An increasing incidence of enteric disorders clinically suggestive of the poult enteritis complex has been observed in turkeys in France since 2003. Using a newly designed real-time reverse transcriptase-polymerase chain reaction assay specific for the nucleocapsid (N) gene of infectious bronchitis virus (IBV) and turkey coronaviruses (TCoV), coronaviruses were identified in 37% of the intestinal samples collected from diseased turkey flocks. The full-length spike (S) gene of these viruses was amplified, cloned and sequenced from three samples. The French S sequences shared 98% identity at both the nucleotide and amino acid levels, whereas they were at most 65% and 60% identical with North American (NA) TCoVand at most 50% and 37% identical with IBV at the nucleotide and amino acid levels, respectively. Higher divergence with NA TCoV was observed in the S1-encoding domain. Phylogenetic analysis based on the S gene revealed that the newly detected viruses form a sublineage genetically related with, but significantly different from, NA TCoV. Additionally, the RNAdependent RNA polymerase gene and the N gene, located on the 5? and 3? sides of the S gene in the coronavirus genome, were partially sequenced. Phylogenetic analysis revealed that both the NA TCoV and French TCoV (Fr TCoV) lineages included some IBV relatives, which were however different in the two lineages. This suggested that different recombination events could have played a role in the evolution of the NA and Fr TCoV. The present results provide the first S sequence for a European TCoV. They reveal extensive genetic variation in TCoV and suggest different evolutionary pathways in North America and Europe.

The susceptibility of 135 Streptococcus suis strains isolated from pigs (n = 110) and from humans (n = 25) to 13 antimicrobial agents was studied by microdilution and disc diffusion methods using Mueller-Hinton Agar II (MH) supplemented with either defibrinated sheep blood (MHSB) or horse serum (MHHS). Results were similar for both methods used except for penicillin G whose zone diameters were reduced with MHSB compared with MHHS. When MH was supplemented with sheep blood, 39% of S. suis strains classified as penicillin susceptible by MHHS microdilution showed intermediate susceptibility. Nearly all strains were susceptible to penicillin G (except by disc diffusion in MHSB), amoxicillin, ceftiofur, florfenicol, gentamicin and bacitracin. The least active antimicrobial agents were doxycycline and macrolides/lincosamides. High-level resistance (MIC > 500 mg/L or zone diameters < 10 mm) to streptomycin and kanamycin was detected in only a few strains. The virulence of strains did not seem to be related to antimicrobial resistance because no statistical difference was reported between the proportion of resistant strains of S. suis isolated from pigs with meningitis, septicaemia and arthritis, and those from tonsils and nasal cavities. However, significant differences were found in the proportions of macrolide- or doxycycline-resistant strains between S. suis serotype 2 and other serotypes. The results of antibiotic susceptibility testing presented in this study indicate that beta-lactams can be used in empirical treatment of human and pig S. suis infections in France.

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-A total of 323 isolates of Streptococcus suis recovered from diseased or healthy pigs in France were serotyped. The presence of virulence-related proteins, Muraminidase-Released Protein (MRP), Extracellular Factor (EF) and Suilysin was also studied in 122 isolates of capsular types 2, 1/2, 9, 7 and 3 to evaluate their implication in virulence of S. suis. Capsular types 2, 1/2, 9, 7 and 3 were the most frequently detected (93%), with 69% for the capsular type 2 alone. Capsular types 2, 1/2, 9, 7, 3, 1, 4, 8, 18, 10 and 12 were isolated from diseased pigs, whereas types 2, 7, 9, 1/2, and 3 originated from the nasal cavities or tonsils of healthy animals. Most of the S. suis type 2 isolates recovered from diseased pigs carried MRP+ EF-Suilysin-(46%) or MRP+ EF+ Suilysin+ (28%) phenotypes. The MRP+ EF-Suilysin-phenotype was also detected in 67% of S. suis type 2 strains isolated from healthy pigs. The production of the virulence-related proteins was less frequently found in S. suis types 1/2, 9, 7 and 3 recovered either from diseased or healthy pigs. In this study, all the capsular type 1/2 strains were MRP+ EF-Suilysin-and all the S. suis type 7 harboured an MRP-EF-Suilysin-phenotype. The MRP-EF-Suilysin-phenotype was found in S. suis types 2, 3, 7 and 9 isolated from septicaemia, meningitis, pneumonia, and pleurisy. These results suggest that the presence of these proteins should not be used as a single condition for classifying the virulence of a field isolate in France. Streptococcus suis / capsular type / virulence / swine

Minimum inhibitory concentrations of doxycycline and oxytetracycline were determined against 55 Pasteurella multocida strains, 59 Actinobacillus pleuropneumoniae strains and 26 Mycoplasma hyopneumoniae strains isolated from the respiratory tract of pigs. An additional set of 76 P multocida strains isolated from pneumonic pigs was tested for their minimum inhibitory concentrations of doxycycline. The P multocida and A pleuropneumoniae strains were isolated in France and the minimum inhibitory concentrations were determined by an agar dilution method. The M hyopneumoniae strains were isolated in the United Kingdom and minimum inhibitory concentrations were determined by a serial broth dilution method. All the strains tested were susceptible to doxycycline whereas 15 per cent of the P multocida strains and 22 per cent of the A pleuropneumoniae strains were resistant to oxytetracycline. Doxycycline concentrations inhibiting 90 per cent of strains were 1 microgram/ml for P multocida and 2 micrograms/ml for A pleuropneumoniae. The ratio of the minimum inhibitory concentrations of doxycycline and oxytetracycline ranged between 1/1 and 1/4 for the oxytetracycline-susceptible strains and between 1/16 and 1/64 for the oxytetracycline-resistant strains. All the M hyopneumoniae strains were susceptible to doxycycline and oxytetracycline, the concentrations inhibiting 90 per cent of strains being 1 microgram/ml and 2 micrograms/ml, respectively. These data confirm that doxycycline has a higher in vitro activity against pig respiratory pathogens than oxytetracycline.