目的:通过人工方法将湖北钉螺制备成血吸虫感染性钉螺,确定钉螺感染的最佳条件,建立钉螺人工感染传代的室内株,为研究其感染活性、遗传变异和疫苗等提供实验室依据.方法:用尼龙绢筛集卵法收集日本血吸虫成熟虫卵,常规法孵化毛蚴.将钉螺与毛蚴按不同比例进行感染,感染方式分为个体感染和集体感染.个体感染随机分6组(Ⅰ～Ⅵ组),每组200只钉螺,每只钉螺置单孔内分别感染,钉螺感染毛蚴比例分别为1:0,1:5,1:10,1:15,1:20,1:25;集体感染随机分6组(Ⅶ～Ⅻ组),每组200只钉螺,按组别集中感染,Ⅶ～Ⅻ组钉螺感染毛蚴比例分别同Ⅰ～Ⅵ组.然后对每组钉螺的感染数、死亡数及尾蚴逸出量进行比较,确定最佳感染方法和比例.以第1代人工感染性钉螺逸出的尾蚴感染实验动物,获取成熟虫卵并孵化毛蚴,然后采用个体感染方式,以1:15的比例继续感染钉螺,获得第2代人工感染性钉螺.比较第1代与第2代人工感染性钉螺的感染数、死亡数及尾蚴逸出数.通过动物感染实验,比较人工第1代、第2代感染性钉螺与自然感染性钉螺日本血吸虫成虫发育率、每克粪卵数(fecal eggs per gram, FEPG)及每克肝卵数(liver eggs per gram, LEPG). 结果:个体感染Ⅰ～Ⅵ组的钉螺感染数分别为0±0,22.7±4.2,31.7±4.5,53.0±5.3,39.3±5.9,32.7±4.7;钉螺死亡数分别为21.7±3.1,25.0±3.6,31.3±4.9,44.7±6.5,78.3±9.5,89.7±13.6;钉螺平均逸蚴量为0±0,308.0±96.6,428.1±146.2,527.0±171.1,571.4±148.9,602.9±356.3.集体感染Ⅶ～Ⅻ组,钉螺感染数分别为0±0,12.3±2.5,18.7±4.7,28.3±4.2,33.3±4.7,29.3±5.5;钉螺死亡数分别为22.7±3.8,23.7±4.5,28.3±5.5,47.0±9.5,75.7±8.5,86.3±12.2;钉螺平均逸蚴量为0±0,244.5±57.3,292.3±74.8,347.1±100.8,477.2±142.1,447.3±161.4.用人工制备的第1代感染性钉螺对血吸虫进行人工传代研究,成功获得了人工第2代感染性钉螺,感染率为24.65%,钉螺死亡率为24.50%;与人工第1代钉螺26.65%的感染率及22.35%的死亡率差异均无统计学意义(P>0.05).在尾蚴感染动物试验中,人工第1代、第2代感染性钉螺与自然感染性钉螺的成虫发育率分别为68.50%,73.50%,71.00%,3组间差异无统计学意义(P>0.05);自然感染性钉螺和人工第1代、第2代感染性钉螺的FEPG分别为1 503±269,1 683±233,1 541±117;LEPG分别为6 641±1 819,6 272±1 419,7 263±1 643,3组间比较差异无统计学意义(P>0.05). 结论:通过用人工感染的方法可以获得日本血吸虫感染性钉螺.个体感染方式优于集体感染方式,感染时钉螺与毛蚴的最佳比例为1:15.人工感染性钉螺经传代后,第1代与第2代钉螺在感染数、死亡数及尾蚴逸出数等方面无明显差别.比较人工第1代、第2代感染性钉螺与自然感染性钉螺的成虫发育率、FEPG及LEPG,差异也无统计学意义,证明人工传代的血吸虫尾蚴(室内株)能达到自然野生株尾蚴的感染效果.
目的:通過人工方法將湖北釘螺製備成血吸蟲感染性釘螺,確定釘螺感染的最佳條件,建立釘螺人工感染傳代的室內株,為研究其感染活性、遺傳變異和疫苗等提供實驗室依據.方法:用尼龍絹篩集卵法收集日本血吸蟲成熟蟲卵,常規法孵化毛蚴.將釘螺與毛蚴按不同比例進行感染,感染方式分為箇體感染和集體感染.箇體感染隨機分6組(Ⅰ～Ⅵ組),每組200隻釘螺,每隻釘螺置單孔內分彆感染,釘螺感染毛蚴比例分彆為1:0,1:5,1:10,1:15,1:20,1:25;集體感染隨機分6組(Ⅶ～Ⅻ組),每組200隻釘螺,按組彆集中感染,Ⅶ～Ⅻ組釘螺感染毛蚴比例分彆同Ⅰ～Ⅵ組.然後對每組釘螺的感染數、死亡數及尾蚴逸齣量進行比較,確定最佳感染方法和比例.以第1代人工感染性釘螺逸齣的尾蚴感染實驗動物,穫取成熟蟲卵併孵化毛蚴,然後採用箇體感染方式,以1:15的比例繼續感染釘螺,穫得第2代人工感染性釘螺.比較第1代與第2代人工感染性釘螺的感染數、死亡數及尾蚴逸齣數.通過動物感染實驗,比較人工第1代、第2代感染性釘螺與自然感染性釘螺日本血吸蟲成蟲髮育率、每剋糞卵數(fecal eggs per gram, FEPG)及每剋肝卵數(liver eggs per gram, LEPG). 結果:箇體感染Ⅰ～Ⅵ組的釘螺感染數分彆為0±0,22.7±4.2,31.7±4.5,53.0±5.3,39.3±5.9,32.7±4.7;釘螺死亡數分彆為21.7±3.1,25.0±3.6,31.3±4.9,44.7±6.5,78.3±9.5,89.7±13.6;釘螺平均逸蚴量為0±0,308.0±96.6,428.1±146.2,527.0±171.1,571.4±148.9,602.9±356.3.集體感染Ⅶ～Ⅻ組,釘螺感染數分彆為0±0,12.3±2.5,18.7±4.7,28.3±4.2,33.3±4.7,29.3±5.5;釘螺死亡數分彆為22.7±3.8,23.7±4.5,28.3±5.5,47.0±9.5,75.7±8.5,86.3±12.2;釘螺平均逸蚴量為0±0,244.5±57.3,292.3±74.8,347.1±100.8,477.2±142.1,447.3±161.4.用人工製備的第1代感染性釘螺對血吸蟲進行人工傳代研究,成功穫得瞭人工第2代感染性釘螺,感染率為24.65%,釘螺死亡率為24.50%;與人工第1代釘螺26.65%的感染率及22.35%的死亡率差異均無統計學意義(P>0.05).在尾蚴感染動物試驗中,人工第1代、第2代感染性釘螺與自然感染性釘螺的成蟲髮育率分彆為68.50%,73.50%,71.00%,3組間差異無統計學意義(P>0.05);自然感染性釘螺和人工第1代、第2代感染性釘螺的FEPG分彆為1 503±269,1 683±233,1 541±117;LEPG分彆為6 641±1 819,6 272±1 419,7 263±1 643,3組間比較差異無統計學意義(P>0.05). 結論:通過用人工感染的方法可以穫得日本血吸蟲感染性釘螺.箇體感染方式優于集體感染方式,感染時釘螺與毛蚴的最佳比例為1:15.人工感染性釘螺經傳代後,第1代與第2代釘螺在感染數、死亡數及尾蚴逸齣數等方麵無明顯差彆.比較人工第1代、第2代感染性釘螺與自然感染性釘螺的成蟲髮育率、FEPG及LEPG,差異也無統計學意義,證明人工傳代的血吸蟲尾蚴(室內株)能達到自然野生株尾蚴的感染效果.
목적:통과인공방법장호북정라제비성혈흡충감염성정라,학정정라감염적최가조건,건립정라인공감염전대적실내주,위연구기감염활성、유전변이화역묘등제공실험실의거.방법:용니룡견사집란법수집일본혈흡충성숙충란,상규법부화모유.장정라여모유안불동비례진행감염,감염방식분위개체감염화집체감염.개체감염수궤분6조(Ⅰ～Ⅵ조),매조200지정라,매지정라치단공내분별감염,정라감염모유비례분별위1:0,1:5,1:10,1:15,1:20,1:25;집체감염수궤분6조(Ⅶ～Ⅻ조),매조200지정라,안조별집중감염,Ⅶ～Ⅻ조정라감염모유비례분별동Ⅰ～Ⅵ조.연후대매조정라적감염수、사망수급미유일출량진행비교,학정최가감염방법화비례.이제1대인공감염성정라일출적미유감염실험동물,획취성숙충란병부화모유,연후채용개체감염방식,이1:15적비례계속감염정라,획득제2대인공감염성정라.비교제1대여제2대인공감염성정라적감염수、사망수급미유일출수.통과동물감염실험,비교인공제1대、제2대감염성정라여자연감염성정라일본혈흡충성충발육솔、매극분란수(fecal eggs per gram, FEPG)급매극간란수(liver eggs per gram, LEPG). 결과:개체감염Ⅰ～Ⅵ조적정라감염수분별위0±0,22.7±4.2,31.7±4.5,53.0±5.3,39.3±5.9,32.7±4.7;정라사망수분별위21.7±3.1,25.0±3.6,31.3±4.9,44.7±6.5,78.3±9.5,89.7±13.6;정라평균일유량위0±0,308.0±96.6,428.1±146.2,527.0±171.1,571.4±148.9,602.9±356.3.집체감염Ⅶ～Ⅻ조,정라감염수분별위0±0,12.3±2.5,18.7±4.7,28.3±4.2,33.3±4.7,29.3±5.5;정라사망수분별위22.7±3.8,23.7±4.5,28.3±5.5,47.0±9.5,75.7±8.5,86.3±12.2;정라평균일유량위0±0,244.5±57.3,292.3±74.8,347.1±100.8,477.2±142.1,447.3±161.4.용인공제비적제1대감염성정라대혈흡충진행인공전대연구,성공획득료인공제2대감염성정라,감염솔위24.65%,정라사망솔위24.50%;여인공제1대정라26.65%적감염솔급22.35%적사망솔차이균무통계학의의(P>0.05).재미유감염동물시험중,인공제1대、제2대감염성정라여자연감염성정라적성충발육솔분별위68.50%,73.50%,71.00%,3조간차이무통계학의의(P>0.05);자연감염성정라화인공제1대、제2대감염성정라적FEPG분별위1 503±269,1 683±233,1 541±117;LEPG분별위6 641±1 819,6 272±1 419,7 263±1 643,3조간비교차이무통계학의의(P>0.05). 결론:통과용인공감염적방법가이획득일본혈흡충감염성정라.개체감염방식우우집체감염방식,감염시정라여모유적최가비례위1:15.인공감염성정라경전대후,제1대여제2대정라재감염수、사망수급미유일출수등방면무명현차별.비교인공제1대、제2대감염성정라여자연감염성정라적성충발육솔、FEPG급LEPG,차이야무통계학의의,증명인공전대적혈흡충미유(실내주)능체도자연야생주미유적감염효과.
Objective To prepare the infected Oncomelania hupensis by artificial method for the research on the activity, vaccine, and genetic variation of Schistosoma Japonicum (S. Japonicum).Methods The mature eggs of S. Japonicum were collected by Nylon silk method and the miracidia were incubated under appropriate conditions. Negative snails were infected with miracidia in different proportion by means of individual or collective infection to seek the best method and proportion of infection between miracidia and snails. Infected snails were divided into 12 groups in total. Ⅰ-Ⅵ groups were for individual infection and Ⅶ-Ⅻ groups were for collective infection. There were 200 snails in each group. The infection ratios between snails and miracidia in Group Ⅰ-Ⅵ or screened, numbered, and reared singly. The amount of cercariae was calculated once every 10 days until the infected snails died. Then cercariae shedding quantity, infection quantity, and mortality of infected snails in every group were compared to find the best infection method and the best infection proportion between miracidia and snails. The cercariae were collected from the first generation of infected snails and were used to infect experimental animals. The mature eggs of S. Japonicum were saved from the infected experimental animals and incubated to get miracidia. The snails were artificially infected by miracidium to get the second generation of infected snails. The developmental rates of adult worms, the egg density in fecal and liver were compared between artificially and naturally infected snails. Results In individual infection GroupⅠ-Ⅵ,the average infection value of snails were 0±0,22.7±4.2,31.7±4.5,53.0±5.3,39.3±5.9,32.7±4.7,the average fatality of snails were 21.7±3.1,25.0±3.6,31.3±4.9,44.7±6.5,78.3±9.5,89.7±13.6, and the average value of cercariae shedding from infected snails were 0.0±0.0,308.0±96.6,428.1±146.2,527.0±171.1,571.4±148.9,602.9±356.3, respectively. In collective infection Group Ⅶ-Ⅻ,the average infection value of snails were 0±0,12.3±2.5,18.7±4.7,28.3±4.2,33.3±4.7,29.3±5.5,and the average fatality of snails were 22.7±3.8,23.7±4.5,28.3±5.5,47.0±9.5,75.7±8.5,86.3±12.2, and the average value of cercariae shedding from infected snails were 0±0,244.5±57.3,292.3±74.8,347.1±100.8,477.2±142.1,447.3±161.4, respectively. The second generation of artificially infected snails was obtained successfully. The average infection rate and fatality rate for the second generation of artificially infected snails were 24.65% and 24.50%, both of which were not obviously different from that of the first generation of artificially infected snails (P>0.05). In the animal experiment, the worm growth rate for the naturally infected snails, the first or second generation of artificially infected snails were 68.50%,73.50% or 71.00%. There was no obvious difference among them (P>0.05). The fecal (or liver) eggs per gram for the naturally infected snails, the first or the second generation of artificially infected snails were 1 503±269,1 683±233, or 1 541±117 (or 6 641±1 819,6 272±1 419, or 7 263±1 643). There was no significant difference among the 3 groups (P>0.05). Conclusion Infected snails can be obtained through the artificial method by using S. Japonicum miracidia to infect snails. Individual infection has the advantage over collective infection. The optimal proportion of infection between first and the second generation of artificially infected snails in the average of cercariae shedding, infection, and fatality average of snails. There was no significant difference between artificially and naturally infected snails in the developmental rate of adult worms, fecal and liver eggs per gram.
