Medications and Lowered Salinity

dive girl

dive girl

Member
I didn't want to hijack any thread, so I thought I'd start a new one. I'm a 'why' asker. I like to know the ins and outs and the whys and why-nots. I ask questions and tend to wonder things over.
So I was wondering about salinity and medications....
Neomycin is a medication that is tough on the kidneys, this is a fact not my opinion.
In a different thread I had posted that maybe the salinity should be lowered when treating a seahorse with antibiotics and was told that it should not be. I'm sure there has got to be a reason, but I just don't know why. I had a seahorse that contracted tailrot after a surface abrasion. I finally found a vet that was willing to see him (though it turned out to be too late). She admitted that she had not treated fish before and was going on some recommendations that I had been given and shared with her. She called one of her prior classmates that does treat fish and one of the recommendations he made was to lower the salinity which I had done previously based on another's recommendations.
Lowered salinity keeps more oxygen in the water and can help reduce the metabolic work-loads of our fish (I'm not including inverts or corals in this statement). When we lower the salinity slightly we are lowering the osmotic pressure in the water. (All fact, not my opinion)
Here's my thoughts on this as related to my nursing background:
If we are lowering the osmotic pressure of the water, it takes less effort for our seahorses to retain freshwater (metabolic work-load) which they require to survive. So basically, if we are treating with an antibiotic that is known to cause kidney damage wouldn't we want to lower salinity to increase hydration in our fish to help keep the kidneys flushed?
We know that a lower salinity can cause certain organisms to die, ich and parasites. I did a fresh water dip on a new seahorse of mine that I have in QT. Speaking of QTs, I keep my QTs at a lower salinity as well. So, when we use lowered salinity as a routine treatment, why don't we use it with a fish that we are treating with antibiotics?
I'm talking about a specific gravity of somewhere around 1.016-1.020 (based on the recommendations from the vet).
I'm not pretending to know anything about the treatment of disease in seahorses other than what I've learned first hand (and my boy didn't survive). This vet could have been incorrect but I also checked with others that have had success in raising and treating seahorses and they didn't feel that it would be harmful to lower my salinity slightly.
There is probably a reason as to why we wouldn't lower the salinity but I just don't know it so I'm hoping that someone can explain it to me.
 
ann83

ann83

Member
Yes. Definitely. Neomycin is hard on the kidneys, especially in high doses, which is why several of us have significantly reduced the dosage that is typically recommended by Noga to a dosage that is still high enough to be effective without creating resistant strains but is on the low end of the recommended range (according to fish disease books, at least).
However, while people used to recommend a lowered salinity for bacterial infections in the past, we mostly don't now, for a couple of reasons. First of all, it seems, from most of the reading that I've done, that when the kidney, gills, and intestines are involved in osmoregulation, the immune functions of those organs can be compromised, which is not something we want to do when the seahorse is already fighting off infection and already under quite a bit of stress. However, there is quite a bit of back and forth on which parts of the immune response are compromised, and when, and in what fishes, etc. So take it for what its worth, its just not a risk I want to take, especially since I don't have a thorough understanding of all of the enzymes and processes involved in the immune response.
Additionally, when you lower the salinity, you reduce the need for the seahorse to consume as much water (and, in normal circumstances, that would mean the kidneys would have to filter out less salt, which would be easier on them). During a bath treatment like what we're using with Neomcyin, the seahorse would also take in less of the antibiotic, requiring an increase of the antibiotic dosage, and therefore negating the expected benefit of the hyposalinity on the kidneys. Or, possibly, depending on the drug, causing the drug to stay in the fish's system longer, which could also be bad. Unfortunately, not a lot is known about the uptake of medications in fish, and most recommendations are just based on empirical evidence. I try to stick by the recommendations of Noga and others, who have gathered more evidence than I have myself; and Noga doesn't mention the use of hyposalinity for antibiotic treatment.
And finally, the bacterial lesion on the seahorse is an open wound. Changing salinity would therefore be highly inadvisable since open wounds are not osmoregulated.
So, that's my .02. For what it's worth, when it comes to fish, it wouldn't be a good idea to use hyposalinity for the treatment of edema either, since ultimately that would result in more fluid getting trapped within the tissues and thereby be harder on the kidneys.
 
ann83

ann83

Member
For what its worth, I don't think there is a problem with keeping your hospital tank around 1.020. But, I also don't think that qualifies as hyposalinity, and I don't think that you would see much of a benefit to the kidneys, nor much of a hinderance to the antibiotic at that level. Again, however, I would not do anything to change the salinity on a fish who has an open wound.
 
dive girl

dive girl

Member
Thanks for taking the time to answer Ann. I figured that you or Dan would have a rational. When I was weighing the pros and cons I didn't think about the wound. I was thinking also that the antibiotic would work better in something with a lower specific gravity too.
I've seen the Noga book and have considered buying it but right now I've got to set up yet another tank (my son's girl friend got me the cutest little H. comes for my birthday). I was really certain that when my husband said no more tanks he really meant it this time, but I think I've got him. I don't want to risk any of my horses by mixing species. Especially after all that I went through in April.
I have many books on seahorses including the Working Notes you recommended. Do you know of anything that is new? I know that Pete Giwojna is working on one but who knows when that will be available.
 
dive girl

dive girl

Member
I didn't think 1.020 would be considered hyposalinity either, that's why I tried to refer to it as a lowered salinity. I know that the oceans range in salinity with it being higher the closer you get to the equator.
I did my first fresh-water bath yesterday.... boy was I nervous. I think it was probably harder on me than on my comes. Are some of the parasites visible to the

[hr]
eye? I didn't see anything come off her but when I first got her and put her in QT on Tuesday, the small shrimp in there jumped all over her making me wonder if they were picking off parasites.
 
teresaq

teresaq

Active Member
She has a new baby. Very cute too.
H comes are pen raised and have to be treated as wild caught.
T
 
ann83

ann83

Member
Yes, some parasites are visible. Some are very easy to see, others it depends on how good your eyesight is. If she was twitching in the FW dip, that's a good sign that there were parasites coming off. I'd also go with an oral deworming regimen (3 weeks each of praziquantel, metronidazole, and fenbendazole); and I might even look into trying to obtain chloroquine if I were you, or at least figure out how you would obtain it if the need arises. Some of the net pen H. comes have some very difficult protozoan problems that the traditional medications won't do much for.
 
ann83

ann83

Member
Originally Posted by Dive Girl
http:///forum/post/3060882
I was thinking also that the antibiotic would work better in something with a lower specific gravity too.
It depends entirely on the antibiotic. Some antibiotics are absorbed better in higher salinity (like sulfas), while others are affected by pH or chelation and work better at lower salinity (like Baytril and tetracycline) because of their chemical reaction to the ions in salt.
 
dive girl

dive girl

Member
Originally Posted by meowzer
http:///forum/post/3060889
You have parasites???
Girl, you are tired!!
I was going to write that I didn't take a fresh-water bath, I performed one but then I thought, well I did shower.
I got bleeped!!! in the post above for saying a different word that means the same as 'your birthday suit'.
 
dive girl

dive girl

Member
Originally Posted by ann83
http:///forum/post/3060910
)... I might even look into trying to obtain chloroquine if I were you, or at least figure out how you would obtain it if the need arises.
The human drugs I can get, it was the animal medications (Baytril) that I had a hard time finding.
I'm going to my in-laws this weekend. I'll have to check the other site for the dosing information and may have to wait until I return. I should probably consider seeing if I can get her a friend so that I only have to go through all of this once, hopefully. I called my son this morning and expressed to him my pleasure in recieving such a sweet little gift but not to let his girlfriend do it again!! And, not to say anything to her unless she wants to buy me another living thing!!!
 
meowzer

meowzer

Moderator
Originally Posted by Dive Girl
http:///forum/post/3060914
Girl, you are tired!!
I was going to write that I didn't take a fresh-water bath, I performed one but then I thought, well I did shower.
I got bleeped!!! in the post above for saying a different word that means the same as 'your birthday suit'.


Now surely you knew I meant your horse
 
reefnutpa

reefnutpa

Member
FWIW... I keep all my seahorse tanks (fry, juvies, adults) at 1.020 all the time. Been doing that for years.
Tom
 
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