Antimicrobial Use in the Animal Sector in Japan from 2011 to 2022.

Evaluating antimicrobial use (AMU) is essential in the investigation and implementation of antimicrobial resistance (AMR) prevention measures. Here, we examined AMU using an index (mg/kg biomass) that considers the antimicrobial sales volume and livestock biomass in Japan from 2011 to 2022. Antimicrobial sales volumes were obtained from JVARM data, and biomass data were obtained from reliable statistics.

Molecular characteristics of CTX-M β-lactamase-producing and quinolone-resistant Escherichia coli among deer in a popular tourist spot in Japan.

Antimicrobial resistance (AMR) is a growing global concern. Clonal lineages of CTX-M β-lactamase-producing (CTXE) and quinolone-resistant (QREC) were disseminated among the deer population in a famous tourist destination (Nara Park; NP) in Japan. The molecular characteristics of CTXE or QREC isolates, which could pose a threat to public health, have not been elucidated.

Traces of pandemic fluoroquinolone-resistant clone ST131 transmitted from human society to aquatic environments and wildlife in Japan.

Transmission of antimicrobial-resistant bacteria among humans, animals, and the environment is a growing concern worldwide. The distribution of an international high-risk fluoroquinolone-resistant clone, ST131, has been documented in clinical settings. However, the transmission of ST131 from humans to surrounding environments remains poorly elucidated.

The first isolation of Clostridium massiliodielmoense from a dead beef cow in Japan and pitfalls to be aware of in identifying the Clostridium species.

Clostridium sp. was detected in the organs of a cow with black watery diarrhea in Japan. Results identifying this species were inconsistent; Clostridium novyi type A infection was suggested by PCR assay targeting Clostridium fliC region (fliC-multiplex PCR), while 16S rRNA gene sequencing identified the isolated bacteria as Clostridium massiliodielmoense.

Molecular characterization of an avian rotavirus a strain detected from a large-billed crow (Corvus macrorhynchos) in Japan.

Avian rotaviruses A (RVAs) are occasionally transmitted to animals other than the original hosts across species barriers. Information on RVAs carried by various bird species is important for identifying the origin of such interspecies transmission. In this study, to facilitate an understanding of the ecology of RVAs from wild birds, we characterized all of the genes of an RVA strain, JC-105, that was detected in a fecal sample of a large-billed crow (Corvus macrorhynchos) in Japan.

Quantitative tyramine analysis method for Apis mellifera larvae infected with Melissococcus plutonius, the causative agent of European foulbrood.

Tyramine, a trace monoamine produced from tyrosine by decarboxylation and found naturally in foods, plants, and animals, is a suspected virulence factor of Melissococcus plutonius that causes European foulbrood in honey bee brood. In the present study, we developed a method for quantitative analysis of tyramine in culture medium and honey bee larvae with a limit of quantitation of 3 ng/mL and a recovery rate of >97% using Liquid Chromatography-Mass Spectrometry/Mass Spectrometry and deuterium-labeled tyramine, demonstrating for the first time that a highly virulent M. plutonius strain actually produces tyramine in infected larvae.

Production of a selective antibacterial fatty acid against by strains.

C16 monounsaturated fatty acid (C16:1) show antibacterial activity against , a pathogen associated with various diseases such as atopic dermatitis and bacteremia, while the compound does not exhibit antibacterial activity against , an epidermal commensal that inhibits the growth of . In this study, we aimed to find bifidobacterial strains with the ability to produce C16:1 and to find a practical manner to utilize C16:1-producing strains in industry. Various strains were screened for their content of C16:1.

Improvement of the mismatch amplification mutation assay-PCR for discrimination between Streptococcus suis serotypes 2 and 1/2.

A mismatch amplification mutation assay (MAMA)-PCR, which detects a single-nucleotide polymorphism contributed to serological difference between Streptococcus suis serotypes 2 and 1/2, is used to discriminate between these serotypes. The present study reports unusual serotype 1/2 isolates untypable by the MAMA-PCR and improvement of the MAMA-PCR for typing such isolates.

Antimicrobial usage surveys using electronic medical records in cattle practice in Gifu Prefecture.

As the majority of antimicrobial treatments for cattle in Japan are prescribed by veterinarians, medical record information can be useful in clarifying the amount and purpose of antimicrobial use. In this study, we examined their amount and purpose in cattle practices in Gifu Prefecture. In cattle, approximately 85% of the antimicrobials are used for the treatment of gastrointestinal (50.

surface-antigen recognition by antibodies and bacterial elimination is influenced by capsular polysaccharide structure.

is an encapsulated bacterium causing severe diseases in swine. Here, we compared the protective properties of the capsular polysaccharide (CPS) of different serotypes by using serotype-switched mutants in a mouse model of infection. CPS structure influenced bacterial survival in mice, antibody binding, and antibody-mediated bacterial killing.

Atypical Melissococcus plutonius strains: their characteristics, virulence, epidemiology, and mysteries.

Melissococcus plutonius is a Gram-positive lanceolate coccus that is the causative agent of European foulbrood, an important bacterial disease of honey bee brood. Although this bacterium was originally described in the early 20th century, a culture method for this bacterium was not established until more than 40 years after its discovery due to its fastidious characteristics, including the requirement for high potassium and anaerobic/microaerophilic conditions. These characteristics were considered to be common to the majority of M.

Characterization of quinolone-resistant and extended-spectrum β-lactamase-producing Escherichia coli derived from sika deer populations of the Nara Prefecture, Japan.

Wildlife in urban areas have the potential to disseminate antimicrobial-resistant bacteria (ARB) across a wider environment. Using antimicrobial-supplemented agar plates, we isolated extended-spectrum β-lactamase-producing Escherichia coli (EEC) and quinolone-resistant E. coli (QREC) from 144, 23, and 30 deer feces from Nara Park (NP), rural area neighboring NP (RA), and Mt.

Generation and characterization of a genetically modified live rabies vaccine strain with attenuating mutations in multiple viral proteins and evaluation of its potency in dogs.

Live rabies vaccines have advantageous features that can facilitate mass vaccination for dogs, the most important reservoirs/transmitters of rabies. However, some live vaccine strains have problems in their safety, namely, risks from the residual pathogenicity and the pathogenic reversion of live vaccine strains. The reverse genetics system of rabies virus provides a feasible option to improve the safety of a live vaccine strain by, for example, artificially introducing attenuating mutations into multiple viral proteins.

Development of a Streptococcus pluranimalium-specific PCR assay.

Streptococcus pluranimalium, an emerging zoonotic pathogen associated with infections in various animal species and humans, cannot be reliably identified by phenotypic characterization using the commercial kits routinely used in laboratories. We herein developed the first S. pluranimalium-specific PCR assay useful for the easy and reliable identification of this species.

A calf with hind limb paralysis and dysstasia and a genome sequence analysis of an isolated Clostridium perfringens toxinotype E strain.

Clostridium perfringens toxinotype E infections are rare in calves, and the development of intestinal lesions were commonly observed. In 2012, a 6-day-old calf in Japan exhibited swelling with emphysema on the right gluteal region, sudden paralysis of the hind limb and dysstasia. A pathological examination revealed myositis of the gluteal muscle and neuritis of the ischiatic nerve.

Molecular Mechanisms of Aggregation of Canine SOD1 E40K Amyloidogenic Mutant Protein.

Canine degenerative myelopathy (DM) is a human amyotrophic lateral sclerosis (ALS)-like neurodegenerative disease. It is a unique, naturally occurring animal model of human ALS. Canine DM is associated with the aggregation of canine superoxide dismutase 1 (cSOD1), which is similar to human ALS.

MORPHOLOGIC OBSERVATION AND FIRST MOLECULAR CHARACTERIZATION OF ENCYCLOMETRA JAPONICA (DIGENEA: ENCYCLOMETRIDAE) IN THE DIGESTIVE TRACT OF WILD TIGER KEELBACKS (RHABDOPHIS TIGRINUS) IN JAPAN.

Encyclometra japonica Yoshida and Ozaki, 1929 is a fluke that parasitizes the digestive tract of snakes. When the species was first reported, it was originally characterized on the basis of morphologic features, namely, the characteristics of the 2 testes located obliquely in the anterior-posterior direction, and the position of the ventral sucker one-fourth to one-third from the anterior extremity. Thereafter, more specimens with other morphologic variations were reported, and a new morphologic feature for species discrimination was proposed.

Antimicrobial resistance and associated genetic background of isolated from clinically affected and healthy cattle.

, a member of the family, causes various diseases, including thrombotic meningoencephalitis and respiratory diseases. Here, 166 isolates recovered from Japanese cattle with various diseases between the late 1970s and the 2010s were subjected to susceptibility testing against 14 antimicrobials (ampicillin, amoxicillin, cefazolin, ceftiofur, kanamycin, streptomycin, nalidixic acid, enrofloxacin, danofloxacin, florfenicol, erythromycin, tylosin, oxytetracycline, and fosfomycin). The proportions of antimicrobial-resistant/intermediate isolates were low in the total isolates, with resistance rates ranging from 0% for ceftiofur and florfenicol to 13.

Disinfectant resistance of Salmonella in in vitro contaminated poultry house models and investigation of efficient disinfection methods using these models.

Salmonellaenterica subsp. enterica (Salmonella) shows disinfectant resistance by forming biofilms on solid surfaces. However, efficient disinfection methods to eliminate Salmonella biofilms from farms have not yet been examined in detail.

Whole-Genome Sequences of and sp. Strains Isolated from Honey in Japan.

Knowledge about bacterial species in bee environments is essential for maintaining healthy honeybee colonies. Therefore, we performed whole-genome sequence analysis on bacteria isolated from honey harvested in Japan. This study reports the genomic sequences of the five bacterial strains identified.

Establishment of a reverse genetics system for rabies virus strain Komatsugawa.

The rabies virus strain Komatsugawa isolated from a dog in Tokyo in the 1940s retains biological properties as a field strain, providing an effective model for studying rabies pathogenesis. To facilitate molecular studies on the pathogenesis, this study aimed to establish a reverse genetics system for the Komatsugawa strain. By transfecting the full-length genome plasmid of this strain, infectious virus with artificially introduced genetic markers in its genome was rescued.

Detection of macrolide resistance genes, ermC and ermB, in Japanese honey using real-time PCR assays.

American foulbrood (AFB) is a honeybee disease caused by Paenibacillus larvae, and tylosin is used as the prophylactic in Japan. Honey contains macrolide-resistant bacteria that are a potential source of genes that may confer tylosin resistance to P. larvae.