Prevention of Salmonella enteritidis infection in commercial ducklings by oral chicken egg-derived antibody alone or in combination with probiotics

Department of Veterinary Pathology, College of Veterinary Medicine, Michigan State University, East Lansing 48824, USA. fulton@ahdl.msu.edu

Ducklings were given egg-derived antibody against Salmonella enteritidis (Ab) in drinking water daily to determine if infection could be prevented. Pekin ducklings in all experimental groups were infected on Day 1 or 5 with 0.7 x 10(6) Salmonella enteritidis (SE). Spleen, liver, and intestine of each bird were collected and cultured on Days 7, 14, 21, and 28. Only livers and spleens were culture positive for SE. Ducklings infected on Day 1 had more SE infections than controls at each observation. Ducklings infected on Day 5 had fewer SE infections than controls on Days 7, 14, and 21. The same experiment was repeated to determine if SE infection could be prevented under production conditions. Only 10 ducks per group were infected with 1.02 x 10(7) SE. In addition to Ab, one group each, infected on Day 1 or 5, received a proprietary probiotic (Pro) daily to determine if Pro was synergistic to Ab. Groups receiving Ab and Pro and infected on Day 1 had fewer birds infected than Ab alone in Day 1-infected birds. Both Day 1-infected groups had more birds infected than controls. Birds infected on Day 5 had fewer ducks infected than controls on Days 7, 14, and 21. Except for Day 14, birds receiving both Ab and Pro and infected on Day 5 had fewer birds infected than Ab alone on Day 21 and 28. Probiotics act synergistically with oral Ab. Oral antibodies may serve as a tool to prevent salmonella infection in poultry.