Acanthocephalan Infestations - Fish Diseases Caused by Parasites

Acanthocephalan Infestations

Acanthocephalans are “thorny- or spiny-headed” elongated (10 mm long) cylindrical worms, having an anterior refractile proboscis with hooks (Fig. 5-10).

CAUSATIVE AGENT:

Acanthocephalus, Pallisentis

SPECIES AFFECTED:

Snakehead, catfish, eel, tilapia, milkfish

GROSS SIGNS:

The parasite is attached to intestinal mucosa of the host. Affected fish have darkened, emaciated body.

EFFECTS ON HOST:

The parasite causes necrotic hemorrhagic ulcers in the intestine of the host. Growth retardation and mortality have been reported.

DIAGNOSIS:

Gross examination of intestine reveals elongated and sac-like worms with retractile proboscis armed with spines.

PREVENTION AND CONTROL:

•               Disinfect pond with quicklime

•               Control of water supply and potential intermediate hosts

•               Quarantine new and suspected stocks