As Deinonych above says, "So, I don't really understand what your point is. If the goal is complete eradication, what difference does it make if FW dips are either partially effective or not effective at all? The point is that they will not completely eradicate the parasite, so why bother with them in the first place? With all due respect, this seems like splitting hairs. "
But, since folks wanted a bit more information on sources, here is one of several Google references: From
Adanced Aquarium Magazine (2004)
From Advanced Aquarium Magazine:
"Freshwater dips are largely ineffective in the treatment of Cryptocaryon irritans (Burgess, 1992). The host epidermis and thick layer of mucus form a barrier impervious to osmotic shock (Colorni, 1985). "Most of the trophonts whose hosts had undergone hyposalinity treatment, including freshwater, for at least 18 h, were still alive and occupied the same position in the host by the end of the experiment, following re-adaptation to sea water. They later dropped from the fish, encysted, and the tomonts produced tomites" (Colorni, 1985)"
And it goes on:
"Note that the above quote says "most" and not all trophonts. Trophonts embed themselves completely into the epithelium under a layer of skin. This protects these trophonts from dips. As the trophonts grow in size they gradually displace the overlying epithelium. This is when they become visible as white spots or nodules. Exposed trophonts may be susceptible to freshwater dips, but trophonts that survive continue in their life cycle making this method only partially effective at best.
Freshwater dips can cause osmotic shock. Typically the fish are exposed to the air during the process of capture, handling and transfer, all of which are stressful to the fish. Freshwater dips cannot be depended on as the sole method of treatment for Cryptocaryon irritans and can be counterproductive because they are highly stressful to the fish. They should only be used in combination with other treatments that will successfully interrupt the parasite's life cycle."
However, the source for the sticky (
advanced facts on Cryptocaryon Irritans) was taken from: Colorni, 1985 and later from Burgess, 1992.
Research on the subject for creating that reference was from Dr. Stephen Spotte's book
Captive Seawater Fishes: Science and Technology
Stephen Spotte, a marine scientist, was born and raised in West Virginia. He has been a field biologist for the U.S. Army Corps of Engineers Waterways Experiment Station (Vicksburg, Mississippi); curator and later director of Aquarium of Niagara Falls (New York); curator of the New York Aquarium and Osborn Laboratories of Marine Science (Brooklyn, New York); director of Mystic Aquarium (Mystic, Connecticut); executive director of Sea Research Foundation and research scientist at the Marine Sciences and Technology Center, University of Connecticut (Groton, Connecticut); principal investigator, Coral Reef Ecology Program (Turks and Caicos Islands, B.W.I.), and adjunct scientist at Mote Marine Laboratory (Sarasota, Florida). Dr. Spotte has a B.S. degree from Marshall University, a Ph.D. from the University of Southern Mississippi, and is author or coauthor of more than 80 scientific papers on marine biology, ocean chemistry and engineering, and aquaculture. Field research has encompassed much of the coastal U.S., Canadian Arctic, Bering Sea, West Indies, Indo-West Pacific, Central America, and the Amazon basin of Ecuador and Brazil. His popular articles about the sea have appeared in National Wildlife, On the Sound, Animal Kingdom, Explorers Journal, and Science Digest. Dr. Spotte has published 18 books, including three volumes of fiction, a memoir, and a work of cultural theory. He is a Certified Wildlife Biologist of The Wildlife Society and also holds a U.S. Merchant Marine officer's license.
But as I indicated above, if someone thinks freshwater dips are a good thing for cryptocaryon irritans, I say go for it. I don't recommend them for this particular parasite.
