What types of bacterial diseases do koi carp get?

① Red-skin disease (hemorrhagic disease)

Symptoms: extensive hyperemia of the epidermis. There are no large ulcers or swellings on the body surface, only obvious redness at the fin bases, nostrils and other areas, with visible blood streaks. In the later stages it is accompanied by ascites and gill rot.

Pathogen and cause of infection: caused by Pseudomonas fluorescens, highly contagious. Unsanitary water, injuries, and spoiled feed can all cause this disease, and it occurs in all four seasons.

Treatment:

Soak the sick fish in the original tank (pond) with a 2 ppm furacilin solution, soaking for several consecutive days until the condition improves.

② Enteritis

Symptoms: loss of appetite, abnormal feces, generally white and trailing behind the fish; after the condition worsens, abdominal bloating and bleeding at the anus and fin bases appear.

Pathogen and cause of infection: caused by Aeromonas punctata. It is generally caused by koi eating unclean or spoiled feed.

Treatment:

In the original tank (pond), soak the sick fish in a 4 ppm furazolidone solution, or feed it feed containing garlic powder.

③ Bacterial gill rot disease

Symptoms: gill rot in koi occurs mostly in the juvenile stage. The gills of sick fish are often filled with mucus, and both the gill filaments and the gill cover epidermis show hyperemia; the gill filaments turn from red to white, gradually rot and carry debris, and finally the entire gill is affected. The sick fish shows difficulty breathing, the gills open and close rapidly, and it gasps at the surface, soon dying because it loses the ability to breathe.

Pathogen and cause of infection: caused by Flavobacterium columnare. It generally occurs when the water is unsanitary.

Treatment:

Place the koi in another container and soak the sick fish in a 2 ppm furacilin or potassium permanganate solution for 20-30 minutes, once a day for several consecutive days, until the condition improves.

Splash copper sulfate over the whole pond so that the copper sulfate concentration in the water reaches 0.7 ppm, splashing once a day for several consecutive days.

④ Tail rot and fin rot disease

Symptoms: the first type begins to rot from the fin edge and then extends inward; the second type begins to rot from the middle part of the fin and spreads in all directions. If the condition worsens, the skin of the whole fish becomes hyperemic, and if it is then infected with other pathogens, it can lead to death.

Pathogen and route of infection: the result of the combined action of Cytophaga columnaris and fungi. There are two routes of infection. First, because the stocking density is too high and the filtration function is not ideal, the fish's metabolic waste accumulates, causing pathogenic bacteria to multiply and infect the fish. Second, when new fish are introduced or the water is changed, differences in water quality or stress cause discomfort to the fish, making the surface mucous membrane secrete abnormally, and the fin edges become infected because they are thin and weak.

Treatment:

Clean the filter and add a little table salt to the (pond) tank, and at the same time stop feeding for several days.

In the original tank (pond), soak the sick fish in a 0.2 ppm potassium permanganate solution for several consecutive days until the condition improves.

⑤ Print disease

Symptoms: the disease first appears as red wounds like those from an injury, then circular or oval lesions appear on the epidermis, with hyperemia and swelling around them, shaped like a mark; as the wound worsens further, the muscles become inflamed and rot, and even the bones and internal organs may be exposed, making the fish very thin and weak, and in severe cases it can cause death.

Pathogen and cause of infection: caused by Aeromonas punctata. Unsanitary water and weak resistance of the fish can both cause this disease to occur.

Treatment:

Splash malachite green solution over the whole pond so that the malachite green solution concentration in the water reaches 1 ppm, splashing once a day.

In the original tank (pond), soak with 2 ppm furacilin for several consecutive days until the condition improves.

Mix furacilin or potassium permanganate with petroleum jelly and apply it to the affected areas of the sick fish.

Usually, the sick fish should be given extra nutrition to strengthen its resistance.

⑥ Perforation disease

Symptoms: the symptom of this disease is holes opening in the fish body, and the flesh inside rots and becomes hyperemic, as if scooped out with a spoon; one hole spans several scales. The affected areas are mostly on the sides of the body, the back, and the caudal peduncle. In severe cases, even the fish bones can be seen. Even if it heals, the regenerated scales will not be neat, thus reducing its ornamental value. When koi suffer from this disease, there is nothing unusual to be seen in their eating or swimming, but in the terminal stage the koi becomes listless and gradually moves close to the water inlet, and is also easily attacked by water mold.

Pathogen and cause of infection: caused by Cytophaga psychrophila, extremely contagious. The cause of perforation disease is long-term feeding of stale feed, or continuous feeding of highly nutritious feed at low water temperatures. This disease often occurs in early spring.

Treatment:

Place the koi in another container and bathe it in a 3% table salt solution for 5 minutes, once a day for several consecutive days, until the condition improves.

Place the koi in another container and bathe it in a 2 ppm potassium permanganate solution for 10-15 minutes, once a day.

Mix furacilin and petroleum jelly and apply it to the affected areas of the koi.