Jarvinen Julie Ann C, Whitley Elizabeth M, Kreuder Amanda J, Schleining Jennifer A
1Julie Ann C. Jarvinen, Department of Veterinary Pathology, 1786 College of Veterinary Medicine, Iowa State University, 1600 South 16th Street, Ames, IA 50011.
J Vet Diagn Invest. 2014 Jan;26(1):178-83. doi: 10.1177/1040638713516626. Epub 2014 Jan 7.
Infection with Lamanema chavezi, a parasitic nematode of New World camelids, was diagnosed by examination of feces and formalin-fixed liver from a 14-month-old female llama (Lama glama) that died after a 6-week illness. Infection with L. chavezi was initially suspected when a granuloma containing an unidentified nematode was detected microscopically in the hepatic parenchyma from a necropsy specimen. The subsequent diagnosis of L. chavezi infection was based on the morphologic features of 2 immature nematodes dissected from individual hepatic granulomas, characteristics of eggs detected in feces of the llama by centrifugal flotation in sugar solution (specific gravity: 1.30), development of third-stage larvae within the eggs after incubation of the llama feces at room temperature for ≥30 days, and the morphology of third-stage larvae released from the embryonated eggs. Collectively, these findings indicate that the llama, born and raised in Oregon, harbored an autochthonous L. chavezi infection. Eggs identified as L. chavezi were also detected by centrifugal flotation of pelleted feces from 3 of 7 herd mates of the llama indicating this parasite is endemic in the Oregon herd. The findings reported herein serve to alert diagnosticians and veterinary practitioners to the occurrence of L. chavezi in New World camelids in the United States and describe diagnostic features of this potential pathogen.
从一只患病6周后死亡的14月龄雌性美洲驼(小羊驼)的粪便和福尔马林固定肝脏中检查发现,其感染了新世界骆驼科动物的寄生线虫查韦斯拉马线虫(Lamanema chavezi)。尸检标本的肝实质中发现一个含有不明线虫的肉芽肿,最初怀疑感染了查韦斯拉马线虫。随后对查韦斯拉马线虫感染的诊断基于从单个肝肉芽肿中解剖出的2条未成熟线虫的形态特征、通过糖溶液离心浮选法(比重:1.30)在美洲驼粪便中检测到的虫卵特征、将美洲驼粪便在室温下孵育≥30天后虫卵内第三期幼虫的发育情况以及从带胚胎的虫卵中释放出的第三期幼虫的形态。总体而言,这些发现表明这只在俄勒冈州出生和长大的美洲驼感染了本地的查韦斯拉马线虫。通过离心浮选法从这只美洲驼的7个同群伙伴中的3个的粪便沉淀中也检测到了被鉴定为查韦斯拉马线虫的虫卵,表明这种寄生虫在俄勒冈州的驼群中呈地方性流行。本文报告的这些发现旨在提醒诊断人员和兽医从业者注意美国新世界骆驼科动物中查韦斯拉马线虫的出现情况,并描述这种潜在病原体的诊断特征。