Control ulcer disease caused by aeromonas and pseudomonas bacteria in pond water
In stress situations koi and other pond fish become susceptible to attack by aeromonas and other pathological bacteria types that create ulcer disease
I am not qualified to discuss this subject in any detail. I would run the risk of causing rather than fixing problems if I said too much. In my small pond I have also never had a problem but then I never did:
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Introduce fish from the wild
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Introduce fish from ponds containing unhealthy fish
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Overpopulate my pond
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Throw in any chemicals of any kind
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Try to avoid using good biofiltration
There is however one area of technical development in recent years that is causing a revolution in koi keeping. This revolves around a product called Lymnozyme or Koizyme in the USA and called Genesyz in the UK.
Pond and pump troubleshooting guide
Costia Chilodinella parasites of gold fish and koi
Fish Health Bacterial Ulcer Disease Aeromonas and Pseudomonas
Fish health Dropsy or Pine Cone Disease
Gill Flukes Skin Flukes of gold fish and koi
How to Recognize and Treat basic Fish Health & Disease Problems
Ich parasites of gold fish and koi
Genesyz - Ulcer Disease And Dropsy - A New Perspective
This chapter is produced with permission of Chris Neaves, a well-known and respected South African Koi keeper. Chris wrote this article after discussion and agreement with myself. I used to sell Genesyz.
I am indebted to Tom Lansing of Phoenix, USA and Nigel Caddock of Nigishikigoi International for permission to reproduce text.
Ulcer disease has long being a scourge in the koi industry. We have always treated the symptoms, as we have never been in a position to treat the cause, safely and effectively until now.
Aeromonas bacteria or (more rarely) Pseudomonas bacteria almost always cause ulcer Disease and dropsy (pine cone disease).
Bacterial infections, caused by members of the genus Aeromonas, are among the most common and troublesome diseases of fish raised in ponds and re-circulating systems. Motile aeromonads are among the most abundant pathogenic bacteria found in fresh water aquatic environments. The wide spread distribution of these bacteria in the aquatic environment and the stress induced by intensive culture practices predisposes fish to infections.
Aeromonas bacteria causing various infections are called aeromonads. Whether acting alone or in mixed infections with other organisms, the motile aeromonads are responsible for significant financial losses annually. All species of fish, scaled and unscaled, are susceptible to infection. Under certain conditions mortalities can approach 100 percent. Interestingly enough Aeromonas infections also occur in other vertebrates, including frogs, turtles, alligators and, sometimes, humans.
Various species of Aeromonas such as A. hydrophila, A. sobria, A. caviae, and possibly other aeromonads, are capable of producing disease in fish. Numerous strains of these bacteria exist, and they vary greatly in their ability to cause disease. The marked genetic diversity among different aeromonad strains has made it difficult to develop effective vaccines.
Factors causing disease outbreaks
Aeromonads are capable of utilizing nutrients present in water and surviving for long periods in the absence of host fish. They occur in the greatest numbers in organically rich waters, such as those found in ponds and other aquaculture systems. These bacteria can also be isolated from the skin and intestinal tracts of healthy fish, from pond mud, aquatic plants and certain protozoan parasites.
Aeromonads are considered to be opportunistic pathogens, capable of producing disease only in weakened populations of fish or as secondary invaders in fish suffering from other diseases.
Environmental stress factors, particularly those associated with poor water quality conditions, enhance the development of disease. Heavy parasite burdens, overcrowding, high organic loads in the water, spawning activity, rough handling and transport also may lead to outbreaks of disease. Stress, such as oxygen depletion or cases of brown blood disease (caused by nitrite toxicity), often are followed by outbreaks of aeromonas infection within a short time.
Infections can occur in any age fish, but losses are usually most severe in fry and small fingerlings. Outbreaks are usually seasonal; with peaks in the spring to early summer and in the fall when water temperatures are between 18 to 30C. Spring out- breaks may be related to decreased disease resistance in fish that are in poor condition from over wintering or after spawning.
Signs of disease associated with aeromonas infection may be easily confused with other diseases. Infections vary greatly in appearance and may be seen in the skin only, as an internal systemic disease (septicaemia), or as a combination of both.
Outbreaks may be chronic (long-term) and affect only small numbers of fish or may produce acute (intense and short-term) infections accompanied by rapidly increasing, high mortality rates. There is often fraying and reddening of fins, accompanied by irregular, variably sized areas of de-pigmentation (paleness) that can develop anywhere on the body surface. The skin overlying these sites is eventually lost, exposing the muscle below. These open sores or ulcers may remain superficial or they can be extensive and invade deeply into muscle, revealing underlying bone in some cases
These ulcers often have ragged white margins bordered by a narrow zone of haemorrhage. Skin lesions can begin as small haemorrhages within scale pockets that can rapidly expand to larger areas. Affected scales are eventually lost and ulcers form.
Aeromonas infection may include the following external signs: exophthalmia (popeye), abdominal distension (swelling of the abdomen), and pale gills. Scales often accumulate oedema (fluid) in their pockets. This condition creates a roughened or bristled appearance. Skin lesions caused by aeromonads often have fungus or columnaris bacteria present. Fish affected only with skin lesions may continue to feed and survive for extended periods, despite the presence of severe ulceration.
Daily mortalities associated with this chronic form of disease may be low, but can rise to high levels over time.
The internal or septicaemic form of disease typically follows a more acute course with a sudden onset of relatively high mortalities. Affected fish usually do not eat and commonly will be seen swimming lazily near the waters surface or in shallow areas of a pond. If disturbed, the fish move into deeper water, but typically return to the surface within a short period of time. The internal organs may be enlarged, reddened or pale, or have a mottled pattern of deep red haemorrhage interspersed with pale areas of tissue destruction or necrosis
Organs with significant tissue necrosis become weak and are easily damaged when handled. The abdomen may be filled with clear, cloudy or bloody fluid. Highly virulent (deadly) strains may cause sudden mortalities with few external or internal signs of disease.
Mortality is strongly influenced by the general health status of the fish population, stress level, and virulence of the particular bacterial strain infecting the fish. Mortalities occasionally approach 100 percent in fry and small fingerlings.
The most common form of treatment is an antibiotic. Given internally by injection or simply added to the feed (if the fish are still feeding and an early diagnosis is made) or even in some extreme cases added directly to the pond. Treatment with medicated feeds will not be effective if a large portion of the fish population has already stopped feeding.
It should also be noted that the improper use of antibiotic feeds and injections has led to the emergence of aeromonad strains resistant to various drugs. It should also be noted that adding antibiotics directly to the pond water will kill the biofilter (now being called the bioconverter) and the beneficial bacteria in the pond.
A NEW IDEA WELL WORTH CONSIDERING
Every now and again something really worthwhile is invented for the fish industry. During the course of correspondence with koi keepers in America and the UK an unusual product was brought to my attention. We have become so used to treating anything suspect in the pond with chemicals that we no longer seem to know or care at the damage the use of chemicals does in the pond and to the healthy koi.
As koi are moved around they cannot help but come into contact with the nets that catch them and they cannot help but come into contact with other koi. I think we have all had the misfortune of loosing koi after new additions to the ponds.
We know that ulcers, lesions and dropsy are symptoms of internal and external bacterial infections in our Koi. While Ulcers are what we actually see, it is the Aeromonas bacteria that cause the problem in the first place.
We know that Aeromonas is common in all water. And we know that Aeromonas is an opportunistic bacterium that will infect our koi given the smallest opportunity.
We know that antibiotics generally work. We also know that overuse of antibiotics has resulted in bacteria mutating and becoming immune to that substance.
It would be a really good idea if we could strip the water of the bacteria causing the problems would it not? A sort of guided missile that only affects the chosen target. This would have been considered impossible in the past but according to tests (published here) Aeromonas can be safely eliminated from the pond.
A product has entered the market that does exactly this. Remarkably it contains no chemicals, no medications and no antibiotics of any kind. It is a proprietary, internationally patented organic preparation of non-pathogenic proprietary bacteria, enzymes and micronutrients. It works on the established principle of an accepted scientific process widely known in commercial livestock management called COMPETITIVE EXCLUSION.
Competitive Exclusion works in a remarkably simply way. If two species are perfect competitors, if they have the same competition coefficients, one of the two will become extinct. Competition theory states that perfect competitors cannot coexist and that in order to coexist, species must utilise resources differently and have different competition abilities.
With GENESYZ other harmless organisms are introduced into the pond that compete directly for the SAME food source the Aeromonas bacteria. As these bacteria are stronger competitors for the food source than the Aeromonas they literally consume all the food gram-negative pathogenic bacteria need to survive and grow.
Without a food source the Aeromonas bacteria are starved to death. While bacteria can develop resistances to chemicals and antibiotics they cant develop immunity to starvation.
The inventor of GENESYZ was Jim Keeton, president of Keeton Industries. Jim invented Genesyz in 1997 for use in food fish applications where the use of chemicals is prohibited. Tom Holder CEO of California based Koi Care Kennel had the stroke of genius to try it in his Koi pond and found to his amazement that the Aeromonas bacteria were eliminated.
The original trade name was Lymnozyme and the product is still sold in the USA under this brand name. Marketed as GENESYZ in South Africa and the UK or LYMNOZYME in the USA this product is designed to only compete with Aeromonas and not any nitrifying bacteria in the filter.
After using Genesyz the bacteria counts (CFU's) of these Aeromonas pathogens will then be reduced to such a low level that they will not have an affect on fish. It is impossible to completely remove the Aeromonas and Pseudomonas bacteria from the pond water.
Fortunately overdosing does no harm at all. So it is safe for koi keepers to use.
As a Koi enthusiast, first and foremost, the organic nature of Genesyz and its zero chemicals, zero medications nature renders it to offer significant fundamental appeal.
This web page is an extract from Tony Roocroft's "The Complete Pond Solver" ... you can read more about it at http://www.really-useful-books.com ... when you buy the book you get 12 Excel pond calculators free as well as "Water Lilies and Pond Aquatics" ebook also free.