[The development of Clonorchis sinensis in mice]

Freshwater fish were caught from Nenjiang River in Qiqihaer City, and examined for metacercariae of Clonorchis sinensis by the artificial digestion (pepsin-HCl) method. The metacercariae (35-40) were given orally into stomach to each Kunming mouse of infection group (50 mice). The mice in control group were given the same amount of normal saline. The mice were sacrificed on the 5th, 10th, 15th, 20th, 25th, and 30th day after infection. Worms were collected, fixed and stained with carmine acetate, and observed under microscope. The egg-laying capacity of C. sinensis was observed in mice. 96%(48/50) mice were infected with metacercariae of C. sinensis. The recovery rate of adult worms on the 5th, 10th, 15th, 20th, 25th, and 30th day post-infection was 42.1%, 52.6%, 63.2%, 62.2%, 63.3%, and 63.2%, respectively. The first appearance of eggs in utero and feces was on the 15th and 20th day after infection, respectively. The branch of testis in worms was observed after 20 days of infection.