Medicating fish

Discussion in 'Freshwater Fish Disease' started by Jaysee, Dec 5, 2012.

  1. JayseeFishlore LegendMember

    I was watching a documentary the other day on fish management. They wanted to be able to track the stocked fish they introduced, so in order to differentiate them from the native population they marked the fish. They went into a high salinity salt bath until they turn belly up, then they are removed and washed off, then placed into another container that contained a special dye. They explained how the salt water dehydrates the fish, that way when the fish is placed into the bucket with the dye, it absorbs the water, and the dye. The dye stains the bones of the fish, that way they can be identified with a light.

    SO, why wouldn't this principle work with medications? Give the fish a salt bath before administering the medication. Of course this would be geared towards a more serious problem - not something that's caught early. I suppose there would be a risk of an overdose due to the possible increased uptake. But, if your fish is in such dire straights that you are considering this, that's a risk you'd probably be willing to take.

  2. backflipfronflipWell Known MemberMember

    An interesting take on that method. I would be nervous trialing the technique though.
  3. CichlidnutFishlore VIPMember

    Did they talk about the mortality rate of marking the fish?
  4. JayseeFishlore LegendMember

    Yes, they said almost all of them survive. Wouldn't make much sense to do something that killed the fish that they were trying to track....
  5. CichlidnutFishlore VIPMember

    Well, I'd like to know exactly how they did it. Doesn't seem to be all that unreasonable to me though.
  6. JayseeFishlore LegendMember

    How they did what?
  7. CichlidnutFishlore VIPMember

    I want to know the specific gravity of the solution they used and the duration they kept the fish in there. Also, what kind of salt did they use?
  8. chevyguy8893Well Known MemberMember

    That is an interesting use of the fish's osmoregulation. I do believe it would aid in the uptake of medications in the fish. If I remember correctly it has been found that adding aquarium salt for freshwater fish does help the effectiveness of the medication, this may be why.

    So, pretty much the same as the dye, if a freshwater fish is put in a saltwater bath, or dip, using aquarium salt the cells would be purged of water and pull in more salt till the fish goes belly up. Then, moving that fish back into its normal freshwater environment purges the salt from the bath and pulls in the surrounding water that would have the medication. As a last resort it would probably be helpful, but the amount of stress caused may just make things worse. Since this would cause the slime coat to be stripped I would think dosing prime or something similar would help with that.

    The only time this really wouldn't make a difference if it was a bacteria or parasite that has a resistance to the medication. It is pretty neat how quick bacteria can build up a resistance if a treatment doesn't kill them all off (not good in an aquarium or elsewhere, but in a lab setting it is neat :)).
  9. JayseeFishlore LegendMember

    There was no mention of the salinity other than "high". The fish were noticeably affected immediately. I'm not sure how long the salt bath was for, but the fish looked like they were pushed to the brink. I'm reaching, but I think the whole process may have only taken 10-15 minutes, so maybe 5 minutes in the salt?
  10. CichlidnutFishlore VIPMember

    I'd want specifics before I would try it. You can do it and log your experience. :)
  11. JayseeFishlore LegendMember

    I'd need a suitably sick fish, that I cared about treating. I am absolutely going to try it if such a situation presents itself.
  12. chevyguy8893Well Known MemberMember

    What seems to be a normal treatment for a salt bath is a 3% solution with aquarium salt for a half hour. The higher the salt content the less time it would take for the fish to go belly up, but the less room for error.
  13. jetajockeyFishlore VIPMember

    I'm guessing it's similar to the salt dips that they do in the big aquariums to new arrivals. Would be nice to get more hard data on these procedures to help in the QT process.
  14. chevyguy8893Well Known MemberMember

    Has anyone tried searching to see if they have a journal article published on this? It would go into far more detail than a documentary. I did a brief search and found some articles, but I haven't had a chance to read them.
  15. carolo43Valued MemberMember

    Kinda confusing to me. Salt retains water and why Epsom Salt is used for constipation, bloat, etc. (Salt retains water also in humans.) Are you sure they did not use Epsom Salt? Epsom removed fluids, salt retains.
  16. JayseeFishlore LegendMember

    I don't know what kind of salt it was. But, salt retains...when it's inside the body. It dehydrates when it's outside (like in the water).
  17. chevyguy8893Well Known MemberMember

    So I found a journal article that ran experiments similar to this "Development and Evaluation of Methods for Osmotic Induction Marking of Golden Perch Macquaria ambigua with Calcein and Alizarin Red S". For this particular experiment "A 5% salt solution was prepared by dissolving 100 g of commercially available natural salt (source: Lake Charm, Victoria) in 2 L of aquarium water". They did tests at 5 and 10 minute baths of a salt and dye solution, then observed growth, mortality rates, and other induced stresses. This, and other experiments I found, found a lower mortality rate as compared to long (a day or more) immersion in a dye solution in the aquarium water.

    That article follows the same hypothesis proposed by the documentary without the second dip to absorb the dye because of the osmotic change. So, if this is applied to an uptake of medication, I believe it would not really matter what type of salt is used (as long as it is safe for fish) the result is going to be the same. The fish's natural adaption to the increased ions in the water is going to cause a change in the osmotic pressure in the fish in order to become balanced with the surroundings.

    - David A. Crook, Damien J. O'Mahony, Andrew C. Sanger, Andrew R. Munro, Bronwyn M. Gillanders & Stephen Thurstan (2009): Development and Evaluation of Methods for Osmotic Induction Marking of Golden Perch Macquaria ambigua with Calcein and Alizarin Red S, North American Journal of Fisheries Management, 29:2, 279-287

    Search "osmotic induction marking" on google and google scholar to see if there is anything else. Here is a link to another article that doesn't require permission for access.

    Edit: One thought I had, would it be possible that a negative reaction to the medication could occur due the the increased rate of the uptake?
    Last edited: Dec 6, 2012
  18. carolo43Valued MemberMember

    OHHHHH.....never thought of that! :;hug2 LOL
    Wonder how it works on constipation. Not LOL
  19. CichlidnutFishlore VIPMember

    Epsom salt baths are supposed to help with constipation.
  20. JayseeFishlore LegendMember

    I thought constipation was a matter of not enough water...