|Lott, Berry - MISSISSIPPI STATE UNIV|
|Pharr, G - MISSISSIPPI STATE UNIV|
Submitted to: Avian Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 27, 2004
Publication Date: March 15, 2005
Citation: Branton, S.L., Lott, B.D., Evans, J.D., Collier, S.D., Roush, W.B., Bearson, S.M., Bearson, B.L., Pharr, G.T. 2005. A self-propelled, constant speed spray vaccinator for commercial layer chickens. Avian Diseases. 49:147-151. Interpretive Summary: The commercial table egg sector of the poultry industry, like virtually all farming, is moving toward fewer but larger farms. Many of these farms have 14 chicken houses with each house containing about 75,000 birds. In order to protect the chickens numerous vaccines must be administered over the two year life of the birds. Modified leaf blowers have been used for vaccine administration but for a variety of reasons, relatively few birds receive sufficient vaccine to result in an immune reaction. The vaccine cost alone for a single vaccination of one house of birds is about $1,400.00; this does not include the labor cost. When the vaccine does not result in a sufficient immune response, the chickens must be re-vaccinated. In order to more uniformly vaccinate layer chickens, a self-propelled vaccinator was built which produces a more consistent and uniform vaccination. The vaccinator reduces manpower by 80% and time to vaccinate a house of chickens by 84%.
Technical Abstract: Vaccination of commercial layer chickens is labor intensive and often results in poor rates of seroconversion which, in turn, generally correlates with decreased flock uniformity and performance. Attempts to improve vaccinations include numerous variations of individual shop-built vaccinators in use by the layer industry. Each of these vaccinators has limitations which contribute to poor vaccinations. Major problems include the non-uniform speed of the applicator system and pressure fluctuations at the spray nozzles which contribute to sporadic dispersion of the vaccine as the vaccinator is pushed or carried past the cages. A battery-powered, self-propelled vaccinator was designed and constructed which operates at a constant speed with constant nozzle pressure. In field use, this vaccinator has resulted in both labor and time savings as well as improved vaccination results against Mycoplasma gallisepticum.