Effects of stressors on immune parameters and on the faecal shedding of enterotoxigenic Escherichia coli in piglets following experimental inoculation.
The study examined the effects of stressors on the responses of 3 and a half-week old piglets that had been given an oral dose of enterotoxigenic Escherichia coli (ETEC) and a novel harmless antigen (ovalbumin). Removal from the sow (WEAN), a short-term cold stressor (12;C for 48 hours) (TEMP) and mixing with non-littermates (MIX) were assessed in terms of the effects on faecal shedding of ETEC, immune responses, weight gain and an ACTH stimulation test. WEAN and TEMP reduced weight gain and all stressors increased faecal shedding of ETEC. All stressors increased the IgG responses to F4(K88)ac antigens and WEAN and TEMP increased the IgA responses to the same antigens, probably as a result of increased intestinal proliferation of ETEC. None of the stressors, however, had significant effects on antibody responses to ovalbumin or on lymphocyte proliferation assays. The results indicate that stressors influence the faecal shedding of ETEC in young piglets by a mechanism that may not involve modulation of immune responses.
Jones
P H
PH
Division of Animal Health and Husbandry, Department of Clinical Veterinary Science, Langford House, University of Bristol, Langford, Bristol, BS40 5DU, UK.
Roe
J M
JM
Miller
B G
BG
D000324:Adrenocorticotropic Hormone; D000818:Animals; D000942:Antigens, Bacterial / Q000096:biosynthesis; D000954:Antigens, Surface / Q000276:immunology; D003080:Cold Temperature; D004926:Escherichia coli / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000276:immunology / Q000662:veterinary*; D029968:Escherichia coli Proteins; D005243:Feces / Q000382:microbiology*; D005260:Female; D036781:Fimbriae Proteins; D006799:Housing, Animal; D006854:Hydrocortisone / Q000097:blood; D007111:Immunity, Cellular; D007070:Immunoglobulin A / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008297:Male; D010047:Ovalbumin / Q000276:immunology; D013312:Stress, Physiological / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D013552:Swine; D013553:Swine Diseases / Q000276:immunology* / Q000382:microbiology; D013997:Time Factors; D014886:Weaning; D015430:Weight Gain
D000942:Antigens, Bacterial; D000954:Antigens, Surface; D029968:Escherichia coli Proteins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; C026888:K88 antigen, E coli; D036781:Fimbriae Proteins; D000324:Adrenocorticotropic Hormone; D010047:Ovalbumin; D006854:Hydrocortisone