The embodiments disclosed herein relate to the design, engineering and production of replication-deficient gene delivery vectors that are based on aviadenoviruses. More particularly their use is described in the transfer of genes, genetic engineering of cells and animals, the expression of proteins the development of vaccines. In some embodiment, the designs and packaging of partially deleted aviadenovirus vectors are disclosed. In other embodiments, the designs and packaging of fully deleted aviadenovirus vectors, the propagation of replication-deficient aviadenovirus vectors, and the characteristic and engineering of host cells are disclosed. In other embodiments, the use of such vectors in veterinary medicine is described.

A recombinant vaccine comprising a serotype 9 fowl adenovirus vector (FAdV-9) having at least one exogenous nucleotide sequence inserted encoding at least one antigen of a disease of interest and replacing the adenovirus genome non-essential region, and a pharmaceutically acceptable vehicle, adjuvant and/or excipient, wherein the at least one exogenous nucleotide sequence encoding at least one antigen of a disease of interest and replacing the adenovirus genome non-essential region is located between the 491 and 2782 nucleotides.

The vector of this vaccine is stable for industrial scale production. Likewise, even when administering this vaccine in combination with a vaccine against Marek's disease, both vaccines produce an adequate immune response which is not affected by interference between each other. In the same way, effectiveness of the recombinant vaccine is not affected by maternal antibodies, and is capable of inducing both an early and lasting protective response, even with only one application.

Disclosed herein are methods of performing continuous directed evolution in complex biological systems, including metazoan cells. These methods include the infection of engineered, non-naturally occurring metazoan cells with engineered, non-naturally occurring DNA viruses. The generation of infectious viruses that can infect new cells depends on the evolution of a gene of interest which is driven by an error-prone adenoviral polymerase. Also disclosed herein, are the compositions of engineered, non-naturally occurring metazoan cells and engineered, non-naturally occurring DNA viruses that function as components in the continuous directed evolution methodologies.

A recombinant vaccine comprising a serotype 9 fowl adenovirus vector (FAdV-9) having at least one exogenous nucleotide sequence inserted encoding at least one antigen of a disease of interest and replacing the adenovirus genome non-essential region, and a pharmaceutically acceptable vehicle, adjuvant and/or excipient, wherein the at least one exogenous nucleotide sequence encoding at least one antigen of a disease of interest and replacing the adenovirus genome non-essential region is located between the 491 and 2782 nucleotides. The vector of this vaccine is stable for industrial scale production. When administering this vaccine in combination with a vaccine against Marek's disease, both vaccines produce an adequate immune response which is not affected by interference between each other. In the same way, effectiveness of the recombinant vaccine is not affected by maternal antibodies, and is capable of inducing both an early and lasting protective response, even with only one application.

Disclosed herein are methods of performing continuous directed evolution in complex biological systems, including metazoan cells. These methods include the infection of engineered, non-naturally occurring metazoan cells with engineered, non-naturally occurring DNA viruses. The generation of infectious viruses that can infect new cells depends on the evolution of a gene of interest which is driven by an error-prone adenoviral polymerase. Also disclosed herein, are the compositions of engineered, non-naturally occurring metazoan cells and engineered, non-naturally occurring DNA viruses that function as components in the continuous directed evolution methodologies.