Location: Poultry Microbiological Safety Research
Title: Impact of Feeding Systems and Hatchery Vaccination Programs on Immune System Development, Salmonella Colonization, Clearance of E. Coli and Reproductive Traits In Broiler Breeder Pullets Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 22, 2011
Publication Date: July 16, 2011
Citation: Montiel, E., Wilson, J., Buhr, R.J., Cox Jr, N.A., Mclendon, B., Rigsby, L.L. 2011. Impact of Feeding Systems and Hatchery Vaccination Programs on Immune System Development, Salmonella Colonization, Clearance of E. Coli and Reproductive Traits In Broiler Breeder Pullets. Meeting Abstract. 11285 abstract number. Technical Abstract: Broiler breeder pullets from a single grandparent flock were vaccinated at 19 days of embryonation with Marek's vaccines HVT +SB1 or a Vector HVT + Infectious bursal disease (IBD) vaccine. The birds were placed in an experimental broiler breeder facility at the University of Georgia and fed ad libitum. At 2 weeks of age, the pullets were vaccinated with the HVT+IBD vector and the skip a day feeding program was started. The remaining 600 pullets were divided into 3 groups (200 pullets each) and fed one of the following programs: 1) skip a day; 2) every day in the feeder; or 3) every day on the floor. All birds received a conventional live plus inactivated broiler breeder pullet vaccination program. All birds were fed daily after light stimulation at 21 weeks of age. The group vaccinated in the hatchery with HVT+SB1 was fed on a skip a day program as well. The development of the immune system was measured by weekly bursa-to-body weight ratio, spleen weights and histopathology of the bursa, spleen and thymus between 2 and 17 weeks of age. Cellular immunity was measured by determining the colonization rate in various tissues after oral challenge with Salmonella Enteritidis and also by the time of clearance of E. coli after intravenous inoculation. Serum samples for antibody titers against Infectious Bursal Disease were collected every 4 weeks starting at 4 weeks of age from all groups to assess B cell function. Additionally, maternal antibodies were also measured in the progeny. The birds fed every day in the floor cleared E. coli faster and had less S. Enteritidis colonization after oral challenge. Salmonella Enteritidis colonization was lower in the spleen samples from birds that received the vector HVT+IBD vaccine in the hatchery as compared with the HVT+SB1-vaccinated group.