McCraw B M, Slocombe J O
Can J Comp Med. 1985 Oct;49(4):372-83.
The development and pathological effects of Strongylus equinus were studied in 17 pony foals and one horse foal raised in isolation and examined at necropsy from seven days to 40 wk postinfection (PI). Following inoculation of 15000 +/- 6% or 16000 +/- 6% infective larvae by stomach tube foals were monitored for clinical signs and selected blood changes. Larvae penetrated the wall of the ileum, cecum and colon. The molt to the fourth stage occurred mostly in the wall of the ventral colon before 2 wk PI and larvae attained the liver mainly via the peritoneal cavity as early as eight days PI and persisted in the liver until 17 wk PI. Following active migration within the liver, invasion of the pancreas was accomplished at least by 7 wk PI with maximum numbers at 17 wk. The fourth molt occurred about 15 wk PI and preadults were present in the wall of the ventral colon at 30 wk PI and in the lumen of the colon at 40 wk. Strongylus equinus tends to wander retroperitoneally to the flanks, perirenal fat, diaphragm, omentum and occasionally to the lungs. Between 1 and 4 wk PI small raised hemorrhagic areas were present on the serosa of the ileum and colon. Small white foci on the surface of the liver at 1 wk PI were followed by tortuous tracks 3 wk later. Pathological changes in the pancreas were evident at three months PI and more severe by four months. Granulomas containing larvae were common in the flanks, diaphragm, omentum and occasionally beneath the pleura of the lungs. Clinical signs were correlated with invasion of the pancreas, the fourth molt, maximum globulin values and high eosinophil counts.
对17匹小马驹和1匹单独饲养的马驹进行了研究，观察马圆线虫的发育及病理效应，这些马驹在感染后7天至40周进行尸检。通过胃管接种15000±6%或16000±6%感染性幼虫后，监测马驹的临床症状和选定的血液变化。幼虫穿透回肠、盲肠和结肠壁。至第四阶段的蜕皮大多发生在感染后2周前的腹侧结肠壁，幼虫最早在感染后8天主要通过腹腔进入肝脏，并在肝脏中持续存在至感染后17周。在肝脏内活跃移行后，至少在感染后7周侵入胰腺，感染后17周数量最多。第四次蜕皮发生在感染后约15周，感染后30周成虫前期存在于腹侧结肠壁，感染后40周存在于结肠腔内。马圆线虫倾向于腹膜后游走至胁腹、肾周脂肪、膈肌、网膜，偶尔也会游走至肺部。感染后1至4周，回肠和结肠浆膜上出现小的隆起出血区。感染后1周肝脏表面出现小白点，3周后出现曲折的痕迹。感染后3个月胰腺出现明显病理变化，4个月时更严重。含有幼虫的肉芽肿常见于胁腹、膈肌、网膜，偶尔也见于肺胸膜下。临床症状与胰腺感染、第四次蜕皮、球蛋白最大值和嗜酸性粒细胞计数高有关。
