|Purswell, Joseph - Jody|
Submitted to: Popular Publication
Publication Type: Popular Publication
Publication Acceptance Date: 9/25/2008
Publication Date: 10/1/2008
Citation: Branton, S.L., Leigh, S.A., Purswell, J.L. 2008. Recent Advances in Mycoplasma gallisepticum Vaccine Administration. Feed and Livestock Magazine 5(4):28-31.
Interpretive Summary: Mycoplasma gallisepticum (MG) is a bacteria which is virtually ubiquitous in the commercial table egg industry. It is responsible for losses of approximately 16 eggs per hen over a typical 45 week laying cycle. These egg losses alone are estimated to cost the industry $140 million annually. To combat the losses associated with MG, there are three live MG vaccines; none are ideal and each has specific strengths and weaknesses. One of these three vaccines must be eyedrop administered while the other two can be either eyedrop or spray administered. These latter two are available as freeze-dried products which must be rehydrated. The organism is extremely fastidious in its nutrient and environmental requirements and does not remain viable very long when outside the chicken host. There are many factors that impact the viability of the vaccine as it is being rehydrated and spray-applied. These include osmolarity, pH, pressure used to apply the vaccine, and water temperature; and this paper identifies the optimal conditions for the aforementioned factors as we currently understand them.
Technical Abstract: Application of live Mycoplasma gallisepticum vaccines to layer chickens generally occurs at 9 to 10 weeks of age. Mycoplasma organisms are extremely fastidious in the laboratory and difficult to grow. Very little attention has been accorded to optimizing parameters for vaccine administration in the field. These parameters include pH, osmolarity, temperature of the water used to rehydrate the vaccine and the water used to dispense the vaccine, as well as the pressure used in vaccine dispersal. Recently several of these factors have been identified and the specific parameter has been optimized. This paper serves to summarize those parameters.