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We describe two cases of mucormycosis with systemic and gastrohepatic involvement in two male poodles. Respiratory, neurological and gastrointestinal signs progressed to death within 3 and 19 days of the onset of clinical signs, respectively. In case 1, there was systemic disease affecting the lungs, heart and brain. The lesions were characterized by yellow or red, raised, irregular areas that extended into deeper tissue from the surface. In case 2, there was gastric rupture; the margins of the rupture and the gastric mucosa were covered by a thick, white, friable material. In the liver, there were multiple yellow-white cavitated nodules. Histologically, pyogranulomas occurred in the affected organs and were associated with vasculitis, thrombosis and fungal hyphae. The diagnosis of mucormycosis was based on the characteristic microscopical lesions together with the morphology and staining features of the fungus. The hyphae were strongly labelled by monoclonal antibody specific for Rhizopus arrhizus on immunohistochemistry. Underlying immunosuppression was suspected in both cases., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In spring 2014, several wild passeriform garden birds were found severely ill or dead, all with severe periocular swellings. A blue tit (Cyanistes caeruleus) showing severe depression was humanely destroyed and sent for necropsy examination. In this bird, the lower eyelids were sagging, red and oedematous. Microscopical examination revealed marked infiltration of the eyelid tissue with fungal hyphae (stained by periodic acid-Schiff) without any inflammatory reaction. Polymerase chain reaction followed by sequencing identified Mucor racemosus and a so far unknown circovirus. The circovirus infection in this bird might have induced immunosuppression and thus facilitated the fungal infection. To our knowledge this is the first report of ocular M. racemosus infection associated with circovirus infection in a bird., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

An adult female killer whale (Orcinus orca) was transported to the Port of Nagoya public aquarium in June 2010. While the animal was being maintained in the aquarium there was a gradual decrease in body weight. On October 1st, 2010 the whale exhibited signs of gastrointestinal disease and died on January 14th, 2011. At necropsy examination the gastric compartments were filled with a large number of variably-sized rocks (total weight 81.4 kg) and there was marked ulceration in the third compartment. There were multifocal tubercle-like nodules within the lungs and on sectioning there were numerous abscesses and pulmonary cavities. Microscopically, there was severe suppurative pneumonia associated with fungal hyphae that were infrequently septate and often branched. Numerous bacterial colonies were also present. The hyphae demonstrated immunohistochemical cross-reactivity with Rhizomucor spp. and Cunninghamella bertholletiae was cultured. Bacteriological culture revealed the presence of Proteus mirabilis, Pseudomonas aeruginosa and Pseudomonas oryzihabitans. This case represents the first documentation of zygomycosis associated with C. bertholletiae in a marine mammal., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

An adult male finless porpoise (Neophocaena phocaenoides) kept in an aquarium in Japan displayed loss of appetite and reduced body weight over several months. Necropsy examination revealed the presence of lesions in the pericardium, lung, and mediastinal and pancreatico-duodenal lymph nodes. Microscopically, these comprised regions of necrotizing granulomatous inflammation with multinucleated giant cells and surrounding fibrosis. Fungal hyphae were identified within macrophages and the extracellular tissue. Immunohistochemical labelling determined that these organisms were of the order Mucorales. A diagnosis of granulomatous pericarditis associated with systemic mucormycosis was made.

Nine male and five female adult free-living platypuses, obtained in a prospective capture-release study from northern Tasmania, exhibited gross features of cutaneous mycosis caused by Mucor amphibiorum. The lesions were present on the hind limbs (six cases), front limbs (four), tail (five), dorsal trunk (three) and ventral trunk (one). They varied in size, and ranged from raised red nodules or plaques, which sometimes exuded purulent material, to ulcerated lesions with central cavitation, red exuding centres and raised epidermal margins. Older lesions were covered either partly or fully by thickened and irregular epidermis. Histological examination of skin biopsies revealed discrete, poorly encapsulated granulomas, or more commonly a diffuse granulomatous or pyogranulomatous inflammation. Inflammatory cells consisted of neutrophils or eosinophils, sparse plasma cells and lymphocytes, many macrophages and occasional multinucleated giant cells. Fibrovascular tissue was diffusely and irregularly scattered in the granulomatous regions. Sphaerules characteristic of M. amphibiorum infection were observed in all lesions. The cutaneous distribution of the lesions and the natural history of the platypus indicated that entry of M. amphibiorum may have been via superficial skin wounds. T cells were the predominant infiltrating lymphoid cells in the diffuse lesions, indicating the importance of the cell-mediated response to infection., (Copyright 2000 Harcourt Publishers Ltd.)

Decreased feed intake and persistent low-level mortality in a production tank of hybrid tilapia (Oreochromis niloticus x Oreochromis mossambicus x Oreochromis aureus) prompted the submission of three affected fish for diagnosis. Consistent macrosopical findings included multifocal dermal haemorrhage, excess abdominal fluid and an enlarged friable liver. On microscopical examination, broad non-septate fungal hyphae and chlamydospores were identified within numerous internal organs, often within and adjacent to blood vessels. The fungal hyphae were readily seen by silver staining (GMS) and the chlamydospores were stained deep magenta by the periodic acid-Schiff reaction. In addition to several species of Gram-negative bacteria, moderate growths of woolly white fungal colonies were obtained from the posterior part of the kidney in two of the three tilapia. These colonies were identified as a Rhizomucor sp. on the basis of the morphological characteristics of the sporulating fungi in culture. This represents the first reported episode of zygomycosis in fish., (Copyright 1999 Harcourt Publishers Ltd.)

Invasive pulmonary mycosis caused by Aspergillus niger and Rhizopus stolonifer is reported in a 2-year-old horse, one of three that died after being housed in a disused, uncleaned stable. Lesions were characterized by thrombosis of the blood vessels with haemorrhage and tissue necrosis. Fungal hyphae were observed both in thrombosed vessels and in adjacent necrotic tissue. In culture media inoculated with lung samples and samples from the bedding hay, two types of colony were recorded and identified as A. niger and R. stolonifer. This study is the first description of equine pulmonary mucormycosis and of A. niger as an aetiological agent in the horse.

Of 73 goats on a dairy farm, 27 developed mycotic mastitis in the post-partum period. Purulent mammary secretion, progressive induration of the affected glands, slight fever and weight loss were observed. As treatment produced no improvement within 2-3 weeks, all diseased animals were slaughtered. At post-mortem examination, widespread acute and chronic mycotic lesions were seen throughout the affected glands. Infection was thought to have spread through the milk ducts as an ascending infection resulting from prophylactic intramammary treatment with antibiotic before parturition. In all lesions, aspergillus hyphae were identified by indirect immunofluorescent labelling, which gave a strong and uniform reaction with polyclonal and monoclonal antibodies to Aspergillus fumigatus. In a single granulomatous lesion, zygomycotic hyphae were also identified immunohistochemically. At terminal swellings of aspergillus hyphae, "yeast-like bodies" were produced, a phenomenon which seems to be associated with special, but unknown, circumstances.

The reactivity of a panel of rabbit hyperimmune antisera raised against somatic antigens of three zygomycetes, Absidia corymbifera, Rhizopus oryzae and Rhizomucor (Mucor) pusillus was assessed by crossed immunoelectrophoresis (XIE) and indirect immunofluorescence (IIF) staining of experimentally infected murine tissues. Despite a widespread cross-reactivity of the neat antisera, heterologous absorption rendered antisera monospecific as assessed by XIE. Heterologous absorption also rendered the antisera against R. oryzae and R. (Mucor) pusillus specific by IIF, whereas heterologous absorption of Abs. corymbifera antiserum did not abolish reactivity with R. oryzae. The reactivity of the heterologously absorbed antisera and a murine monoclonal IgG1 antibody against Abs. corymbifera enabled zygomycetes within bovine lesions to be identified. Of 113 zygomycotic lesions of 95 cattle examined, 82 (72.5 per cent) showed a pattern of reactivity compatible with Abs. corymbifera, 21 (18.6 per cent) with R. oryzae, and 5 (4.4 per cent) with R. (Mucor) pusillus. Fungi in four lesions reacted with the monoclonal antibody only, and fungal elements in one lesion showed no reactivity at all. Each of the bovine lesions contained only a single fungal species, but one animal was infected by Abs. corymbifera in the rumen and by R. oryzae in the other stomach compartments. Apart from being the main cause of systemic bovine zygomycosis in Denmark, Abs. corymbifera also seems to be the most pathogenic due to its frequent haematogenous and lymphatic spread (87.8 per cent) as compared with R. oryzae (1.4 per cent) and R. (Mucor) pusillus (5.4 per cent).

A 10-year study showed that 45 of 692 cattle aged > 6 months had systemic mycosis and, of these, 38 had alimentary mycosis. The percentages of these 38 cattle with lesions in various sites were: rumen (73.7), omasum (71.1), abomasum (34.2), reticulum (21.1), intestine (15.8), omasoabomasal orifice (7.9) and tongue (2.6). Infections in both the forestomachs and abomasum occurred in 31.6 per cent; mucormycosis was found in 94.7 per cent and aspergillosis in 31.6 per cent; 26.3 per cent (10 cattle) had complicated infections with both Mucorales and Aspergillus and eight of these animals had mixed lesions of both mucormycosis and aspergillosis. Macroscopically, focal haemorrhagic necrosis was seen in all 38 cattle. Histologically, thrombosis, coagulative necrosis and hyphae typical of the order Mucorales or of Aspergillus spp. were found. Many of the cattle were also affected by ruminal acidosis-inducing factors (ruminal atony 81.6 per cent, mastitis 63.2 per cent, "downer cow syndrome" 57.9 per cent and parturition 50.0 per cent), which may have predisposed to alimentary mycosis.