Definition

1. Noun:
   • A fatal disease of freshwater fish: "Costiasis" refers specifically to a serious and often lethal parasitic infection affecting freshwater fish species.
   • Caused by a flagellated protozoan: The disease is caused by a microscopic, single-celled parasite called Costia necatrix (also classified as Ichthyobodo necator), which is a type of flagellate protozoan.
   • Characterized by skin invasion: The primary pathology involves the parasite invading and feeding on the skin and gills of the fish.

Usage Examples

• Noun:
  • The outbreak of costiasis in the farm wiped out the entire stock of trout.
  • Aquarists must quarantine new fish to prevent the introduction of costiasis.
  • Symptoms of costiasis include lethargy, flashing, and a milky mucous coating on the skin.

Advanced Usage

• "to diagnose costiasis": to identify the disease through microscopic examination.
  • The veterinarian was able to diagnose costiasis by observing the parasites under a microscope.
• "an outbreak of costiasis": a sudden occurrence of the disease in a population of fish.
  • The fishery suffered significant losses due to an outbreak of costiasis.

Variants and Related Words

• Costia (n): The genus name of the protozoan parasite responsible for the disease.
  • The slide showed a high concentration of Costia on the fish's gills.
• Ichthyobodosis (n): An alternative technical name for the same disease.
  • Ichthyobodosis is another term used in scientific literature for costiasis.

Synonyms

• Ichthyobodosis: The synonymous scientific term for the disease.
• Fish parasite infection: A general descriptive term, though less specific.

Related Phrases

• To treat for costiasis: To administer medication, often formalin or copper-based treatments, to eliminate the parasite.
  • The pond was treated for costiasis with a recommended parasiticide.
• Susceptible to costiasis: Describing fish that are vulnerable to contracting the disease, often due to stress or poor water conditions.
  • Fish with compromised immune systems are highly susceptible to costiasis.

Related Terminology

• Ectoparasite (n): A parasite that lives on the external surface of a host. is an ectoparasite.
  • Costiasis is caused by a harmful ectoparasite.
• Freshwater aquaculture: The farming of freshwater fish, where costiasis is a known health concern.
  • Managing water quality is crucial in freshwater aquaculture to prevent diseases like costiasis.

Noun

1. a fatal disease of freshwater fish caused by a flagellated protozoan invading the skin