Jorgensen W K, Stewart N P, Jeston P J, Molloy J B, Blight G W, Dalgliesh R J
Department of Primary Industries, Animal Research Institute, Moorooka, Queensland.
Aust Vet J. 1997 Aug;75(8):592-5. doi: 10.1111/j.1751-0813.1997.tb14201.x.
To determine the presence of E praecox and E mitis in Australia, to isolate representative strains of these species from chickens and determine their pathogenicity.
Morphological, physiological and cross protection studies were undertaken to confirm the identity of Australian isolates of E praecox and E mitis.
Oocysts were isolated from a backyard flock at Jimboomba, southeastern Queensland and numbers of E praecox and E mitis enriched by passage in chickens immune to five other species of poultry Eimeria. Oocysts of mean conformation and size of the two species were purified by single oocyst passage. Two isolates that closely matched recorded parameters for E praecox and E mitis were selected and designated JP and JM respectively. The cross protection between the isolates and E acervulina was determined by infection and challenge experiments. The virulence of the two isolates was determined by comparing weight gains of groups of birds inoculated with JP isolate or JM isolate with untreated groups.
Isolates JP and JM most closely matched recorded parameters of E praecox and E mitis respectively. Groups of chickens, previously infected with JP and JM isolates, showed no significant protection against infection with E acervulina. In a separate trial, groups of susceptible chickens inoculated with 10(5) oocysts of JP and JM isolates showed significantly reduced weight gains compared with untreated controls.
Isolates JP and JM are E praecox and E mitis respectively, confirming the presence of these species in Australia. These isolates were found capable of causing significant reductions in weight gains in susceptible chickens.
确定澳大利亚是否存在早熟艾美耳球虫和缓艾美耳球虫，从鸡中分离出这些种类的代表性菌株并确定其致病性。
进行形态学、生理学和交叉保护研究，以确认澳大利亚分离出的早熟艾美耳球虫和缓艾美耳球虫的身份。
从昆士兰州东南部吉姆博omba的一个后院鸡群中分离出卵囊，通过在对其他五种家禽艾美耳球虫免疫的鸡中传代来富集早熟艾美耳球虫和缓艾美耳球虫的数量。通过单卵囊传代纯化这两种平均形态和大小的卵囊。选择了两个与记录的早熟艾美耳球虫和缓艾美耳球虫参数密切匹配的分离株，分别命名为JP和JM。通过感染和攻毒实验确定分离株与堆型艾美耳球虫之间的交叉保护作用。通过比较接种JP分离株或JM分离株的鸡群与未处理鸡群的体重增加情况来确定这两种分离株的毒力。
分离株JP和JM分别与记录的早熟艾美耳球虫和缓艾美耳球虫参数最接近。先前感染过JP和JM分离株的鸡群，对堆型艾美耳球虫感染没有显著的保护作用。在另一项试验中，接种10⁵个JP和JM分离株卵囊的易感鸡群与未处理的对照组相比，体重增加显著减少。
分离株JP和JM分别是早熟艾美耳球虫和缓艾美耳球虫，证实了这些种类在澳大利亚的存在。这些分离株能够使易感鸡的体重增加显著降低。
