巨型艾美耳球虫裂殖子的分离和纯化

Isolation and purification of merozoites of Eimeria maxima

[目的]为了获得纯净的巨型艾美耳球虫(Eimeria maxima)裂殖子。[方法]对25日龄白羽肉鸡口服接种3×105巨型艾美耳球虫卵囊,在其感染后48~124 h取十二指肠末端到卵黄蒂后5 cm处肠段,收集裂殖子并计数,确定分离裂殖子的最佳时间;将所取肠段均分为5段,分别对裂殖子进行计数,筛选分离裂殖子的最佳肠段;通过DEAE-52纤维素柱层析对裂殖子进行纯化并分管收集,确定收集较高纯度裂殖子的最佳时间。[结果]在感染后84 h所收集的裂殖子最多;此外,从空肠中后段及空肠末端肠段中分离出较多数量的裂殖子,占总数的62%以上;通过DEAE-52纤维素柱层析获得44 mL纯度较高的裂殖子。[结论]分离巨型艾美耳球虫裂殖子的最佳时间为感染后84 h,最佳肠段为空肠后段,收集1~44 mL洗脱液能够获得纯度较高的裂殖子。

[Objective] The study aims to isolate merozoites of Eimeria maxima from specific location of small intestine at appropriate time and obtain the merozoites with high purity. [Method] 25-day-old white feather broilers were inoculated with 3×105 sporulated oocysts of Eimeria maxima. Merozoites were harvested from midintestines(the end of duodenum to 5 cm behind the Meckel’s diverticulum) during 48-124 h postinfection and the number of merozoites were counted. In addition, the intestines were equally divided into 5 segments and numbered, and the merozoites in different segments were counted respectively. The harvested merozoites were further purified by DEAE-cellulose 52 anion exchange chromatography. [Result] The number of merozoites harvested at 84 h postinfection was the largest;In addition, the majority number of merozoites were isolated from the middle and distal segments of jejunum, which accounts for 62% of the total. 44 mL merozoites in purity were collected through DEAE-52 chromatography. [Conclusion] The appropriate time to isolate merozoites of Eimeria maxima is 84 h postinfection. The location to separate the merozoites is the distal jejunum. The merozoites with high purity can be obtained by collecting 1-44 mL liquid.