잉어에 寄生한 寸蟲, Bothriocephalus opsariichthydis의 生活史에 關한 硏究

Life History of Bothriocephalus opsariichthydis(Cestoda; pseudophyllidea) Parasitic in Common Carp, Cyprinus carpio(Linne)

In Korea, lots of Israeli carp (Cyprinus carpio) are cultured by means of net cages in dams and lakes, but many carp have been subjected to heavy infestation of the cestoid, Bothriocephalus opsariichthydis. Nevertheless the parasitic state and life history of the cestoid are not yet reported. This reason led the author to study the parasitic state and life history of B. opsariichthydis parasitized in the carp in order to take effective control measures against its damage. Israeli carp were sampled from two fish farms, in Taech'on and Kyongch'on. After dissection of the specimens, the cestoid were obtained and the parasitic rates were examined. After taking the eggs from adult worms, the development of the eggs were observed. Coracidia were exposed to four kinds of crustaceans in order to investigate the infection rate and development of the larva. Finally, the development of the larva in the final host was investigated. The fully mature eggs were in the cleavage stage, when they are released, and the size ranged 47.5 to 55.0(50.9) X 30.0 to 32.5 (31.1)um, in the state of under-developed coracidia and blastomeres. The parasitic rate of the cestoid in Israeli carp from Taechon was 55.5% in 1984 and 21.6% in 1985, that from Kyongchon was 64.7% in 1984, and color carp from Kusan was 14.9% in 1984. The eggs were hatched to coracidia within 48 hours under 26 to 28℃. The cestoid showed a strong affinity to Thermocyclops hyalinus and Paracyclops fimbriatus and the infection rates were 93.5% and 75.5%, respectively. At 14 days after the infection to Thermocyclops hyalinus and Paracyclops fimbriatus, the larvae of the cestoid grew into fully developed procercoids; 207 to 225(214)X90 to 102(84) um in size. Sixty days after carp have ingested the Thermocyclops hyclinus infected with the fully developed procercolds, the larvae of the cestoid matured into adult worms in the intestines of the carp.