Assessment of immunization regimens of duck Riemerella anatipestifer vaccines

Abstract

Aims: Riemerella anatipestifer infections of goslings and ducklings can result in high mortality. Since there are at least 21 serotypes of R. anatipestifer, crossprotection is an important goal for vaccine development. Methods and Results: In this study, we evaluated the immunostimulatory effect of different immunization regimensthe traditional inactivated vaccine vs prime-boost regimens using DNA and protein subunit vaccines (DNA+subunit, subunit+subunit, subunit+inactivated and DNA+DNA). Results showed that, when compared to the inactivated vaccine, prime-boost regimens induced higher and up to 16-week longer lasting levels of antibody responses, significantly elevated the percentage of the cytotoxic CD8 + T cell and higher expression levels of IFN-c, IL-6 and IL-12 mRNAs. Furthermore, as an indication of cross-protection, sera from prime-boost regimens were able to recognize lysates of R. anatipestifer serotypes 1, 2 and 6. Conclusions: Prime-boost regimens especially DNA-prime and protein-boost, induce strong long-term immune response and may prove protective for breeder ducks requiring long-term protection. Significance and Impact of the Study: It is worth mentioning that the subunit+inactivated regimen group also elicited strong immune response. The cost of this regimen may only be half of the other prime-boost regimens, making this subunit + inactivated combination an attractive option.

Management of a novel strain of Riemerella Anatipestifer isolated from mandarin ducks (Aix Galericulata) in Australia

“…Mixed infections due to poor cross‐protection between RA serotypes may lead to apparent changes in serotype within populations 7 . Despite the ongoing development of vaccine technology, the scope for small institutions to formulate autologous vaccines is likely to be limited 9 …”

“…7 Despite the ongoing development of vaccine technology, the scope for small institutions to formulate autologous vaccines is likely to be limited. 9 Antibiotic treatment with tetracycline was pursued in the presented cases due to the potential for future contact with naïve Anseriformes at the receiving institution. Antibiotic selection was based on sensitivity testing and contrasts with previous reports describing poor efficacy of tetracyclines in RA-infected White Pekin ducks.…”

Faecalibacter bovis sp. nov., isolated from cow faeces

“…Most type species of the genera in the family were isolated from humans [1–5] and animals [6–10]. Some species in the family, such as Empedobacter brevis [11], Elizabethkingia anopheles [12], Riemerella anatipestifer [13], Ornithobacterium rhinotracheale [14], Bergeyella zoohelcum [15], Chryseobacterium meningosepticum [16] and Weeksella virosa [17] are important pathogens of animals and/or humans. In the present study, an unusual Gram-stain-negative, pleomorphic rod-shaped bacterium, designated ZY171143 T , was isolated from faeces of a cow with acute diarrhoea, in Yunnan Province, south-west PR China.…”

In Silico Analysis and Immune Response of YaeT Protein Against Riemerella anatipestifer in Ducks

“…Because of the weak cross-immunity protection among RA serotypes, inactivated vaccines and attenuated vaccines must be based on the local serotypes of RA . OmpA protein was used to prepare RA subunit vaccine, but its immune protection was inconsistent [ 32 , 33 , 35 ].…”