Antimicrobial susceptibility, plasmid profiles and haemocin activities of Avibacterium paragallinarum strains

• Published in: Veterinary microbiology 2007-10, Vol.124 (3), p.209-218
• Main Authors: Hsu, Yuan-Man, Shieh, Happy K., Chen, Wei-Hao, Sun, Tsung-Yu, Shiang, Jia-Hsiang
• Format: Article
• Language: English
• Subjects: Animals; Anti-Bacterial Agents - pharmacology; antibiotic resistance; Antimicrobial susceptibility; avian infectious coryza; Avibacterium paragallinarum; bacterial infections; Bacteriocins - metabolism; Bacteriology; Base Sequence; biochemical mechanisms; Biological and medical sciences; bird diseases; Chickens; Colony Count, Microbial - veterinary; Disease Outbreaks - veterinary; DNA, Bacterial - chemistry; Dose-Response Relationship, Drug; Drug Resistance, Bacterial - genetics; Drug Resistance, Multiple, Bacterial - genetics; epidemiological studies; erythromycin; Fundamental and applied biological sciences. Psychology; Gene Amplification; genes; Haemocin; Haemophilus Infections - epidemiology; Haemophilus Infections - microbiology; Haemophilus Infections - veterinary; Haemophilus paragallinarum; Haemophilus paragallinarum - drug effects; Haemophilus paragallinarum - genetics; Haemophilus paragallinarum - pathogenicity; kanamycin; microbial genetics; Microbial Sensitivity Tests - veterinary; Microbiology; molecular genetics; multiple drug resistance; neomycin; pathogenicity; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; plasmids; Plasmids - genetics; Polymerase Chain Reaction; Poultry Diseases - epidemiology; Poultry Diseases - microbiology; pYMH5; serotypes; Serotyping - veterinary; streptomycin; sulfonamides; viral proteins; Virulence
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2007.04.024

In this study, 18 Avibacterium paragallinarum isolates collected in Taiwan from 1990 to 2003 were serotyped and tested for resistance to antimicrobial agents. Serotyping revealed that 13 isolates were Page serovar A and 5 isolates were Page serovar C. More than 75% of the isolates were resistant to neomycin, streptomycin and erythromycin. The most common resistance pattern (15 isolates, 83.3%) was neomycin–streptomycin. Furthermore, 88.9% of the isolates were resistant to two or more antibiotics. About 72% of isolates contained plasmids (pYMH5 and/or pA14). Plasmid pYMH5 encoded functional streptomycin, sulfonamide, kanamycin and neomycin resistance genes and revealed significant homology to a broad host-range plasmid, pLS88. Plasmid pA14 encoded a putative MglA protein and RNase II, both of which might be associated with virulence. Furthermore, seven isolates showed haemocin activity. Plasmid pYMH5 is the first multidrug-resistance plasmid reported in A. paragallinarum and it may facilitate the spread of antibiotic-resistance genes between bacteria. The putative virulence plasmid pA14 and haemocin-like activity in A. paragallinarum indicate two possible mechanisms which might be responsible for the pathogenesis.