Pulmonary Aspergillosis in Apparently Healthy Young Rabbits

Abstract

Abstract. Pulmonary aspergillosis was discovered in apparently healthy young rabbits. Thirty-five rabbits of various ages raised in the same rabbitry were examined by histological, ultrastructural and microbiological methods. The pulmonary lesions were found only in rabbits younger than five weeks old. These lesions contained characteristicallv shaDed hvDhae surrounded by eosinophilic radiating projections-"asteroid structure of the "asteroid bodies" is discussed.Aspergillosis has been reported in almost all species of domestic animals, birds, and in many wild speCies. I,4,8, 10.12 Pulmonary aspergillosis also has been reported in many species of domesticIn rabbits, pulmonary aspergillosis is only of historical significance, particularly since standards have advanced in recent times.6 It is well documented in the older European literature,6. 14, but only one report describing aspergillosis in rabbits was found in more recent 1iterat~re.I~ This is a report of pulmonary aspergillosis in apparently healthy young rabbits.as well as in wild 9-1 l , 13, I6 Materials and MethodsAn apparently healthy 19-day-old female rabbit was purchased for blood sampling from a commercial rabbitry and was necropsied after sampling. Numerous granulomatous white nodular lesions were observed in the lung, therefore 34 nine-to 109-day-old rabbits, which were raised in the same rabbitry described above, were examined. Rabbits in this rabbitry were kept in raised wire cages and fed a commercial rabbit diet and water ad libitum. Nest boxes were constructed of plywood. Rice straw, packed in 18 liter cans and sterilized at 180°C for 30 minutes before use, was used as nesting material. The animal houses were air-conditioned and kept at a temperature of 24 f 1°C with a humidity of 65%. All animals in this rabbitry were apparently healthy. Some animals in this rabbitry had been examined periodically for microbiological contamination by culturing the lung. Pusteurellu multocidu was not isolated at any time.All rabbits examined were anesthetized by chloroform and -~ _ _bodies." The significance of the disease condition and the killed by blood sampling from the hearts. Following necropsy, the lung, heart, liver, spleen, and kidney were fixed in 4% phosphate-buffered paraformaldehyde. All tissue samples were processed by conventional methods, embedded in paraffin, sectioned at 4 pm, and stained with hematoxylin and eosin (HE). Selected sections were stained with periodic acidSchiff reaction (PAS), Giemsa stain, Gridley's stain, Grocott's stain, Ziehl-Neelsen's carbol-fuchsin, azan and Gomori's reticulin methods. Pulmonary lesions of two 21-day-old male rabbits were examined by electron microscopy. Immediately after death, lesions of the lung were fixed in 4% paraformaldehyde in 0.5 M phosphate buffer, then fixed in 1.5% osmium tetroxide, and embedded in glycol methacrylate. Ultrathin sections were stained with uranyl nitrate followed by lead citrate.Eleven 21-to 109-day-old rabbits were examined for microbiology. After the lungs were removed asepti...

Zygomycotic Lymphadenitis in Slaughtered Feedlot Cattle

“…16 Although electron microscopic and immunohistochemical studies revealed that asteroid bodies were composed of cytoplasm of surrounding neutrophils and deposits of immunoglobulins, there is still confusion in the literature regarding the origin and composition of these bodies. 17,28,31 In our study, 190 (98%) of the cases involved mesenteric lymph nodes, whereas only 4 (2.1%) involved mediastinal nodes. Similar anatomic distribution was reported in a Danish study: 84 cases (89.4 %) were mesenteric, 7 cases (7.4 %) were mediastinal, and 3 cases (3.2 %), were both mesenteric and mediastinal.…”

“…The structure of these bodies is compatible with so-called asteroid bodies, a name widely used in the literature to describe radiating eosinophilic material often associated with fungal elements in cases of zygomycosis. 3,11,12,17,19,20,28,31 However, the expression has been used to describe morphologically distinct structures, and some authors have used this expression interchangeably with the term Splendore-Hoeppli. 16 Although electron microscopic and immunohistochemical studies revealed that asteroid bodies were composed of cytoplasm of surrounding neutrophils and deposits of immunoglobulins, there is still confusion in the literature regarding the origin and composition of these bodies.…”

Biology and Diseases of Rabbits

“…Pulmonary aspergillosis has been described in otherwise healthy young rabbits at a rabbitry in Japan (Matsui et al, 1985). Aspergillosis associated specifically with Aspergillus flavus or A. fumigatus has been reported sporadically .…”

The Genus Aspergillus

“…This develops no further in healthy individuals, as it is held in check by the secretions of the surrounding host response to its presence. It remains viable, encased in a thick envelope of antibody-rich material and is visible in histological preparationsas an"asteroid body" (Austwick, 1962;Matsui et al, 1985).…”