A viral metagenomics approach was used to investigate fecal samples of Japanese calves with and without diarrhea. Of the different viral pathogens detected, read counts gave nearly complete astrovirus-related RNA sequences in 15 of the 146 fecal samples collected in three distinct areas (Hokkaido, Ishikawa, and Kagoshima Prefectures) between 2009 and 2015. Due to the lack of genetic information about bovine astroviruses (BoAstVs) in Japan, these sequences were analyzed in this study. Nine of the 15 Japanese BoAstVs were closely related to Chinese BoAstVs and clustered into a lineage (tentatively named lineage 1) in all phylogenetic trees. Three of 15 strains were phylogenetically separate from lineage 1, showing low sequence identities, and clustered instead with an American strain isolated from cattle with respiratory disease (tentatively named lineage 2). Interestingly, two of 15 strains clustered with lineage 1 in the open reading frame (ORF)1a and ORF1b regions, while they clustered with lineage 2 in the ORF2 region. Remarkably, one of 15 strains exhibited low amino acid sequence similarity to other BoAstVs and was clustered separately with porcine astrovirus type 5 in all trees, and ovine astrovirus in the ORF2 region, suggesting past interspecies transmission.

ABSTRACT. We examined nasal swab and lung homogenate samples collected from pigs experimentally and naturally infected with Mycoplasma hyopneumoniae for the detection of M. hyopneumoniae by the nested PCR (nPCR) and culture methods. In the 23 experimentally infected pigs, M. hyopneumoniae was commonly detected in nasal swabs by the nPCR and culture methods at 4 weeks after inoculation, and there was a significant correlation (P<0.01) between the titers of viable organisms in nasal swabs and in lung homogenates in the experimentally inoculated pigs. In the naturally infected pigs, on the other hand, discrepancies in detection were found between nasal swab and lung homogenate samples in 17 of 36 cases, although the presence of gross lung lesions correlated relatively well with the detection of organisms from the samples. Our results indicated that the diagnosis of mycoplasmal pneumonia by nPCR in individual pigs with nasal swabs is reliable under these experimental conditions. At present, nPCR with nasal swabs should only be used for monitoring the disease status at the herd level under field conditions.

We report here the first analysis of Erysipelothrix spp. using pulsed-field gel electrophoresis (PFGE). Seventy strains of Erysipelothrix spp. were analyzed. SmaI, AscI, and NotI were tested for the ability to cleave the DNA extracted from those strains, and among them, SmaI was the most reliable enzyme. Sixty-three distinct PFGE patterns were produced, and no DNA degradation was observed, allowing the identification of all of the strains. Based on these results and on those of a previous analysis using randomly amplified polymorphic DNA and ribotyping, PFGE with SmaI might be considered to be more sensitive than those methods and to be the best method for epidemiological studies of strains of this genus.Erysipelothrix rhusiopathiae is a gram-positive, slender, and straight or slightly curved rod that causes a wide spectrum of diseases in animals, birds, and humans (14,49). This bacterium has been isolated in most parts of the world, not only from sick and healthy animals but even from pork, seafood, retail game meat, and chicken meat (11,19,26,27,38,40,44). Human infections with this bacterium are usually related to occupational exposure (33). However, infection after consumption of undercooked pork and infections of patients with no history of contact with animals or skin lesions have been reported, and in many cases, the source of infection has not been identified (6,13,20,28,37). Moreover, potential errors in the recognition of this organism isolated from human infections due to unusual clinical presentations and the possibility of underdiagnosed infections have been reported (3, 10, 34). PCR-based assays for the rapid diagnosis of Erysipelothrix species have been described (22, 39, 42). However, to proceed with an epidemiological study and identify the source of infection, it is necessary to be able to identify each strain isolated from a case or outbreak, as well as the relatedness among the strains isolated from the possible source.During the last few years, molecular biological methods such as randomly amplified polymorphic DNA (RAPD), ribotyping, and pulsed-field gel electrophoresis (PFGE) have been demonstrated to be reliable tools for the differentiation of species and strains of one genus and for use in epidemiological studies of several pathogenic bacteria (9,15,16,24,32,(46)(47)(48). Although PFGE has been considered to be the "gold standard" among these methods (30), studies have shown that this method can be less sensitive than ribotyping and PCR-based methods with regard to the ability to differentiate between bacterial strains of some species (5,36,45). Moreover, there is no standard and universal PFGE protocol for all species of bacteria and it is necessary to adapt the procedures and choose a suitable enzyme for each genus or species. However, the use of this method for strains of the genus Erysipelothrix has not been reported. Therefore, we describe herein the first analysis of a large collection of Erysipelothrix species strains by PFGE. MATERIALS AND METHODSBacterial strains. Seventy strai...

ABSTRACT. To obtain blood biochemical basic data of Japanese Black calves in Kagoshima Prefecture, Japan, blood samples were obtained from 582 clinically healthy calves on 27 farms. Calves were divided into three stages: the suckling stage (between 14 and 90 days of age, n=191), the early growing stage (between 91 and 180 days of age, n=200) and the late growing stage (between 181 and 270 days of age, n=191). The mean concentration of total cholesterol, triglyceride, nonesterified fatty acids, calcium and zinc, and the mean activities of γ-glutamyltransferase and alkaine phospatase in the suckling stage were significantly higher than those in the early and late growing stages (P<0.01). The mean concentration of total protein, albumin and globulin increased gradually with growing. The mean concentration of beta-hydroxybutyrate in the suckling stage was below 150 µmol/l, however, it elevated above 400 µmol/l in the early and late growing stages. The mean concentration of copper concentration was above 70 µg/dl in all stages. The mean concentration of zinc was between 90 and 110 µg/dl in all stages. These results suggest that the blood biochemical values of Japanese Black calves vary with growing stages, and the blood parameters obtained in this study are considered useful as indices for health management of Japanese Black calves.