The development of the nematode Procamallanus saccobranchi Karve, 1952, a parasite in the stomach of the fish Heteropneustes fossilis (Bloch), was studied in Mesocyclops crassus (Fischer) and Mesocyclops leuckarti (Claus). After being ingested by the copepods the nematode first-stage larvae penetrated into the haemocoel of the intermediate host; there they moulted twice (on days 3 and 5 p.i. at 28-30°C) attaining the third, infective stage. The definitive host H. fossilis acquired infection by feeding on copepods harbouring infcclivc-stage larvae; in the stomach of this definitive host, the larvae were observed to undergo two more moults. The third moult occurred on day 13 p.i. and the fourth moult on day 38 p.i. and day 66 p.i. in “male” and “female” larvae, respectively. The larval stages, including the moulting forms are described and illustrated.
Larval development of the nematode Onchocamallanus bagarii (Karve et Naik, 1951), recovered from the intestine of the fish Bagarius bagarius (Hamilton) was studied under laboratory conditions. The cyclopoid copepods Mesocyclops leuckarti (Claus) and M. crassus (Fischer) were infected with first-stage larvae from female uteri and maintained at temperatures 29-30°C. After being swallowed by the copepods, first-stage larvae burrow through the intestinal wall and reach the haemocoel of the copepods and there they grow and moult twice to attain the third and infective-stage. First-stage larvae become ensheathed after 65 hours of infection and second-stage larvae first appeared on day 3 post infection (p.i.). The second moult occurred on day 5 p.i. The larval stages occurring during development are described.
The developmental stages and life cycle of the nematode Camallanus anabantis Pcarse, 1933 an intestinal parasite of Anabas testudineus (Bloch) arc described. The copepod Mesocyclops leuckarti (Claus) was used as experimental intermediate host. After being ingested by the copepods the nematode first-stage larvae enter its haemocoel, where they moult twice, 4 d.p.i. and 11 d.p.i., at 21-26°C, respectively to become the infective third-stage larvae. The definitive fish hosts become infected when feeding on copcpods harbouring infective larvae. In the fish host’s intestine the larvae undergo two more moults, the third on day 15 p.i. The fourth moult of “male” larvae occurred on day 68 p.i. and that of “female” larvae on day 86 pi. at water temperatures 24-36°C- A female with eggs and few larvae in the uteri was first observed on day 187 p.i.