贝氏隐孢子虫对丝毛乌骨鸡的致病性试验

EXPERIMENTAL CRYPTOSPORIDIOSIS IN THE SILKIEFOWL BLACK BONE WITH CRYPTOSPORIDIUM BAILEYI

２ 日龄丝毛乌骨鸡经口接种贝氏隐孢子虫（ Ｃｒｙｐｔｏｓｐｏｒｉｄｉｕｍ ｂａｉｌｅｙｉ）卵囊２×１０６ 个／只，潜隐期４ｄ，排卵囊开放期１８ｄ，排卵囊高峰期为感染后（ Ｐ Ｉ Ｄ）７～１４ｄ。呼吸道症状出现于 Ｐ Ｉ Ｄ１０，死亡率为１３３％ （２／１５）。扫描电镜观察发现气管纤毛脱落，寄生有各阶段发育虫体及杆形细菌和渗出的红细胞；法氏囊也寄生有大量虫体，粘膜上皮细胞肥大，微绒毛脱落， Ｐ Ｉ Ｄ２０ 在法氏囊粘膜表面见有许多虫体逸出后留下的带虫空泡。试验证明丝毛乌骨鸡为贝氏隐孢子虫的新宿主。使用扫描电镜系统观察了贝氏隐孢子虫感染引起的组织形态学病理变化。

Fifteen 2 day old silkiefowl Black Bone were orally inoculated with 2×10 6 oocysts per bird,the prepatent period was 4 days.Oocysts discharge lasted 18 days,and a peak level of oocyst output occurred on 7th to 14th day post inoculation(PID),the birds orally inoculated,displayed signs of respiratory cryptosporidiosis from 10PID and death rate was 13.3% (2/15).It was observed by scaning electron microscopy (SEM) that trachea cilia was in a state of chaos or deciliation,with endogenous developmental stages of C.baileyi attached to mucosal surface and bacillus,red blood cell on it.There were many parasites attached to mucosal surface of bursal of Fabricius (BF),with mucosal epithelial cells hypertrophied and microvilli lost.There were many residual of parasitophorous vacuole attached to the mucosal surface of BF on 20PID.It is proved that Silkiefowl Black Bone is a new host of C.baileyi and the histophathologic changes of mucosal surface with inoculation of C.baileyi by SEM were described.