"Ich" = White Spots?
for the week of 4/30/98
Over the past few months, I've spent a fair amount of time at the microscope, trying to get a better feel for which parasitic infections are common, as well as which medications are effective. I've learned quite a bit during this time, including:
- Many common parasites are fairly easy to identify microscopically, once you get the hang of it.
- Flukes are much more common - and ugly - than I'd have guessed.
- Many fish have a few parasites, but sick fish have many.
But one of my more striking discoveries was that fish can be heavily infested with "Ich" (Ichthyophthirius multifiliis) without showing the little white spots so commonly associated with it. I've seen quite a few fish both from our tanks and those brought in by customers for diagnosis that were obviously ill, but didn't have the "little white bubbles," "pimples" or "grain of salt sized spots" usually seen when "Ich" is present. Most of these fish appeared "slimier" than normal, even to the point that the mucous had begun to slough off. In some cases, the skin had also been damaged in places, and a reddish tinge (possibly caused by a secondary bacteria infection) appeared in the underlying flesh. In almost all cases, the fish were listless and breathed with difficulty.
Examining a bit of skin mucous under the microscope revealed that the fish was literally crawling with "Ich" parasites. Dozens or maybe hundreds, in various stages of development, could be seen in a small scraping from the fish's flank.
Fortunately, "Ich" is very easy to eliminate, most commonly with a couple of days' treatment with a good quality malachite green preparation, or sometimes even with a heavy salt bath. And I should point out that had I not used the microscope, I probably would have treated with a broad spectrum parasite drug that coincidentally would have also cured "Ich" anyway. But I can't help but wonder how often fish are lost because this easy-to-treat disease isn't suspected because it doesn't always show its classic signs.
Submitted by: Jim Kostich
"Tip of the week" appeared regularly in 1999 and 2000.
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