Guy J S, Levy M G, Ley D H, Barnes H J, Gerig T M
Department of Microbiology, Pathology, and Parasitology, North Carolina State University, Raleigh 27606.
Avian Dis. 1987 Oct-Dec;31(4):713-22.
Five-day-old bobwhite quails were inoculated with reovirus and Cryptosporidium previously isolated from the intestinal contents of young, commercially raised bobwhite quails experiencing severe enteritis. Quails inoculated with reovirus alone did not develop clinically apparent disease, infection was localized principally in the intestinal tract, and no lesions were detected. Quails inoculated with Cryptosporidium, alone or with reovirus, developed severe enteritis with high mortality and marked growth depression. Cryptosporidia caused blunting of intestinal villi and provoked a mononuclear cell response in the lamina propria. The severity of intestinal lesions correlated with numbers of parasites. An apparent synergistic effect in dually infected quails was indicated by enhanced Cryptosporidium oocyst shedding, greater numbers of cryptosporidia in the intestinal tracts, and systemic reovirus infection. In addition, multifocal liver necrosis was detected in dually infected quails but was absent in quails infected with only reovirus or Cryptosporidium. The results suggest that Cryptosporidium promoted systemic spread of reovirus, and reovirus intensified Cryptosporidium infection, but no significant synergistic effect on mortality or weight gain was detected. The most important agent in the naturally occurring acute enteritis of bobwhite quails was Cryptosporidium.
给5日龄的北美鹑接种先前从患有严重肠炎的商业化养殖幼龄北美鹑肠道内容物中分离出的呼肠孤病毒和隐孢子虫。单独接种呼肠孤病毒的鹌鹑未出现明显的临床疾病，感染主要局限于肠道，未检测到病变。单独接种隐孢子虫或同时接种呼肠孤病毒和隐孢子虫的鹌鹑出现严重肠炎，死亡率高且生长明显受抑。隐孢子虫导致肠绒毛变钝，并在固有层引发单核细胞反应。肠道病变的严重程度与寄生虫数量相关。双重感染鹌鹑中隐孢子虫卵囊排出增加、肠道中隐孢子虫数量增多以及全身性呼肠孤病毒感染表明双重感染鹌鹑存在明显的协同效应。此外，在双重感染的鹌鹑中检测到多灶性肝坏死，但仅感染呼肠孤病毒或隐孢子虫的鹌鹑中未出现。结果表明，隐孢子虫促进了呼肠孤病毒的全身扩散，呼肠孤病毒加剧了隐孢子虫感染，但未检测到对死亡率或体重增加有显著的协同效应。北美鹑自然发生的急性肠炎中最重要的病原体是隐孢子虫。
