Susceptibility of calves to challenge with Salmonella typhimurium 4/74 and derivatives harbouring mutations in htrA or purE.
Salmonella typhimurium 4/74 is highly virulent for cattle after oral challenge, causing severe diarrhoea, which is sometimes associated with systemic spread of the micro-organism. Although susceptible to oral challenge, groups of cattle were found to be relatively resistant to subcutaneous challenge with this strain. The virulence of S. typhimurium 4/74 harbouring mutations in htrA and purE was also assessed in cattle. Although S. typhimurium 4/74 htrA and purE are attenuated following oral challenge in mice, cattle were highly susceptible to oral challenge with these mutants. As with the parent S. typhimurium 4/74 strain, cattle exhibited greater susceptibility to oral compared to subcutaneous challenge with S. typhimurium htrA and purE mutants. Following subcutaneous challenge with sublethal levels of S. typhimurium 4/74, calves produced significant levels of antibodies to S. typhimurium soluble extract. No correlation was detected between interferon gamma levels in sera and susceptibility to infection by any route. The concentrations of the acute-phase-associated protein haptoglobin were increased in the sera of five of six cattle inoculated subcutaneously, although increases in concentration were smaller in cattle inoculated orally.
Villarreal-Ramos
Bernardo
B
Institute for Animal Health, Compton, Berkshire RG20 7NN, UK1.
Manser
Jacquie M
JM
Institute for Animal Health, Compton, Berkshire RG20 7NN, UK1.
Collins
Robert A
RA
Institute for Animal Health, Compton, Berkshire RG20 7NN, UK1.
Chance
Victoria
V
Institute for Animal Health, Compton, Berkshire RG20 7NN, UK1.
Eckersall
David
D
Biochemistry Section, Glasgow Veterinary School, Bearsden Rd, Glasgow G61 1QH, UK2.
Jones
Phillip W
PW
Institute for Animal Health, Compton, Berkshire RG20 7NN, UK1.
Dougan
Gordon
G
Department of Biochemistry, Imperial College of Science, Technology and Medicine, London SW7 2AZ, UK3.
D000284:Administration, Oral; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D002262:Carboxy-Lyases / Q000235:genetics*; D002417:Cattle; D005798:Genes, Bacterial; D006242:Haptoglobins / Q000378:metabolism; D006360:Heat-Shock Proteins; D007279:Injections, Subcutaneous; D007371:Interferon-gamma / Q000097:blood; D008070:Lipopolysaccharides / Q000276:immunology; D008297:Male; D051379:Mice; D009154:Mutation; D033903:Periplasmic Proteins; D012481:Salmonella Infections, Animal / Q000097:blood / Q000209:etiology / Q000276:immunology; D012486:Salmonella typhimurium / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity*; D012697:Serine Endopeptidases / Q000235:genetics*; D014774:Virulence / Q000235:genetics
D000907:Antibodies, Bacterial; D006242:Haptoglobins; D006360:Heat-Shock Proteins; D008070:Lipopolysaccharides; D033903:Periplasmic Proteins; D007371:Interferon-gamma; C061682:DegP protease; D012697:Serine Endopeptidases; D002262:Carboxy-Lyases; C022378:phosphoribosylaminoimidazole carboxylase