【アクアリウム/熱帯魚の病気】薬浴をするとなぜ魚は回復するのか/その理由は？細菌感染と寄生虫症の場合について調べてみた/コリドラスは薬浴はイヤだけど死ぬよりましだから薬浴してくれって言ってました。

I've been wondering why medicated baths are effective when tropical fish get sick with bacteria and parasites, and I've been doing a lot of research to try to find an answer to this question. In my last two posts, I featured the columnaris and Aeromonas bacteria that recently infected my Corydoras, but in the end I wasn't able to figure out which bacteria he was infected with. By "not sure," I mean that I can't determine for sure what bacteria I have based on symptoms alone, but I gave him a medicated bath using a tropical fish medication that seems to be effective against infections caused by both bacteria. That's great, since it works against both possible bacterial infections. That's Elvage Ace, and its ingredients are sodium niflustyryl acetate, sodium niflustyryl acetate, niflustyrene. It's quite difficult to say, but I'm sure you'll remember it after repeating it so many times, but it's something like that, an antibacterial agent, and according to the website of the Livestock and Fisheries Safety Management Division, Consumer Affairs and Food Safety Bureau of the Ministry of Agriculture, Forestry and Fisheries, or rather a PDF titled "Regarding the Use of Fisheries Pharmaceuticals," sodium niflustyryl acetate is currently prohibited for use on most farmed fish species. I wonder why. Elvage, which contains sodium niflustyryl acetate, was apparently discontinued around 2013, but has since been reinstated for sale for ornamental fish. This may be related to the fact that sodium niflustyryl acetate cannot be used on most farmed fish species. After some research, I found that, following instructions from the Fisheries Agency, the production of sodium nifurstyrenate was banned in Japan as of March 31st, 2014. However, it was not banned from sale, and there were no restrictions on its use on ornamental fish. This is just a vague guess, but I can't help but think that sodium nifurstyrenate is highly toxic or something, so it shouldn't be used on edible fish. Just my imagination. So, what do you do if farmed freshwater fish contract Aeromonas or columnaris infections? The Ministry of Agriculture, Forestry and Fisheries PDF mentioned earlier lists the following as medications that can be used on farmed scorpionfish: For Aeromonas disease, the antibiotic oxolinic acid can be administered orally or fed to the fish. For columnaris disease, it recommends the use of the antibiotic sulfisozole sodium. The Cypriniformes mentioned here refers to carp, loaches, catfish, crucian carp, and other carp fish, but roughly speaking, strictly speaking, catfish are now classified as Siluriformes. Older information calls them Siluridae, though. Well, that's fine, but it seems that in aquaculture, drugs other than Elvage are used. I've been talking about antibacterial agents, and antibiotics are included in this category. They're all the same thing, but antibiotics are basically natural substances made by microorganisms, and can include processed versions of those, while some antibiotics are completely artificial. So, how do these antibacterial agents and antibiotics work on tropical fish? Or, more specifically, on the bacteria that cause infections? When I tried to research this, I found that although there are many ways to administer drugs, there isn't much information on how they work, so I decided to look into how they work in humans. Antibiotics are drugs that destroy bacteria or inhibit their growth, and they work by interfering with something in the bacterial structure or growth mechanism. For example, penicillin, a typical antibiotic, interferes with the synthesis of bacterial cell walls. This cell wall is the key point, and human cells do not have one. So, penicillin does not affect human cells and can only attack bacteria, which is interesting. This cell wall is a tough coating on the outside of the cell membrane, and is a structure found in plant, fungal, and bacterial cells, but does not exist in animal cells. This means that tropical fish, or rather fish in general, do not have cell walls, so by the same logic or reason, antibiotics should be effective when used to treat infections in tropical fish. So, in response to the question of how medications like Elvage Ace, which I used the other day, work on bacterial infections in tropical fish, the answer is that the antibacterial ingredients attack and destroy the bacterial cell walls, and since tropical fish don't have these cell walls, it seems that only the bacterial cells are affected. Somehow, I've arrived at this conclusion. However, like other medications, antibiotics can have side effects, and humans have experienced diarrhea, but this is because antibiotics attack not only pathogenic bacteria but also intestinal bacteria, commonly known as good bacteria. I don't know if tropical fish will get diarrhea, and this may be true for the tropical fish themselves, but when using medicated baths, it seems that they may also affect the so-called good bacteria in t...