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R A Earlé I G Horak F W Huchzermeyer G F Bennett L E Braack B L Penzhorn 《The Onderstepoort journal of veterinary research》1991,58(3):145-147
Bloodsmears were taken from separate groups of five helmeted guineafowls, Numida meleagris, shot at approximately monthly intervals at Skukuza and near Lower Sabie in the Kruger National Park during the period August 1988 to August 1990. Ninety-eight (86%) of 114 guineafowls had single or multiple infections of Aegyptianella sp., Haemoproteus pratasi, Hepatozoon sp., Leucocytozoon neavei, Plasmodium circumflexum and Trypanosoma numidae. The apparent seasonal prevalence of Aegyptianella sp., H. pratasi and L. neavei, the three most commonly occurring parasites (42%, 49% and 56% of birds infected respectively), is probably dependent on the presence of their respective vectors. 相似文献
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During the summer of 1990 deaths, occurred in racing camels (Camelus dromedarius) associated with a specific disease syndrome. Clinical signs included pyrexia, coughing, lachrymation, oedema of the throat and submandibular region and enlargement of submandibular lymph nodes. In terminal cases nervous signs were present and sometimes there was bloody diarrhoea and vomiting. Of 480 camels at least 70 animals were affected with the disease and about 40 died. Morbidity and mortality was greater in camels recently imported. Consistent necropsy findings were extensive petechial and ecchymotic haemorrhage beneath the epicardium, endocardium and visceral pleura and in the mediastinal lymph nodes, and haemorrhagic oedema of the pharyngeal and laryngeal areas. Haemorrhages occurred more variably in abdominal organs and on the omasal and abomasal mucosa. Bronchopneumonia, omasitis and abomasitis were observed on microscopic examination, together with liver and kidney lesions of presumed toxic origin. Fungal hyphae and, occasionally, the characteristic conidial morphology of Aspergillus fumigatus were seen in sections and direct smears from lesions in the respiratory and alimentary tracts. A fumigatus was cultured from trachea, bronchi, bronchioles, lung tissue, heart blood, omasum, abomasum, ileum and submandibular lymph nodes. Whether the role of Aspergillus in the overall syndrome is primary or secondary has not been established; no other potential aetiological agent has been identified. 相似文献