家兔精液传播弓形虫的实验研究(英文)

Study on the Transmission of Toxoplasma gondii by Semen in Rabbits

目的了解弓形虫能否通过精液传播,并探讨雌兔阴道不同健康状态对精液传播弓形虫的影响。方法8只健康新西兰雄兔经腹腔分别感染1×105个RH株弓形虫速殖子,分别于感染前、后用假阴道采集雄兔精液,每周将采集到的精液混合液化后0.1ml/只,分别经宫腔内人工受精管感染4组阴道健康状态不同的成年新西兰雌兔(阴道正常组、阴道损伤组、滴虫性阴道炎组和霉菌性阴道炎组),共采集8周,将所得8份混合精液分别感染8次。每次受精后第2～3天耳缘静脉采血2ml,分别用ELISA和PCR检测血清抗弓形虫抗体和全血中弓形虫B1基因片段。结果ELISA结果显示,雌兔在初次受精后第16天可检测到抗弓形虫抗体,第1～4组抗体阳性家兔数分别有2、1、3和1只,ELISA阳性率为25.9%(7/27)。PCR检测最早在受精后3d和最晚51d可扩增出弓形虫B1基因片段200bp,第1～4组阳性家兔数分别有2、1、2和0只,PCR阳性率为18.5%(5/27)。其中两种检测结果均为阳性的3只。结论弓形虫可通过精液感染雌兔。雌兔的阴道健康状态对经精液感染弓形虫无影响。

Objective To confirm the transmission of Toxoplasma gondii by semen and to investigate the impact of vaginal status on the transmission of T.gondii in female rabbits. Methods Sixteen male rabbits were infected with T.gondii by intraperitoneal injection each with l xl（P RH tachyzoites. Eight rabbits died in 8-14 d after infection. Artificial vagina was used to collect semen from male rabbits weekly before and after infection for 8 weeks. If more than 2 portions of semen from 8 survived male rabbits were collected after infection, the collected semen was mixed weekly for later use. Twenty-seven female rabbits were divided into 4 groups： group I with normal vagina （7 rabbits）, group 2 with wounded vagina （7）, group 3 with trichomonas vaginitis （7） and group 4 with colpomycosis infection （6）. Tachyzoites were found in mixed semen digested by trypsinase, and were used for endovaginal artificial insemination to female rabbits by uterine cavity tube once a week for 8 consecutive weeks. 2-3 d after every insemination, 2 ml blood was collected from helix vein of each rabbit, and stored at -40℃ for use. Anti-T. gondii antibody was examined by ELISA and the BI gene of T.gondii was detected by PCR. Results Anti-T. gondii antibody was detected in some rabbits （2, 3, 1, and 1 rabbits from each of the groups respectively） on the 16th day after the first insemination. The positive rate of ELISA was 25.9%. The amplification of BI gene （200 bp） by PCR appeared positive from the blood samples on the 3rd day after the first insemination and the last positive one was proved on the 51^th day after the first insemination. Number of positive samples was 2, 1, 3 and 1 in the 4 groups respectively, with an overall PCR positive rate of 18.5%. Only 3 of the 27 rabbits were positive by both ELISA and PCR. Conclusions T.gondii can be transmitted by semen and the health status of vagina shows no impact on it.