RESUMO
The bacterium Avibacterium paragallinarum is the etiologic agent of infectious coryza of chickens. Serovar C-1 has emerged in infectious coryza outbreaks in layer hens of Ecuador and Mexico. In the current study, genotyping and phylogenetic analyses of five Ecuadorian and 10 Mexican isolates of Av. paragallinarum serovar C-1 were performed. All 15 isolates share a unique enterobacterial repetitive intergenic consensus-based-PCR fingerprint and have identical 16S ribosomal RNA and hemagglutinin antigen gene sequences. Results indicate that Ecuadorian and Mexican isolates of serovar C-1 of Av. paragallinarum have a clonal relationship.
Assuntos
Galinhas , Genótipo , Infecções por Haemophilus/microbiologia , Haemophilus paragallinarum/genética , Doenças das Aves Domésticas/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Equador , Haemophilus paragallinarum/metabolismo , México , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA/veterináriaRESUMO
Between 2008 and 2010, 14 isolates of Avibacterium paragallinarum were identified as serovar C-1 in Mexico. All isolates were obtained from commercial laying hens suffering infectious coryza despite a history of vaccination. The enterobacterial repetitive intergenic consensus-based PCR genotyping showed that all isolates had a common pattern. Until recently, serovars A-1, A-2, B-1, and C-2 were the serovars prevalent in Mexico. Serovar C-1 has been identified in Japan and recently in the Americas in Ecuador. Our current study suggests that Av. paragallinarum serovar C-1 is an emerging serovar in Mexico. Our results also indicate that the Mexican isolates of Av. paragallinarum serovar C-1 may have a clonal relationship. Knowledge of the genetic diversity of Av. paragallinarum may be of value in understanding vaccine performance and identifying the best combination to achieve broader protection.
