Safety and efficacy of an aroA-deleted live vaccine against avian colibacillosis in a multicentre field trial in broilers in Morocco.

The safety and efficacy of an aroA-deleted live vaccine against avian colibacillosis (Poulvac(®) E. coli) was evaluated in broilers in a multicentre field trial. The trial sites consisted of 18 paired bird houses (randomly assigned to either the vaccination or the control treatment groups) located in 15 farms in three different regions of Morocco.

Efficacy and safety of cell-associated vaccines against Marek's disease virus grown in QT35 cells or JBJ-1 cells.

The Marek's disease virus (MDV) vaccine strain CVI 988 usually is grown in primary chicken embryo fibroblasts (CEFs). We found that the strains could be grown also in the QT35 and JBJ-1 cell lines to titers in the same range as in the CEFs. Both cell lines are fibroblast-like cell lines, which can be grown in flat-bottomed tissue-culture flasks, roller bottles, and on microcarriers.

Efficacy and safety of cell associated vaccines against Marek's disease virus grown in a continuous cell line from chickens.

The Marek's disease virus (MDV) vaccine strains CVI 988 and herpes virus of turkeys (HVT) strain FC126, usually are grown in primary chicken embryo fibroblasts (CEF). We found that the strains could be grown also in the so-called JBJ-1 cell line to titres in the same range as when chicken embryo fibroblasts were used. The JBJ-1 cell line is a fibroblast-like continuous chicken cell line, which can be grown in flat bottom tissue culture flasks, roller bottles and on micro carriers.

Association of serologic and protective responses of avian influenza vaccines in chickens.

A study was conducted to evaluate efficacy of inactivated, reverse genetics-based H5N3 avian influenza vaccines and the predictive ability of a vaccination/serology model for testing vaccine batches. Serologic response, protection against mortality, and protection against viral shedding from trachea and cloaca were assessed for vaccines prepared varying only in antigen content. When the birds were grouped according to serologic response, a clear association with protection could be seen.

Efficacy of inactivated vaccines against H5N1 avian influenza infection in ducks.

The current Asian H5N1 highly pathogenic avian influenza virus has spread over much of Asia and into Europe and Africa. As well as affecting village and commercial chicken operations in many South East Asian countries, it differs from past H5 avian influenza viruses in that it causes morbidity and mortalities in other domesticated birds, such as ducks and turkeys and in wild water birds. Effective vaccines that can prevent infection, as well as disease, and be used in a variety of avian species are needed for field use.

The immunogenicity and efficacy against H5N1 challenge of reverse genetics-derived H5N3 influenza vaccine in ducks and chickens.

H5N1 avian influenza viruses are continuing to spread in waterfowl in Eurasia and to threaten the health of avian and mammalian species. The possibility that highly pathogenic (HP) H5N1 avian influenza is now endemic in both domestic and migratory birds in Eurasia makes it unlikely that culling alone will control H5N1 influenza. Because ducks are not uniformly killed by HP H5N1 viruses, they are considered a major contributor to virus spread.