Infectious Coryza
Limited by the knowledge of microbes, infectious coryza was not regarded as a distinct avian disease until 1920s. In 1932, the causative agent was isolated and named as Haemophilus gallinarum afterwards. Based on the identification of Page in 1960s, H. paragallinarum was isolated and regarded as the true causative bacteria. However, recent researches have confirmed both these two species belong to Avibacterium genus and are both reason for the fowl coryza, while most researches suggested Av. paragallinarum plays the major role in recent outbreaks (Blackall & Soriano, 2008).
The major clinical signs for the disease are nasal discharge, facial swelling, sneezing, as well as diarrhea, anorexia and lacrimation (Blackall, 1999; …show more content…
The outbreak of infectious coryza has been reported worldwide since 1930s, farms in the North America, South America, Caribbean, Africa and Asia all had outbreak cases in the past 20 years (Byarugaba et al., 2007; Rajukar et al., 2009; Calderón et al., 2010; Chansiripornchai, 2010; Morales-Erasto et al., 2014; Mohammed et al., 2015). In recent years, no outbreak of infectious coryza has ever been reported in Australia, Korea and some other countries, however, bacterial isolates do have been identified in these …show more content…
First, good hygiene practice is critical in chicken farms. Due to the high separability of the diseases, keeping the flocks in a generally healthy state is the first action to consider (Gondwe & Wollny, 2007). Second, the possible carriers of the pathogen should be isolated from the healthy flocks. Breeding with a bird from an unknown source should be prohibited as they might be recovered carrier birds. Third, vaccines has been used in many countries for intervention. Inactivated bacterin vaccination on 10-20 weeks old chicken via subcutaneous or intramuscular routes was found to be effective, while oral route may be used with significant higher cell counts (Blackall & Soriano, 2008). However, the cross-protection effect under both serovars schemes are complicated and not fully understood, and it remains the bottleneck of the vaccine development (Blackall,
Limited by the knowledge of microbes, infectious coryza was not regarded as a distinct avian disease until 1920s. In 1932, the causative agent was isolated and named as Haemophilus gallinarum afterwards. Based on the identification of Page in 1960s, H. paragallinarum was isolated and regarded as the true causative bacteria. However, recent researches have confirmed both these two species belong to Avibacterium genus and are both reason for the fowl coryza, while most researches suggested Av. paragallinarum plays the major role in recent outbreaks (Blackall & Soriano, 2008).
The major clinical signs for the disease are nasal discharge, facial swelling, sneezing, as well as diarrhea, anorexia and lacrimation (Blackall, 1999; …show more content…
The outbreak of infectious coryza has been reported worldwide since 1930s, farms in the North America, South America, Caribbean, Africa and Asia all had outbreak cases in the past 20 years (Byarugaba et al., 2007; Rajukar et al., 2009; Calderón et al., 2010; Chansiripornchai, 2010; Morales-Erasto et al., 2014; Mohammed et al., 2015). In recent years, no outbreak of infectious coryza has ever been reported in Australia, Korea and some other countries, however, bacterial isolates do have been identified in these …show more content…
First, good hygiene practice is critical in chicken farms. Due to the high separability of the diseases, keeping the flocks in a generally healthy state is the first action to consider (Gondwe & Wollny, 2007). Second, the possible carriers of the pathogen should be isolated from the healthy flocks. Breeding with a bird from an unknown source should be prohibited as they might be recovered carrier birds. Third, vaccines has been used in many countries for intervention. Inactivated bacterin vaccination on 10-20 weeks old chicken via subcutaneous or intramuscular routes was found to be effective, while oral route may be used with significant higher cell counts (Blackall & Soriano, 2008). However, the cross-protection effect under both serovars schemes are complicated and not fully understood, and it remains the bottleneck of the vaccine development (Blackall,