|Pharr, G - MISSISSIPPI STATE UNIV|
Submitted to: Journal of Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 15, 2004
Publication Date: October 14, 2005
Citation: Evans, J.D., Leigh, S.A., Branton, S.L., Collier, S.D., Pharr, G.T., Bearson, S.M. 2005. Mycoplasma gallisepticum: current and developing means to control the avian pathogen. Journal of Applied Poultry Research. 14:757-763. Interpretive Summary: Mycoplasma gallisepticum (MG) is a major respiratory pathogen to poultry species (chickens and turkeys) worldwide. In the United States alone, economic losses associated with MG infections are significant and have exceeded $150 million annually. Current strategies to control against MG infections include intense biosecurity and biosurveillance practices with the turkey and broiler sectors of the poultry industry. Additionally, three attenuated strains of MG have been approved for use as vaccines in the egg layer industry. However, MG outbreaks still occur thereby necessitating the need for further means of MG control. Within this review, current research regarding novel MG vaccines is addressed.
Technical Abstract: Mycoplasma gallisepticum (MG) is a highly transmissible chicken and turkey pathogen and can result in significant performance and economic losses to poultry industries. Current control methods include stringent biosecurity and biosurveillance practices within the turkey and broiler sectors of the poultry industry. In addition, three live vaccines have been approved for use in the layer industry in the United States and have been demonstrated to reduce the production losses normally associated with MG infections. However, their use is currently restricted due to pathogenicity to turkeys and young broilers. Other problems with available vaccines include the induction of mild respiratory disease in treated layers and increased susceptibility to secondary pathogens. Cumulatively, these limitations have necessitated other means of MG control. Through application of molecular technologies, novel vaccines have been developed towards the control of numerous pathogens affecting a wide array of hosts. Recent advances in mycoplasma research including the development of genetic transformation/expression strategies and the identification of MG genes encoding surface antigens/colonization factors may afford the development of a recombinant MG vaccine. Expression of MG antigens/colonization factors in a commensal non-pathogenic mycoplasma species such as Mycoplasma gallinarum may provide a vaccine which is safe, cost effective, efficacious, applicable to all poultry, and easily identified via available techniques.