title: Lawsonia intracellularis: humoral immune response and fecal shedding in weanling foals following intra-rectal administration of frozen-thawed or lyophilized avirulent live vaccine.
abstract: The humoral immune response and fecal shedding of Lawsonia intracellularis was investigated in 20 weanling foals following intra-rectal administration of frozen-thawed or lyophilized avirulent live L. intracellularis vaccine. Foals received either 30 mL frozen-thawed or lyophilized vaccine intra-rectally, given twice, 4 weeks apart. Serum samples from each foal were collected every 4 weeks for 16 weeks following the first vaccination and tested for anti-L. intracellularis specific IgG by immunoperoxidase monolayer assay. Rectal swabs were collected every other day following the first vaccination for 4 weeks for detection of L. intracellularis by real-time PCR. Both vaccine formulations administered intra-rectally in weanling foals were safe and led to similar onset and duration of fecal shedding and measurable serum IgG response against L. intracellularis.
authors.affiliation: Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA. npusterla@ucdavis.edu
authors.forename: Nicola
authors.initials: N
authors.lastname: Pusterla
authors.forename: Ryan
authors.initials: R
authors.lastname: Jackson
authors.forename: Samantha M
authors.initials: SM
authors.lastname: Mapes
authors.forename: Jayme
authors.initials: J
authors.lastname: Noland
authors.forename: Robert M
authors.initials: RM
authors.lastname: Stenbom
authors.forename: Connie
authors.initials: C
authors.lastname: Gebhart
mesh_terms: D000285:Administration, Rectal; D000818:Animals; D000831:Animals, Newborn; D000907:Antibodies, Bacterial / Q000097:blood; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000737:chemistry*; D045824:Desulfovibrionaceae Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D005243:Feces / Q000382:microbiology*; D005260:Female; D005612:Freeze Drying; D005615:Freezing; D006734:Horse Diseases / Q000276:immunology* / Q000517:prevention & control; D006736:Horses; D056724:Immunity, Humoral; D020639:Lawsonia Bacteria / Q000276:immunology*; D008297:Male; D014611:Vaccination / Q000379:methods / Q000662:veterinary; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000737:chemistry
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D014613:Vaccines, Attenuated