Copepods are another group of parasitic crustaceans with a diversity of body forms with variable appendages. An example is
Lernaea species (anchor worm), which is an elongated copepod that embeds its head into the skin of fish, leaving its Y-shaped egg
sacs to hang from the fish. These sacs can easily be seen grossly. The anchor worm has a direct life cycle and lives in fresh
water.
 Figure13: Argulus species infestation on the caudal fins of a goldfish. The parasite has a flattened, saucer-shaped appearance.
|
Organophosphates are the typical treatment for parasitic crustacean infestations. Dichlorvos and trichlorfon are the most
commonly used organophosphates for treating fish with parasitic crustacean, monogenean, or leech infestation. Trichlorfon
(0.5 to 1 mg/L) as a prolonged immersion or dichlorvos (0.5 to 2 mg/L) as a 30-to 60-minute bath is effective.1,2 Diflubenzuron (Dimilin—PondCare) is a chitin synthesis inhibitor that when used at a dose of 0.01 mg/L as a prolonged immersion
treatment can also rid fish of crustacean copepod infestation.
Terry W. Campbell, MS, DVM, PhD Department of Clinical Sciences College of Veterinary Medicine and Biomedical Sciences Colorado State University Fort Collins, CO 80523
REFERENCES
1. Lewbart GA. Fish. In: Carpenter JW, ed. Exotic animal formulary. 3rd ed. St. Louis, Mo: Elsevier Saunders, 2005.
2. Noga EJ. Fish disease: diagnosis and treatment. Ames: Iowa State University Press, 2000.
3. Roberts RJ, Ellis AE. The anatomy and physiology of teleosts. In: Roberts RJ, ed. Fish pathology. Philadelphia, Pa: WB Saunders Co, 2001;12-54.
4. Groff JM, Zinkl JG. Hematology and clinical chemistry of cyprinid fish. Vet Clin North Am Exot Anim Pract 1999;2:741-776.
5. Lewbart GA. Medical management of disorders of freshwater fish. Compend Contin Educ Pract Vet 1991;13:969-974.
6. Whitaker BR. Common disorders of marine fish. Compend Contin Educ Pract Vet 1991;13:960-967.
7. Gratzek JB. The science of fish health and management (aquariology series). Morris Plains, NJ: Tetra Press, 1992.
8. McAllister PE. Goldfish, koi, and carp viruses. In: Stoskopf MK, ed. Fish medicine. Philadelphia, Pa: WB Saunders Co, 1993;478-486.
9. Hedrick RP, Gilad O, Yun S, et al. A herpesvirus associated with mass mortality of juvenile and adult koi, a strain of common
carp. J Aquatic Anim Health 2000;12:44-57.
10. Tucker CS. Water analysis. In: Stoskopf MK, ed. Fish medicine. Philadelphia, Pa: WB Saunders Co, 1993;166-197.
11. Moe MA. The marine aquarium reference: systems and invertebrates. Plantation, Fla: Green Turtle Publications, 1992.
|