title: Short-term exposure to subacute doses of aflatoxin-induced depressed mitogen responses in young mallard ducks.
abstract: Mallard ducklings were fed diets containing corn naturally contaminated with mixed aflatoxins, purified T-2 toxin, or no detectable mycotoxin in two trials. The aflatoxin level used was 12 ppb in the first trial and 33 ppb in the second. T-2 was added at 2 ppm in both trials. No pathology was associated with the aflatoxin used in this study, and T-2--induced lesions were described in a previous publication. The weights of primary (thymus and bursa of Fabricius) and secondary (spleen) lymphoid organs were significantly reduced in the T-2--treated birds. The total number of viable cells recovered from the thymus was significantly reduced in aflatoxin-treated birds. The numbers of viable cells recovered from thymus, bursa of Fabricius, and spleen were all significantly reduced after treatment with T-2. In each trial, significantly lower mitogenic responses were seen to pokeweed mitogen and concanavalin A in birds fed aflatoxin or T-2, representing reduction in both B-cell and T-cell mitogenesis. Birds fed aflatoxin also had significantly reduced Escherichia coli O55 lipopolysaccharide-induced mitogenic responses. These studies indicate that subacute oral exposure to aflatoxin caused a loss of normal lymphocyte reactivity in mallard ducklings. This finding supports the hypothesis that waterfowl that ingest even small quantities of mycotoxin-contaminated waste grain are likely to be more susceptible to bacterial or viral infections.
authors.affiliation: Department of Biology and Microbiology, South Dakota State University, Brookings 57007, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Hurley
authors.forename: R D
authors.initials: RD
authors.lastname: Neiger
authors.forename: K F
authors.initials: KF
authors.lastname: Higgins
authors.forename: G E
authors.initials: GE
authors.lastname: Rottinghaus
authors.forename: H
authors.initials: H
authors.lastname: Stahr
mesh_terms: D000348:Aflatoxins / Q000008:administration & dosage / Q000633:toxicity*; D000821:Animal Feed / Q000382:microbiology; D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D002060:Bursa of Fabricius / Q000166:cytology / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003208:Concanavalin A; D004372:Ducks / Q000276:immunology*; D005260:Female; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects*; D008221:Lymphoid Tissue / Q000166:cytology / Q000187:drug effects*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D037121:Plant Lectins; D011043:Pokeweed Mitogens; D013154:Spleen / Q000166:cytology / Q000187:drug effects; D013605:T-2 Toxin / Q000008:administration & dosage / Q000633:toxicity*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000187:drug effects; D003313:Zea mays / Q000382:microbiology
chemical_list: D000348:Aflatoxins; D008070:Lipopolysaccharides; D037121:Plant Lectins; D011043:Pokeweed Mitogens; D003208:Concanavalin A; D013605:T-2 Toxin