[Detection of Emericella nidulans from bedding materials in horse breeding environment and its significance as a causative agent of guttural pouch mycosis in horses].

Sixty-six new and used samples of horse bedding materials: 60 rice straws, 2 wheat straws, 2 timothy hays and 2 wood chips, were collected from horse breeding stables of 33 farms in Japan and examined for the presence of Emericella nidulans (E. nidulans; anam. Aspergillus nidulans). The incidence of E. nidulans in the bedding materials was 75.8% and there was no significant difference in detection of the fungus between the new and used materials (25 out of the 33 samples, respectively). The growth of E. nidulans isolated in sterilized rice straw culture was accelerated by the addition of water up to about Aw 0.94, which as determined to be the most favorable moisture content. The addition of 0.3% urea solution onto the sterilized rice straw culture also appeared to very effectively enhance its conidial and ascocarp formation. A significant influence of urea on conidial and ascocarp formation of E. nidulans isolates was confirmed by their cultures on a synthetic medium which had urea as the sole nitrogen. These results suggest that severe contamination of E. nidulans on new bedding materials can be hazardous and its proliferation can readily occur at the stable due to the enhancing effect of urine. This analysis is meaningful to elucidate a reservoir of E. nidulans as the causative agent of guttural pouch mycosis in horses.

[Biological characteristics of Emericella nidulans isolated from horse guttural pouch mycosis].

Seven strains of Emericella nidulans were isolated from lesions in the guttural pouch of horses with mycosis of this pouch. All strains grew in a wide range of temperature, pH and in five kinds of culture media. The optimum temperature that supported their growth was 38 degrees C, and all seemed to prefer an acidic environment with a pH of 4.0. Proliferative conidial formation was found to be induced by the aforementioned temperature and pH. Moreover, detection of beta-haemolysis and protease production suggested that these strains are biologically and biochemically active, which may imply that they have a potent pathogenicity of their own. Characteristics of two other strains of E. nidulans isolated from fomites were the same as those isolated from the infected horses. These findings suggest that E. nidulans is a potentially pathogenic to horses.

Bacterial contamination of ready-to-eat foods and fresh products in retail shops and food factories.

Raw vegetables cut for salad, cooked salad, cooked rice, boiled noodles, bean curd, and cooked Japanese foods were purchased in 27 retail shops in Tokyo. Intact vegetables before being processed and ready-to-eat fresh salad products were obtained from two food factories located in the suburbs of Tokyo. Two hundred thirty-eight retail samples, 137 samples of intact vegetables, and 159 samples of fresh products were examined for aerobic plate count (APC), coliforms, Escherichia coli, Listeria spp., Staphylococcus aureus, and Bacillus cereus. The APC of retail foods were 2.1 to 5.7 log CFU/g, and the range for the coliforms was 0.1 to 2.3 log CFU/g. The APC and coliform values showed that the raw vegetables cut for salad were the most heavily contaminated among the six kinds of ready-to-eat foods examined. Although L. monocytogenes was not detected, two samples of raw vegetables and five kinds of cooked foods yielded Listeria spp. S. aureus was detected in one sample of Japanese cooked food. The APC of the intact vegetables were 2.9 to 7.3 log CFU/g upon arrival and 2.2 to 7.2 log CFU/g after 3 days storage at 10 degrees C. The APC of the fresh products were 3.4 to 7.6 log CFU/g upon arrival and 4.7 to 8.7 log CFU/g after 3 days storage at 10 degrees C. The isolation rates for coliforms were 6.1 to 50% for intact vegetables and 50 to 66.7% for fresh products. E. coli was detected only in the fresh products. B. cereus was isolated from 20.1% (17 of 81) of the intact vegetables and 9.2% (8 of 87) of the fresh products.

Onychomycosis in white line disease in horses: pathology, mycology and clinical features.

This paper describes onychomycosis in horses and reports the pathological findings, associated fungi and incidence of concurrent white line disease. In addition to these observations, relevance between post mortem and clinical findings of onychomycosis are discussed in 3 necropsied horses. Samples were collected from 100 hooves from a total of 51 Thoroughbreds suffering from white line disease. Of these, 15 hooves from 13 horses were also complicated with severe hoof wall fissure formation. Preparations from the same samples were used both for histopathology and for culture to identify the associated fungi. Onychomycosis was diagnosed when it could be confirmed histologically. Fungal identification was based on morphological characteristics in culture and the associated fungi were determined by comparison with culture morphology. As a result, 10 samples collected from horses were diagnosed as suffering from onychomycosis. Seven of these showed complicating severe inner hoof wall fissures and the soil fungus Scedosporium apiospermum or the teleomorph of this fungus, i.e., Pseudallescheria boydii, was isolated. The fungus was found to be ubiquitous in the fissure cavities, the terminal horn of the white line and the terminal horn-like laminae of the metaplastic white line-like tissue. It can be concluded that onychomycosis frequently causes white line disease and/or makes it worse. Associated with deterioration of the submural condition, the main associated fungus for onychomycosis in this series, was Genus Scedosporium and the most susceptible region was the terminal horn of the hypertrophied white line and/or the terminal horn-like laminae of the metaplastic white line-like tissue.

Potential sources of sporadic human infection with Yersinia enterocolitica serovar O:8 in Aomori Prefecture, Japan.

In November 1992 and June and August 1993 rectal contents from 204 small mammals living in the wild were collected and examined for the presence of Yersinia enterocolitica serovar O:8 to clarify the source of human infections caused by this microbe in the Tsugaru Region of Aomori Prefecture, Japan. Serovar O:8 was isolated from 10 (5.2%) of 193 wild rodents trapped in June 1993 (9 of 107) and August 1993 (1 of 23) but not from animals trapped in November 1992 (0 of 63). This serovar was not isolated from 11 moles. From May to September 1993, 12 human patients were found to have become ill and to be infected with Y. enterocolitica O:8. The patients lived in the same districts where the wild rodents harboring serovar O:8 were trapped. Two different patterns by restriction enzyme analysis of the virulence plasmid were observed. One pattern obtained by restriction enzyme analysis of the virulence plasmid was observed in 20 isolates from 11 human patients and 9 wild rodents, and the other was observed in 2 isolates from 1 human patient and 1 wild rodent. These findings indicate that wild rodents seem to play an important role as a source of human Y. enterocolitica O:8 infection.