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Objective: To describe four cases of infection in cattle, from geographically different places, with a presumptive new species of Propionibacterium, which causes granulomatous lesions in the head, thorax, abdomen, pelvic area and skin., Procedure: Gross lesions, ranging from 0.5 to 15 cm and detected during routine carcase inspection at the abattoir, were submitted to the laboratory for routine testing in the National Granuloma Submission Program. The bacterium isolated was identified using morphological characteristics, biochemical reactions, cell wall components, products of fermentation and 16S rRNA gene sequencing., Results: Gross lesions submitted for examination consisted of a fibrous outer capsule enclosing thick yellow pus-like material. A Gram-Glynn stain of the histological sections revealed colonies of Gram-positive, filamentous, branching bacteria. Bacteriological culture, cell wall analysis, biochemical reactions and 16S rRNA sequencing identified the organism as a Propionibacterium sp closely related to P cyclohexanicum and the P freudenreichii cluster., Conclusion: This is the first report of a Propionibacterium sp closely related to P cyclohexanicum and the P freudenreichii cluster associated with extensive granulomatous lesions in cattle in Queensland. Sequencing data are suggestive of a previously undescribed species of the Propionibacterium genus.

Microbiological testing of crocodiles during the dressing procedure has shown that sanitising the skin before skinning reduces the bacterial count on the skin and that dipping crocodile meat in 1.3% acetic acid solution effectively reduces bacterial levels. The total bacterial count on the processed mean sample was comparable with that obtained in the beef, pork and lamb industries. Salmonellae were isolated from 14 of the 72 carcases. Most (65%) of these isolates were in Salmonella subspecies III, formerly classified as Arizona.

A single dose of 5 x 10(8) bacilli of Pseudomonas pseudomallei by intratracheal injection resulted in acute (21 cases) or chronic (19 cases) melioidosis in 40 of 48 pigs. Fifteen (10 acute and 5 chronic) had been immunosuppressed by cyclophosphamide before inoculation. The major clinical signs were initial fever, marked neutrophilia and, in the acute cases, respiratory distress. There were no signs of the nasal and ocular discharge, paresis or diarrhoea seen in acute cases in south-east Asia. The cyclophosphamide treatment caused a significant decrease in the neutrophil count by 7 d after inoculation in all 15 immunosuppressed pigs, and all were culture positive at necropsy. Eight of the 33 non-treated pigs were culture negative at necropsy. Pigs overcoming the initial phase of infection had more abscess-like nodules that were bacteriologically sterile at necropsy than the pigs with acute cases of melioidosis. P. pseudomallei was isolated predominantly from the spleen, lungs and the injection site. Although only one strain was used in this study, it is likely that Australian strains of P. pseudomallei are not as virulent as the south-east Asian isolates.

The effects in goats of the subcutaneous injection of varying doses of Pseudomonas pseudomallei (90 to 500,000 bacilli) suspended in normal saline are described. High doses (greater than or equal to 500 bacilli) caused acute, fatal infections. Lower doses (90 to 225 bacilli) caused acute or chronic disease when infection became established. However, 11 of 18 goats injected with the lower doses of bacilli showed no sign of infection on clinical or bacteriological examination. Response to antibiotic therapy with long acting tetracycline and chloramphenicol was minimal. Goats surviving the initial phase of infection tended to overcome the disease with a corresponding increase in the number of abscesses that were sterile at necropsy. In infected goats, clinical signs included undulating fever, wasting, anorexia, paresis of the hind legs, severe mastitis and abortion. At necropsy, abscesses were found predominantly in the spleen, lungs, subcutaneous injection site and its draining lymph node.