Coinfection ofAvibacterium paragallinarumandOrnithobacterium rhinotrachealein Chickens from Peru

Abstract

The coinfection of Avibacterium paragallinarum and Ornithobacterium rhinotracheale in two outbreaks of infectious coryza from Peru is reported. The diagnosis was confirmed by bacteriologic isolation, PCR testing, and sequencing of the 16S rRNA gene. The susceptibility of the isolates to 12 antimicrobial agents was tested by a disk diffusion method. The isolates were susceptible to amoxicillin/clavulanic acid and florfenicol and were resistant to oxacillin and sulfamethoxazole/trimethoprim. The coinfection of Av. paragallinarum and O. rhinotracheale and the severity of clinical signs were evaluated by experimental infection of specific-pathogen-free chickens. The group inoculated with O. rhinotracheale alone presented minimal clinical signs in 3 of 10 chickens. However, the groups inoculated with both Av. paragallinarum and O. rhinotracheale induced the most-severe clinical signs compared with the group inoculated with Av. paragallinarum alone. In conclusion, coinfections with Av. paragallinarum and O. rhinotracheale may occur, and these outbreaks could be more severe than single infections. Hence, the prevention, control, and diagnosis of Av. paragallinarum with O. rhinotracheale are important in outbreaks of infectious coryza.

First report on the molecular detection, phylogeny, virological and pathological investigations of Avibacterium paragallinarum in chickens in Turkey

“…The present study, carried out to investigate for the first time the pathology and molecular characteristics The findings of this study suggest that A. paragallinarum may be an emerging pathogen in Turkish poultry flocks showing respiratory signs and swollen heads, since mortality reached up to 16% within two weeks. Outbreaks of infectious coryza produced by A. paragallinarum have been reported to cause higher mortality under field conditions than in experimental trials (15)(16)(17). The clinical signs observed in affected chickens, such as ruffled feathers, respiratory distress, a swollen head, submandibular edema, sticky eyes, and purulent nasal discharge, were similar to those reported previously (10,21).…”

“…The serogroups A, B, and C represent three distinct immunovars. Most of the commercial vaccines include A. paragallinarum in combination with serovars A-1, B-1, C-1, or C-2 (16). The HA protein plays a key role in the virulence and pathogenicity of A. paragallinarum and is considered as a potential vaccine candidate.…”

“…A. paragallinarum is of paramount importance in the poultry industry because of its worldwide distribution and may contribute to the formation of "respiratory disease complex" under field conditions, thus leading to more severe clinical signs. It has been reported that A. paragallinarum provokes acute inflammation of the upper respiratory tract and facilitates the growth of other bacterial and viral pathogens (16,17).…”

A transient increase in MHC-IIlow monocytes after experimental infection with Avibacterium paragallinarum (serovar B-1) in SPF chickens

“…The well-characterized Av. paragallinarum isolate FARPER-107 (serovar B-1) was used in this study [ 23 ]. This bacterium was isolated in 2013 from an infectious coryza outbreak on a broiler farm in Arequipa, Peru, as described by Morales and collaborators [ 23 ].…”

“…As a model for infectious coryza, SPF chickens (16- or 37-week-old) were experimentally infected with Av. paragallinarum ( serovar B-1) via intrasinus instillation, following the same methodology previously reported [ 23 ]. Chickens in the control group were paired according to sex and age.…”