Hi Doc,

I am injecting some sick koi, supported by my vet who is new to koi. I've had mixed results with Baytril so I'd like to try Amikacin. The basic dosage in your book is given at 5 mg/kg, but the dosage by length in your chart appears to give 20 - 25 mg/kg. Isn't this a major difference? What is your reference for the dosage by weight. please?

Answer:

Major difference - sort of. (Maybe this is why Gentamycin was so poor in my hands)

First, the 5mg/kg dose is from mammallian work. There was no fish dose when I started. The dosing chart is from what I was actually doing with fish at the time.

Because there were unproven mammallian doses, juxtaposed with "what I was getting away with" at the time, I presented both in the book, so if a person thought better of dosing using cat and dog dosing, they could do that on a "weigh the fish" basis, which is fine, but no one had actually proven that fish could get by on 5mg/kg

Or, they could use the dosing chart which I used successfully for a couple years before publishing that chart. I had very few problems.

Still, I *would* add that if you dose Amikacin (any Aminoglycoside) more than three times, you could kill or cripple the fish. I really, really dislike Amikacin compared to Azactam and the rest.

I think I am going to re-do the Amikacin dosing chart, using ACTUAL weights (what a pain), and basing it on 10mg/kg - for what it's worth.