Hess M, Grabensteiner E, Liebhart D
Clinic for Avian, Reptile and Fish Medicine, Department for Farm Animals and Herd Management, University of Veterinary Medicine, Veterinärplatz 1, A-1210 Vienna, Austria.
Avian Pathol. 2006 Aug;35(4):280-5. doi: 10.1080/03079450600815507.
In the present investigation, the pathogenicity and transmission of a mono-eukaryotic culture of Histomonas meleagridis for commercial turkeys and specific pathogen free (SPF) chickens is described for the first time. Two separate trials with the same kind of experimental design were performed, one with commercial turkeys and one with SPF chickens. In each experiment, two different groups were included, which were housed in separate rooms. The first group contained four control birds, whereas the second group consisted of 10 infected and four in-contact birds. The birds were infected via the cloaca at 14 days of age with 380,000 cells of a mono-eukaryotic culture of H. meleagridis consisting of a cloned isolate (Turkey/Austria/2922-66/04). Reisolation of the parasite from turkeys and chickens under experimental conditions was performed for the first time. The infected birds started to excrete the parasite as soon as 2 days post infection. Rapid spread of the parasite to in-contact turkeys and chickens was noticed, based on reisolation of live parasites. Reisolation of the pathogen was impossible from two of the four in-contact SPF chickens at any time, whereas all of the infected turkeys were found positive. Intermittent shedding of the parasite was noticed in infected turkeys and SPF chickens, but the phenomenon was much more severe in the SPF chickens as these birds survived the infection. All of the infected and in-contact turkeys died between days 11 and 14 post infection, whereas no death was recorded in the SPF chickens, which were killed 6 weeks after the infection. Typical lesions were recorded in the caeca and livers of the infected turkeys. In addition, a heavy destruction of the bursa of Fabricius was seen in all of the infected and one of the in-contact turkeys. Altogether, the present investigations are of importance for an understanding of the pathogenicity and transmission of H. meleagridis in poultry.
在本研究中，首次描述了火鸡组织滴虫单真核培养物对商品火鸡和无特定病原体（SPF）鸡的致病性及传播情况。进行了两项采用相同实验设计的独立试验，一项针对商品火鸡，另一项针对SPF鸡。在每个实验中，包含两个不同的组，分别饲养在不同的房间。第一组有4只对照鸟，而第二组由10只感染鸟和4只接触感染鸟组成。这些鸟在14日龄时通过泄殖腔接种380,000个火鸡组织滴虫单真核培养物细胞，该培养物由一个克隆分离株（土耳其/奥地利/2922 - 66/04）组成。首次在实验条件下从火鸡和鸡中重新分离出该寄生虫。感染鸟在感染后2天就开始排出寄生虫。基于活寄生虫的重新分离，发现该寄生虫迅速传播到接触感染的火鸡和鸡。在任何时候，4只接触感染的SPF鸡中有2只无法重新分离出病原体，而所有感染的火鸡均呈阳性。在感染的火鸡和SPF鸡中均观察到寄生虫的间歇性排出，但在SPF鸡中这种现象更为严重，因为这些鸡在感染后存活下来。所有感染和接触感染的火鸡在感染后第11天至第14天之间死亡，而在感染6周后被处死的SPF鸡中未记录到死亡情况。在感染火鸡的盲肠和肝脏中记录到典型病变。此外，在所有感染的火鸡和1只接触感染的火鸡中均观察到法氏囊严重受损。总之，本研究对于理解火鸡组织滴虫在家禽中的致病性和传播具有重要意义。
