The complete genome of Mycoplasma gallisepticum strain R low has been sequenced. The genome is composed of 996 422 bp with an overall G+C content of 31 mol%. It contains 742 putative coding DNA sequences (CDSs), representing a 91 % coding density. Function has been assigned to 469 of the CDSs, while 150 encode conserved hypothetical proteins and 123 remain as unique hypothetical proteins. The genome contains two copies of the rRNA genes and 33 tRNA genes. The origin of replication has been localized based on sequence analysis in the region of the dnaA gene. The vlhA family (previously termed pMGA) contains 43 genes distributed among five loci containing 8, 2, 9, 12 and 12 genes. This family of genes constitutes 10?4 % (103 kb) of the total genome. Two CDSs were identified immediately downstream of gapA and crmA encoding proteins that share homology to cytadhesins GapA and CrmA. Based on motif analysis it is predicted that 80 genes encode lipoproteins and 149 proteins contain multiple transmembrane domains. The authors have identified 75 proteins putatively involved in transport of biomolecules, 12 transposases, and a number of potential virulence factors. The completion of this sequence has spawned multiple projects directed at defining the biological basis of M. gallisepticum. INTRODUCTIONPhylogenetic analyses indicate that mycoplasmas (class Mollicutes) have undergone a degenerative evolution from related, low G+C content, Gram-positive eubacteria (Rogers et al., 1985;Woese et al., 1980). The reduction of the mycoplasma genome has resulted in the loss of the cell wall and has limited the biosynthetic capabilities of these organisms. As a consequence of this loss of biosynthetic machinery, mycoplasmas are obligate parasites and rely on the uptake of many essential molecules from their environment.Mycoplasmas have long been considered model systems for defining the minimal set of genes required for a living cell (Morowitz, 1984). For this reason, it was not surprising when Mycoplasma genitalium (580 kb) was selected as one of the first targets for complete genome sequencing (Fraser et al., 1995). Since this initial report, the genomes of four additional mycoplasmas have been sequenced, Mycoplasma pneumoniae (816 kb; Dandekar et al., 2000;Himmelreich et al., 1996), Ureaplasma urealyticum (752 kb; Glass et al., 2000), Mycoplasma pulmonis (964 kb; Chambaud et al., 2001) and Mycoplasma penetrans (1358 kb; Sasaki et al., 2000). Theoretical and experimental approaches have estimated the minimum number of essential mycoplasma genes to be between 265 and 350 (Hutchison et al., 1999;Mushegian & Koonin, 1996).Abbreviations: CDS, coding DNA sequence; COGs, conserved orthologous groups.The GenBank accession number for the sequence reported in this paper is AE015450. Mycoplasma gallisepticum is an avian pathogen involved in chronic respiratory disease in chickens resulting in considerable economic losses in poultry production. Infection with this bacterium is spread by aerosol exposure and egg transmission. Outbreaks spread...

BackgroundAntimicrobial stewardship (AMS) programs are yet to be widely implemented in veterinary practice and medical programs are unlikely to be directly applicable to veterinary settings.ObjectiveTo gain an in‐depth understanding of the factors that influence effective AMS in veterinary practices in Australia.MethodsA concurrent explanatory mixed methods design was used. The quantitative phase of the study consisted of an online questionnaire to assess veterinarians’ attitudes to antimicrobial resistance (AMR) and antimicrobial use in animals, and the extent to which AMS currently is implemented (knowingly or unknowingly). The qualitative phase used semi‐structured interviews to gain an understanding of the barriers to and enablers of AMS in veterinary practices. Data were collected and entered into NVivo v.11, openly coded and analyzed according to mixed methods data analysis principles.ResultsCompanion animal, equine, and bovine veterinarians participated in the study. Veterinary practices rarely had antimicrobial prescribing policies. The key barriers were a lack of AMS governance structures, client expectations and competition between practices, cost of microbiological testing, and lack of access to education, training and AMS resources. The enablers were concern for the role of veterinary antimicrobial use in development of AMR in humans, a sense of pride in the service provided, and preparedness to change prescribing practices.Conclusion and Clinical ImportanceOur study can guide development and establishment of AMS programs in veterinary practices by defining the major issues that influence the prescribing behavior of veterinarians.

Problems can arise when vaccines and wild strains of a chicken herpesvirus recombine.

Pulsed-field gel electrophoresis and antimicrobial sensitivity testing were used as tools to investigate the epidemiology of Streptococcus uberis mastitis in dairy cows. A total of 62 different strains were found among 138 isolates from the four herds investigated, and between 10 and 26 different strains were found in each herd. There was no strain common to all four herds. Identical strains of S. uberis were detected from different quarters of individual cows and from cows within the same herd, suggesting that transmission from quarter to quarter and cow to cow had occurred. Despite the great variation in S. uberis strains, persistent infection with the same strain within a lactation was observed in most cows. Predominant strains were present in two herds. Preliminary investigations could not clarify why these particular strains might predominate, but in one herd there was a significant difference between the prevalence of clinical mastitis in quarters infected with the predominant strain and that in quarters infected with other strains, suggesting the greater virulence of the predominant strain. The wide variety of S. uberis strains found is consistent with an environmental source of S. uberis. However, evidence of direct transmission, the persistence of infection, and the predominance of particular strains in some herds indicate that S. uberis infections are epidemiologically complex and that the relative importance of these factors in the occurrence of mastitis may differ between herds.