http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Evaluation of Vaccines on the Prevalence of Salmonella and/or Campylobacter in Layer and Broiler Chickens
The control of foodborne pathogens especially Salmonella and Campylobacter are of great concern to the commercial poultry industry. The control of these pathogens could be essential in the reduction of foodborne illness and deaths related to eggs and poultry meat. Previous studies have found that the presence or disappearance of Salmonella or Campylobacter is linked to various environmental and management-based factors, of which include vaccines used in the industry. Presently, we evaluated the effect of the infectious bronchitis virus (IBV) vaccine on the incidence of Salmonella or Campylobacter prevalence in broiler chicks. In the current study, a high vaccine dosage of IBV vaccine was associated with an increase the prevalence of Campylobacter during the first two weeks of age. Although in a previous study a high vaccine dose of IBV was linked in to increased prevalence of Salmonella, this was not seen in our study. In a subsequent trial, we also evaluated the potential cross-protection against three Salmonella serotypes of two-previously formulated vaccines when used in various dosage combinations. The combination vaccine was effective in reducing shedding of S. Enteritidis however reduction of S. Typhimurium and S. Hadar were not seen consistently. The vaccines were also shown to not significantly affect the body weights of the birds. Vaccines have been an essential component in the control of diseases within flocks in the commercial poultry industry. Ensuring the uniform application of IBV vaccine could help prevent and/or reduce the prevalence of Campylobacter in broiler flocks. The combination vaccine was effective against one serotype of Salmonella but further trials are needed to complete evaluate its potential as a vaccine that could be used in the poultry industry. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/151008
Master of Science Texas A & M University 2013 http://hdl.handle.net/1969.1/151008