Abstract: Objective To describe the growth and development of Schistosoma japonicum in goat and the intensity and tem? poral distribution of eggs excreted by goat feces，so as to provide baseline data for the control and elimination of the role of goat in the transmission of schistosomiasis. Methods The goat animal models of schistosomiasis were established，and stool sam? ples were collected for parasitological examinations. The number of adult worms recovered，variation of schistosomes in goat at different time points post?infection，number of eggs in schistosomes，variation in number and temporal profiles of eggs excreted from goat feces were observed. Results Of the 6 schistosome?infected goat，415 adult worms were recovered，with a mean adult worm recovery of 34.58%（range，23.00% to 45.50%）. Among the 5 goat infected with 200 cercariae each，47，93，77，74 and 73 adult worms were recovered 2，5，8，11 and 14 months post?infection，respectively. There were（200.00±42.33）， （226.20±45.88），（168.20±25.85），（183.80±55.13）and（190.80±53.53）eggs detected in female schistosomes. The mean pre? patent period of eggs excreted by 10 infected goat was（37.7±3.02）d. From 2 to 14 months post?infection，7 batches of goat fe? ces were hatched，and there were 30，23，14，1 and 2 times for miracidium intensity of“++++”，“+++”，“++”，“+”and“-”， respectively，with 42.86%，32.86%，20.00%，1.43% and 2.86% constituent ratios of miracidium intensity. Conclusions Ap? proximately 1/3 S. japonicum cercariae may develop to adults in goats post?infection，and the prepatent period of eggs is（37.7± 3.02）d. There is no remarkable decrease seen in the number of adult worms，eggs in female schistosomes and eggs in goat feces within 14 months post?infection. Our findings suggest a long duration for infected goat in the transmission of schistosomiasis，and there is no evidence to prove the“self?cure”phenomenon in goat，indicating that goat is an important source of infection for schistosomiasis japonica.

Key words: Schistosomiasis japonica；Schistosoma japonicum；Goat；Egg；Development；Prepatent period

摘要： 目的阐明日本血吸虫在山羊体内生长发育和虫卵随粪便排出的强度与时间分布，为控制和消除羊在血吸虫 病传播中的作用提供基础数据。方法建立山羊日本血吸虫病动物模型，采用定期收集粪便并进行粪便病原学检查，及 定期解剖等方法，分析比较山羊感染血吸虫尾蚴后成虫获得量、感染不同时间后羊体内血吸虫数量变化和虫体内含虫卵 数量，以及羊粪中血吸虫虫卵数量变化与时间分布特征。结果解剖6只血吸虫感染山羊，共检获成虫415条，平均每只 山羊成虫获得率为34.58%（23.00%～45.50%）。感染200条/只尾蚴的5只山羊在感染2、5 、8、11个月和14个月后分别获 得47、93、77、74条和73条成虫，感染8～14个月后获得的成虫数与之相近，未见明显减少；解剖所获雌虫体内含虫卵数 量分别为（200.00±42.33）、（226.20±45.88）、（168.20±25.85）、（183.80±55.13）个和（190.80±53.53）个，感染后2个月与14个 月雌虫体内血吸虫虫卵数差异无统计学意义（t = 0.301，P = 0.771）。10只羊感染血吸虫后排出虫卵的平均开放前期为 （37.70±3.02）d。羊感染血吸虫后2～14个月，共开展粪便孵化7批次，分别有30、23、14、1次和2次粪孵毛蚴密度为 “++++”、“+++”、“++”、“+”和“-”，孵化毛蚴密度分布构成比分别为42.86%、32.86%、20.00%、1.43%和2.86%。结论山 羊感染血吸虫后约有1/3的尾蚴可发育为成虫，虫卵开放前期为（37.70±3.02）d，感染血吸虫后14个月以内成虫数、雌虫 含虫卵数和粪便中虫卵数未见显著减少。本研究提示，感染性山羊在血吸虫病传播中的作用持续时间较长，且无“自愈” 证据，是日本血吸虫病重要的传染源。

关键词: 日本血吸虫病；日本血吸虫；山羊；虫卵；发育；开放前期