Location: Poultry Microbiological Safety Research
Title: Clearance of Escherichia coli After Intravenous Inoculation in Broiler Breeder Pullets Fed Skip a day, Every Day in the feeder and Every Day on the Litter Authors
Submitted to: Poultry Science Meeting
Publication Type: Abstract Only
Publication Acceptance Date: March 27, 2012
Publication Date: July 9, 2012
Citation: Montiel, E.R., Buhr, R.J., Cox Jr, N.A., Hofacre, C.L., Davis, A.J., Wilson, J.L. 2012. Clearance of Escherichia coli After Intravenous Inoculation in Broiler Breeder Pullets Fed Skip a day, Every Day in the feeder and Every Day on the Litter. Poultry Science Meeting. 91(Suppl. 1):18. p.8. Technical Abstract: The effect of feeding programs on the time of clearance of Escherichia coli in broiler breeder pullets was investigated. Broiler breeder pullets from a single grandparent flock were in ovo-vaccinated at 19 d of incubation with a vector HVT (vHVT) vector HVT + Infectious bursal disease (IBD) vaccine. The chicks were placed in an experimental pullet rearing facility at the University of Georgia or in a commercial pullet farm. The pullets were divided into 4 feeding program groups of approximately 200 birds each as follows: 1) skip a day (SAD) in two groups, one in the experimental facility and one in a commercial pullet farm; 2) every day in the trough feeder (EDT); 3) every day on the litter (EDL). All groups were fed daily after light stimulation at 22 wk and all birds received a conventional commercial broiler breeder pullet vaccination program. At 19, 22, 29, and 39 wk of age, groups of five birds were removed from the pens and inoculated intravenously with a 1 mL bacterial suspension containing 10^8cfu/mL of a pathogenic Escherichia coli strain. Blood samples were collected at 10, 20 and 60 min after inoculation and diluted 1:10, 1:100 and 1:1,000 using tryptose phosphate broth. Samples were spread plated onto McConkey agar and incubated at 37ºC for 24 h. The typical pink colonies were counted and colony forming units calculated per 1 mL of blood. The pullets fed EDF cleared Escherichia coli faster than the EDT and SAD groups at 19 wk of age and cfu counts decreased between 1,500 and 65,000, respectively. At 22 and 29 wk of age, there was no significant difference in the time of clearance among the groups fed SAD in the experimental facilities, those housed with the commercial flock, or the pullets fed EDL. However, the pullets fed EDT had consistently higher Escherichia coli counts than the rest of the groups at all of the blood sample times. These results suggest that feeding broiler breeder pullets on the litter may positively impact their ability to clear Escherichia coli from the vascular system.