Recombinant Live-Attenuated Vaccine for Veterinary Use.

Vaccination is essential for maintaining animal health, with priority placed on safety and cost effectiveness in veterinary use. The development of recombinant live-attenuated vaccines (RASVs) has enabled the construction of balanced lethal systems, ensuring the stability of plasmid vectors encoding protective antigens post-immunization. These vaccines are particularly suitable for production animals, providing long-term immunity against a range of bacterial, viral, and parasitic pathogens. This review summarizes the progress made in this field, with a focus on clinical trials demonstrating the efficacy and commercial potential of RASVs in veterinary medicine.