddenly. The Angel had a huge amount of spots that appeared suddenly on the day he died, looking possibly like marine velvet but based on these images I’m wondering if this is actually ich. All of the sudden deaths and sometimes asymptomatic until death events have led me to believe this is velvet however. Any help would be appreciated.

 

[Jay Hemdal]

Looks like Cryptocaryon trophonts to me.

Jay

 

[bshonesy]

Looks like Cryptocaryon trophonts to me.

Jay

Thanks Jay, is it typical for fish die from infection without ever showing lesions from Cryptocaryon?

 

[Jay Hemdal]

Thanks Jay, is it typical for fish die from infection without ever showing lesions from Cryptocaryon?

No, it is not. However, it is possible for fish to died from some other issue while having a minor case of Cryptocaryon. How many protozoans did you see in each microscope field?

I've long suspected that there is another undifferentiated Ciliophoran that infects marine fish. I can't prove it and most people disagree with me. One issue is that it is VERY difficult to tell these apart with a light microscope, the variables such as age of the ciliate, back lighting and what it has been feeding on all work to give them different appearances.

Jay

 

[bshonesy]

No, it is not. However, it is possible for fish to died from some other issue while having a minor case of Cryptocaryon. How many protozoans did you see in each microscope field?

I've long suspected that there is another undifferentiated Ciliophoran that infects marine fish. I can't prove it and most people disagree with me. One issue is that it is VERY difficult to tell these apart with a light microscope, the variables such as age of the ciliate, back lighting and what it has been feeding on all work to give them different appearances.

Jay

Only one per field, and not very dense, I believe those were the only three I could find, but the clownfish had just been treated with a formalin bath and died in a QT tank with 1.5ppm Cu2+, so I'm not sure its a great indicator of density in the DT. I'm certainly just learning about all these parasites, but the rate at which I have lost fish would suggest something like Brooklynellosis or Amyloodinium ocellatum. All the symptoms are so confounding that I've been delaying treatment thinking I need to figure out what it is, but I think its time to just treat everyone with Cu2+ and hope for the best. Unless you have another suggestion. Thanks for your help.

 

[bshonesy]

I received an Aquabiomics eDNA report from a water sample that was taken a few days before I did these scrapings. It did confirm Cryptocaryon irritans was the only parasitic protozoan DNA detectable in the water column. Interestingly, it also detected that about 1-2% of the eDNA found matched with Microphallidae, an intestinal fluke. Can anyone recommend a treatment since I still have my fish in qt and is do these die off in the same fallow period as cryptocaryon?

 

[Jay Hemdal]

I received an Aquabiomics eDNA report from a water sample that was taken a few days before I did these scrapings. It did confirm Cryptocaryon irritans was the only parasitic protozoan DNA detectable in the water column. Interestingly, it also detected that about 1-2% of the eDNA found matched with Microphallidae, an intestinal fluke. Can anyone recommend a treatment since I still have my fish in qt and is do these die off in the same fallow period as cryptocaryon?

I'm not familiar with that group. they appear to be digeneans - which means they have multiple hosts to complete their life cycle (bird/fish/snail for example). Most digeneans are not fatal to aquarium fish because they cannot build up in sufficient numbers due to no secondary host. If you want to control them though, oral praziquantel is possible, but the dose is tricky. You could also try prazi in the tank itself since marine fish drink water from the tank.

If you want to go with oral meds, here is an article I wrote on that:

Proper Dosing of Medicated Foods

Proper Dosing of Medicated Foods Jay Hemdal c. 2020 Oral medications are an excellent way to target internal diseases of fishes. Marine fish absorb aquarium water, so in certain cases, they “drink” enough medication from the water to effect a cure. However, freshwater fish actively export...

www.reef2reef.com

Jay

 

[bshonesy]

I'm not familiar with that group. they appear to be digeneans - which means they have multiple hosts to complete their life cycle (bird/fish/snail for example). Most digeneans are not fatal to aquarium fish because they cannot build up in sufficient numbers due to no secondary host. If you want to control them though, oral praziquantel is possible, but the dose is tricky. You could also try prazi in the tank itself since marine fish drink water from the tank.

If you want to go with oral meds, here is an article I wrote on that:

Proper Dosing of Medicated Foods

Proper Dosing of Medicated Foods Jay Hemdal c. 2020 Oral medications are an excellent way to target internal diseases of fishes. Marine fish absorb aquarium water, so in certain cases, they “drink” enough medication from the water to effect a cure. However, freshwater fish actively export...

www.reef2reef.com

Jay

Thanks Jay, I will do the prazi in the water just in case, but if you're not alarmed by it then I'm not either.

 

[bshonesy]

just wanted to provide an update and post my Aquabiomics Pre and Post-fallow reports in case others come across this thread for sharing purposes. I’d also be curious for any advice folks have, and if Eli at @AquaBiomics (or anyone else) has any comment that might help me or others interpret these results better and make some decisions about how to proceed.

For one, I’d be curious to know whether this apparent reduction (quite dramatic from 84% of the total eDNA present in the sample to 0.03%) could be interpreted at erradication of live C. Irritans? Would you expect to get some DNA showing up from dead organisms that might account for this in the post-fallow sample?

I have put my fish back in and no sign of infection, but I have 3 fish at the end of their post-purchase qt that I am now scared to introduce. I really don’t want to go fallow again, and am considering getting a UV now since getting this report back, would that be an ok route?

 

[Jay Hemdal]

just wanted to provide an update and post my Aquabiomics Pre and Post-fallow reports in case others come across this thread for sharing purposes. I’d also be curious for any advice folks have, and if Eli at @AquaBiomics (or anyone else) has any comment that might help me or others interpret these results better and make some decisions about how to proceed.

For one, I’d be curious to know whether this apparent reduction (quite dramatic from 84% of the total eDNA present in the sample to 0.03%) could be interpreted at erradication of live C. Irritans? Would you expect to get some DNA showing up from dead organisms that might account for this in the post-fallow sample?

I have put my fish back in and no sign of infection, but I have 3 fish at the end of their post-purchase qt that I am now scared to introduce. I really don’t want to go fallow again, and am considering getting a UV now since getting this report back, would that be an ok route?

I think you would need to contact Aquabiomics for help interpreting these results - Eli has the experience comparing reports. Specifically - how often does he see < 0.05% Cryptocaryon in healthy tanks?

IMO - skip the UV for control of Cryptocaryon. It will, at most, just reduce the incidence of tomite/theronts, and the only true control that is seen is if water from one tank flows through a UV to a second tank, the second tank gains protection. In a side-stream situation, it just is not effective.

Jay