Ichthyophthirius multifiliis facts for kids
Ichthyophthirius multifiliis, often called "ich" or "white spot disease," is a common illness that affects freshwater fish. It causes tiny white spots to appear on the fish's skin. This disease is caused by a very small living thing called a parasite.
Ich can affect many types of fish. This includes pet fish in tanks and ponds. It also affects fish raised on farms for food. Even wild fish living in rivers and lakes can get this parasite.
Contents
Life cycle of Ich
The life cycle of the I. multifiliis parasite depends on the water temperature. In warm water, around 25 °C (77 °F), the parasite's whole life cycle can be very fast. It might take only about seven days from start to finish.
However, in colder water, like 6 °C (43 °F), the life cycle slows down a lot. It can take much longer, sometimes up to eight weeks. This means the parasite grows and reproduces more slowly in cold conditions.
How Ich affects fish
The disease starts when the tiny parasite digs into the fish's skin. This causes the fish's body to react. It often leads to swelling and the white spots you can see. These spots are a key sign of ich.
After a few days, the parasite changes. It becomes a jelly-like blob called a trophozoite. This blob then falls off the fish. It settles down on the bottom of the tank or pond.
Inside this jelly blob, hundreds of tiny baby parasites grow. These babies are called tomites. Eventually, these tomites can swim on their own. They then search for another fish to attach to and start the cycle again.
Sometimes, fish can have the ich parasite without showing any visible spots. Fish owners need to be careful about where they get new fish. The disease can spread very easily from one fish to another.
Signs a fish has Ich
Fish that have ich might show several signs. It is important to watch your fish closely. Here are some common things you might notice:
- They might stop eating their food.
- They could start losing weight.
- Their breathing might become very fast.
- They may try to hide more than usual.
- They might rest on the bottom of the tank a lot.
- They could rub or scratch themselves against objects.
Treating Ich in fish
There are different ways to try and get rid of the ich parasite. The best treatment depends on the type of fish. It also depends on how bad the infection is.
One method is to warm up the water. Heating the water can help kill the parasites. This works before they can infect more fish. Another way is to add salt to the water. You can also give the fish a short salt water bath.
It is important to change the water often. This helps remove parasites that have fallen off the fish. Special chemicals are also available. These chemicals are made to kill Ichthyophthirius multifiliis. Always make sure to plan treatments carefully. Different fish species need different care.
Images for kids
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Trophonts of Ichthyophthirius multifiliis (diameter 300 μm) in the epidermis of a rainbow trout tail fin (light microscopy with subillumination). The horseshoe-shaped macronucleus is visible. (photo: Kurt Buchman, University of Copenhagen)
See also
In Spanish: Ichthyophthirius multifiliis para niños
