ARGULUS
Argulus lice are obvious when they hit. They are greenish, disc shaped parasites that 'suck' onto the fins and sides of the fish. They can cause damage great enough to permit Ulcer formation. They do NOT respond well to Formalin. They DO respond very well, and very quickly to Organophosphates like Fenthion and also Dimilin. Argulus, also known as fish louse or fish lice, is a tiny parasite that posses a crustacean exoskeleton. It has two large circular suckers that it uses to attach to the skin of a Koi.
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| Koi With Argulus In Scales |
Argulus has a spike that is uses to poke a hole and feed on blood. Argulus is an egg layer, it will lay several hundred eggs on solid surfaces like rock. The eggs have a gestation period of about a month. Argulus take about a month and a half to grow out enough to be able to see. During this time, they will attack any fish or amphibians in the pond. Argulus, like any other parasite, can cause a secondary infection like Aeromonas. Be careful when holding a larger Argulus, it will use its spike to defend itself.
Lernea (Anchor Worm)
Lernea elegans, the most common type of Anchor worm affecting Koi, is a real threat. They attach ventrally, they hold on for about 14 days, and they reproduce copiously. The wounds they create almost always infect with Ulcer diseasse bacteria, Aeromonas, and then you have two problems. Treatment can be undertaken with Malathion, Fenthion, Trichloffon, Dylox, Dimilin, and SALT. Salt works by killing the freeswimming reproductive forms. Malathion just kills the Lernea dead, but is dangerous to the fish.
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| Koi With Anchor Worm In Scales |
Fenthion is slow but safer Dimilin is great if you can get it EPA and FDA will trounce you for having and using it. I do recommend removing any adults you see attached and swabbing the wounds with Iodine or mercurnchrome. I do recommend also feeding an antibiotic food when you see Lernea to head off problems.
Ichthyophthirius multifilis (Ich, White Spot)
Freshwater Ich causes small white spots all over the fishes body. In some cases, Ich spots may not be grossly visible, but you may see then under the scope. This has to do with a fishes' immune response or lack thereof. The disease is a ciliated protozooan , and it kills smaller fish, while sparing the larger ones. Damage to the gills is the primary way it kills. Its life cycle is roughly 2-5 days, but can be longer (5+ weeks) if the water is cool, much shorter if the water is warmer.
To treat, elevate water temps and add salt. Using salt rnay harm plants, so if you are looking for an alternative, I would use Formalin 37% and Malachite Green, applying 1cc Formalin 37% per 10 gallons water every 3rd day after a 30% waterchange. The Malachite green is not that important in this, but would be used to give the Formalin an emerald color. Overdosaing is unlikely with the Malachite fraction, used this way. Three or four treatments covering 10-14 days would be necessary. I always urge people to use salt first. Simply remove the plants and treat them outside the tank with Formalin 2cc per lOgal for 6 hrs before re-adding them to the system, to remove any latent Ich.
Trichodina
This saucer-shaped parasite is over-rated in its pathogenicity allthough, I have seen it cause spiderweb lesions in the skins of Koi. The most serious damage it may do is to the gills of smaller fishes. This is one of one of two or three parasites that causes scratching in Koi, with no serious side effects. The most important thing about Trichodina, is that when it is discovered, it belies a problem in the System Housekeeping department You can bet your license that there is some accumulation somewhere of mulm, and lots of it. TRICHODINA clears easily with SALT, and in very short order. You need only leave salt in for a few days to clear Tricho for good. Here again, if salt cannot or will not be used, Formalin is the next choice.
Gyrodactylus & Dactylogyrus (Skin and Gill Flukes)
Flukes, of the class Gyrodactylus and Dactylogyrus, have long been separated into Skin Flukes, and Gill flukes. There is no need. Because while there are even subdivisions within Gyrodactylus and Dactylogyrus, and they cam be distinguished by their eyespots and Hooks, and embryos; they all die the same. Flukes cause flashing in Koi and other species of fish, more than any other parasite. Rarely fatal to any but the smallest fish, Flukes eat slime and create bleeding microscopic wounds on the gills and skin of fish These wounds can, and often do become infected with Aeromonas bacteria, which is far worse than the original Fluke problem. Their lifespan is roughly 14 days, but they complete a reproductive-maturation cycle in 4 days, and they can be treated with Formalin 37%, Salt, Organophosphates, Droncit (Praziquantel) and Potassium recommend salt first, and if that has not cleared the problem, (as proven microscopically)then use Formalin as a clean up.Formalin as a clean up. Dactylogyrus has eyespots, Gyro does not. Gyro has an embryo inside, Dactylo does not.
Ichthyobodo Necatrix (Costia)
Ichthyobodo necatrix, also known as Costia, is a microscopic protozoan parasite. It causes great harm, it will even kill a Koi if left unchecked. Costia is the hardest parasite to see, for it is one of the smallest parasites that attack Koi. It has a very short life cycle, but it can still be active in cold water. Look for a group of swarming commas on the microscope slide. Costia, like any other parasite, can cause a secondary infection like Aeromonas.
RHABDOVIRVS CARPIO
was reported to be a primary pathogen of cyprinid species, particularly KoI and Carp. The virus causes what the British try to call Spring Viremia of Carp, which is the grossest misnomer; that tries to bundle a multifactorial process involving cold water, depressed immunity, opportunistic pathogenic bacteria, and then, only possibly, a virus like Rhabdovirus carpio; into a simple viral disease. Rhabdovirus carpio has several other names, as several scientists have found the same particle and given it different names. We do know that it can cause swim bladder inflamanation and a reddening disease of the skin called Carp Erythrodertnatitis. You should know that Rhabdovirus carpio, and Spring viremia of Carp, have not been isolated fom any fish on the North American continent, so before you cry VIRUS, read a little. Almost always, Aeromonas bacteria, (and a septicemia from same), are concurrent players witht this virus, and it is hotly debated whether Rhabdovirus carpio can even act alone.
CARP POX
is another virus of a dermatological nature, that also has a low transmissibility from fish to fish, and is again, not fatal, merely disfiguring. The lesions are soft and waxy, not warty and rough. The lesions should not be scraped. They may be differentiated from Lymphocystis because they do NOT cause the cells to become huge (megaloblastic) in size. The way Lymph does. There is no treatment, and lesions do not resolve as well as Lympho lesions do. You should be aware that CARPPOX lesions are very, very rare in North America.
LYMPHOCYSTIS
Of all the viruses affecting Kol, perhaps the most common is LYMPHOCYSTIS. This is a viral pathogen that is poorly transmissible between your specimens. It strikes fish when some damage has occurred to mouth or fin, and sometimes on the body. The lesions are warty and rough. They may be singular or numerous. I see this viral infection in fish in immaculate waters, and so I cannot verify that this is a stress related disease I do know that it is merely disfiguring, not fatal. Lesions may be scraped off; but this could open the skin or fin to bacterial invasion. The only lesions that should be addressed surgically are mouth lesions that interfere with eating. Often, the lesions clear spontaneously, usually, but not always, the SECOND summer after infection, at the peak of the heat. There is a commercial remedy sold for this, but it does not work, and is being sold purely to flim-flam the trusting hobbyist. It is merely acriflavine which is a useless dye.
Ulcer Disease
Ulcer Disease is almost always caused by Aeromonas bacteria or more rarely Pseudomonas bacteria clinically, I wouldn't know which because I rarely culture the pathogen. Why not? Because the results could take a week to return, and by that time, all the affected specimens would be dead. I have treated ulcer disease with the following drugs: Enrofloxacin, Chloramphenicol, Gentamicin, Amikacin, Tetracycline, and recently, Azactam. I inject these drugs. Suffice it to say, that to save these fish, my core recommendations would be to get the fish into a heated environment, provide impeccable water quality, swab the wounds with iodine or Mercurachrome, Feed Romet chow, Inject Enrofloxacin and or Chloramphenicol, and hope that the next spring that the fish does not bloat due to retention of latent bacteria in the kidney after clinical cure.
Scoliosis
Scoliosis is caused by a variety of conditions, none of which is infectious. The most common cause of scoliosis is Vitamin C deficiency. But there are 3 other causes. 2) Tryptophan deficiency: An amino acid protein building block that may be absent in foods due to improper formulation, hyper extended storage, excess heat in processing, or because no variation was permitted in the diet. To avoid this, always use two different high qualtiy staple diets, and supplement periodically with earthworms or other bait worms. Mealworms and crickets may also be accepted, especially if partially crushed. 3) Trauma: The muscles of Koi and other teleost fish are assorted in bands called 'somites'. When a somite is damaged, by intra Muscular injection technique, for example, or a sharp blow, the somite may die, which then shrinks, and kinks the fish, especially when swimming. It may straighten at rest. 4) Organophosphates, like Fenthion, Trichlorfon, or Malathion to name but a few, can cause kinking of the body due to hyper contraction of the muscles. (A side effect of these drugs on the fish is to prevent relaxtion of muscles) and this may kink, or break the fishes back.
Vitamin C deficiencies may be avoided by feeding a varied diet to include the following greens: Spinach, Turnip greens, Broccoli heads, and Dark leaf lettuce. NOT PLAIN LETTUCE!!! Additionally, store no food longer than 90 days, and be sure the label has added ASCORBIC acid. Once scoliosis is noted, the fish is better removed to fresh water, and better attention to diet is advised. As a side note, the biggest, fastest growing fish are most likely to kink, as they need the most Vitamin C and calcium in their diet, to support their rapid growth.
Saprolegnia
Fungal infections of Koi and other ornamental fish are usually caused by Saprnlegnia, a common, if not ubiquitous fingus. Other types include Achlya, Dermatocystidium1 and Branchiomyces. None of the fungal infections I have EVER diagnosed from Koi in 2 years of clinical practice have been anything other than Saprolegnia, and NEVER has Saprolegnia struck where there was not SOME sort of stressor. Surviving 'jumpers', (fish that have cleared the pond and flopped around), are always affected. Healing ulcers often become infected with fungus. The disease looks like cotton-wool protruding from the lesion, and may become stained with algae. Diagnosis is by microscopy, and this is important, as very often, Flexibacter columnaris will look just like this, and it will not respond to anti fungal agents, because IT is a bacteria! Treatment of fungal infections is only possible where immaculate water quality and good diet prevails. Then, a variety of drugs are effective, to include my favorite, Methylene Blue. Formalin is effective but only worsens stress on the fish. Malachite green can be swabbed on fungal lesions if the specimen can easily be captured daily. Potassium permanganate effectively kills fungi, perhaps better than anything, but this is a VERY dangerous drug to use on fish, unless you have great experience and don't mind a risk.
Dropsey/Bloater
Dropsy, also known as Bloater or Pinecone disease, is usually caused by bacterial invasion of the fishes' kidney. A herpes virus may also contribute. There is a sporozooan parasite that can damage the Kidney this way, called Mitraspora cyprini, but I have yet to see this on a necropsy. Dropsy is, for all intents and purposes, untreatable, based on 2 years experience, using the following drugs: Azactarn, Baytril, Chloramphenicol, Gentamicin, and Amikacin. I have tried a Sulfa drug, brand name Albon, and that did not resolve the problem either. Bacterial dropsy is usually caused by Aeromonas or Pseudomonas bacteria. I have also seen cases infected with Mycobacteria. By the time and the scales protrude form the body, the damage to the kidney is so profound that recovery is impossible. If you must try to save the fish, isolate the specimen, elevate temps while elevating oxygenation, and begin injecting antibiotics intraperitoneally. You could also feed the antibiotics in a medicated feed.
OODINIUM
Oodinium is the causative agent in Velvet disease. This pearshaped sessile organism gives a velvety, gold dust look to affected Kol. It is reported that this may not clear with Salt, but I have yet to see this type of resistance. If it didn'tclear with Salt, I would use Formalin. I have only encountered Velvet/Oodinium very rarely in Koi. It would be more common in freshwater aquariums or on recently purchased Goldfish.
CHILODINELLA
Chilodinella is one of the hottest fish killers there is. Under the scope you may see a beanshaped organism, or a large round organism full of tiny bubbles. Alive, the Chilodinella resembles a heart shaped onion with a flizzy end where you could imagine the onions roots would be. These are actually cilia. Dead, Chilodinella are motionless round balls full of tiny bubbles. They may resemble Ich but they do not have crescent nucleus nor do they move in their dead, rounded state. Chilodinella clears EASILY with salt. Leave the salt in for 14 days, and be sure to supplement aeration, as gill damage from Chilodinella may be severe in the survivors Chilodinella should be suspected anytime large numbers of fish are dying on the surface or who roll over on their sides except when disturbed, the Koi dash madly.
Reference:
1.Nishikigoi Info
2. Dr Eric Johnson DVM, AKCA Library
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