Evaluation of safety and protection efficacy on cpxR and lon deleted mutant of Salmonella Gallinarum as a live vaccine candidate for fowl typhoid.
We evaluated a recently developed live fowl typhoid (FT) vaccine candidate, JOL916, the cpxR/lon mutant of Salmonella Gallinarum (SG), for safety and protection efficacy in 5-week-old layer chickens. Intramuscular vaccination with JOL916 revealed no or very few lesions in livers and spleens of the animals until the fourth week post-vaccination (wpv). This candidate clearly induced cellular immune responses in 5 of 5 chickens on the first and second wpv based on the peripheral lymphocyte proliferation assay. Systemic IgG responses were observed in 5 of 5 chickens from the first wpv and dramatic elevations were observed on the second and third wpv. Vaccination of chickens offered efficient protection against challenge by a wild-type SG; only slight anorexia and depression were temporarily observed after challenge in the vaccinated group while 100% mortality was observed in the positive control group. Body weight increases per day were slightly reduced between the 3rd and 6th day post challenge (dpc) compared to the negative control group; it was recovered from the 6th dpc. Collectively, these results demonstrate the safety and protective efficacy of JOL916 as a live vaccine for systemic FT.
College of Veterinary Medicine and Bio-Safety Research Institute, Chonbuk National University, Jeonju 561-756, Republic of Korea.
Kiku
K
Matsuda
Atul A
AA
Chaudhari
John Hwa
JH
Lee
D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000235:genetics*; D049109:Cell Proliferation; D002645:Chickens; D017353:Gene Deletion; D007074:Immunoglobulin G / Q000097:blood; D007273:Injections, Intramuscular; D008099:Liver / Q000473:pathology; D008214:Lymphocytes / Q000276:immunology; D011201:Poultry Diseases / Q000276:immunology / Q000401:mortality / Q000517:prevention & control*; D049070:Protease La / Q000172:deficiency*; D012481:Salmonella Infections, Animal / Q000276:immunology / Q000401:mortality / Q000517:prevention & control*; D022562:Salmonella Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000235:genetics / Q000276:immunology*; D019779:Salmonella enterica / Q000235:genetics / Q000276:immunology*; D013154:Spleen / Q000473:pathology; D016019:Survival Analysis; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000009:adverse effects / Q000235:genetics / Q000276:immunology
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D007074:Immunoglobulin G; D022562:Salmonella Vaccines; D014613:Vaccines, Attenuated; C085504:CpxR protein, Bacteria; D049070:Protease La