Argulus – Also known as fish lice/freshwater louse Argulus Foliaceus

What is argulus?

Argulus is a parasite which can and will affect the entirety of your livestock if an infestation occurs.

Argulus can cause an illness called “argulosis.”

This disease can cause poor health in the following ways:

  • Stunted growth
  • Underweight fish or fish unexpectedly losing weight.
  • Vanaemia
  • Death

The argulus are parasitic at all stages of development, from newborn to adulthood. This louse will attach itself to your fish using its suction cups and pierces through the skin to feed on the blood of your fish. This parasite not only lies on the skin of your fish, but it has been known to live within the gills.

A large infestation can cause:

  • Inflammation of the skin
  • Openly bleeding sores
  • Large overproduction of mucous
  • Scale loss
  • Corrosion of fins

The wounds are often infected with additional ailments as argulus act a host for additional pathogens of a bacterial, fungal, and viral nature.

To find a host the fish louse uses three of its senses. Vision, smell, and touch. During the day, with light available, the search for a host is done visually whilst the argulus lies in wait, ready to ambush when a suitable host has been located. However, in the dark, the louse swims freely and actively searches using its sense of smell and uses the movements it can feel in the water to find the ideal host.

The swimming and searching stage becomes more driven the longer the louse has left since its last feed. This is more obvious after a twenty-four hour period has passed, and the louse search becomes more determined.

During the reproduction cycle, the male and female louse will actively mate on your fish, after the mating has been completed the female will leave the host to lay eggs on the bottom of your pond. This is because the female prefers to lay eggs on a hard, solid surface. The female can lay up to five hundred eggs in one breeding session. They also tend to lay more eggs during the day and less at night.

Once the eggs hatch, the newborn lice are infectious right from birth. However, the louse will shed and grow eleven times prior to reaching adulthood. The young have a hooked antenna as opposed to the suction cups the adults possess, which they use to latch onto the host in order to feed. Once the young have fully developed into adults the cycle begins again with each female having the ability to produce up to five hundred eggs!

Treatment is required as soon as the infection is apparent to help preserve the health and livelihood of your livestock!

Identifying and diagnosing fish lice!

As with most illnesses spotting the first changes in behaviour and acting immediately is vital. A few of the behavioural change that may be observed are:

  • Stunted growth
  • Weight loss
  • Loss of appetite
  • Erratic swimming
  • Rubbing
  • Flashing
  • Stress
  • Death

Alongside these symptoms, adult argulus are visible to the naked eye. This is when they are present on both the host and when they are swimming freely in the water.

Argulus have a disc shaped, jelly consistency appearance, the colour of these lice can vary from green to brown, and they may appear to be see through too.

If you cannot visibly see the lice, this may mean that they have not reached the adult stage and are still progressing through infancy. A mucous scrape will be required for a diagnosis.

If you are in doubt, then please give us a call and arrange a call out as soon as possible. During the call out a scrape will be performed and analysed under the microscope for the most accurate diagnosis.

Please note that the symptoms may not always be true to an argulus infestation. They are merely indicating that your fish are in distress and require treatment.

Do not delay call the pond medic today. Tel:07737 674417

Causes

Argulus can be triggered in times of stress, where your fish has a compromised immune system.

The parasite is normally introduced to your pond from an already infected fish being added to your established livestock, if you are purchasing a fish from an aquatics store and you see they have argulus, then please do not take the fish from the infected tanks to your pond.

In some cases, the parasite can be introduced to your pond from toads and frogs that are frequenting your pond.

How contagious is argulus?

EXTREMELY

Given the life cycle of the parasite and the communicability the whole pond requires treatment. Not just the fish who have been identified with the disease.

Treatment

The water quality of the pond will require balancing. This will reduce stress and improve the living conditions for the fish, in turn this will help to boost the natural immune system of the fish.

If possible, raising the temperature of the pond is advised. This will increase the vulnerability of the parasite and make it more receptive to the treatment.

The treatment will take multiple doses to be 100% effective.

Being vigilant with the dose and timings of the doses is paramount to ensure the treatment is successful. This is due to the lifecycle and reproduction rate of the parasite.

Keeping to the treatment plan is vital to restore health to your pond.

Prevention

There are a few steps that can be taken to help to prevent any possible outbreaks.

  • Attain and maintain optimum water quality and pond conditions for the fish.
  • Monitor the pond temperature.

  • Ensure the fish are fed an excellent quality food to make sure they are getting the correct level of nutrition.

  • Try not to introduce too many fish at once.
  • Do not overpopulate the pond.
  • Monitor the water quality on a regular basis and filter the pond with the correct filter for the size of your pond, if possible one that contains activated carbon.

If you are unsure about your water quality and filter system, please the pond medic for advice. 07737 674417