Effects of combinations of ochratoxin A and T-2 toxin on immune function of yellow-feathered broiler chickens

• Published in: Poultry science Vol. 88; no. 3; pp. 504 - 510
• Main Authors: Wang, G.H, Xue, C.Y, Chen, F, Ma, Y.L, Zhang, X.B, Bi, Y.Z, Cao, Y.C
• Format: Journal Article
• Language: English
• Published: Oxford, UK Poultry Science Association 01.03.2009; Oxford University Press
• Subjects: Animals; body weight; broiler chickens; Bursa of Fabricius - drug effects; Chickens; dietary exposure; disease resistance; dosage; dose response; enzyme activity; Feathers; feed intake; Female; immune response; immunosuppression (physiological); Leukocytes - metabolism; lymphocytes; metabolism; Mitogens - metabolism; mixed infection; morphogenesis; mycotoxicosis; ochratoxin A; Ochratoxins - toxicity; oral administration; pathogenesis; poultry diseases; Poultry Diseases - chemically induced; Poultry Diseases - immunology; Spleen - drug effects; T-2 toxin; T-2 Toxin - toxicity; Thymus Gland - drug effects; T-2 toxin; chicken; ochratoxin A; immune response
• ISSN: 0032-5791; 1525-3171
• DOI: 10.3382/ps.2008-00329

The study was to investigate the effects of combinations of ochratoxin A (OTA) and T-2 toxin on immune function of yellow-feathered broiler chickens. Three-hundred sixty 21-d-old broiler chickens were randomly assigned to 3 groups, each group consisting of 4 duplicates each with 30 chickens. The 3 groups were fed the following diets for 3 wk: C, basal diet (control, mycotoxin-free); L, basal diet + 0.25 mg/kg of OTA, 0.5 mg/kg of T-2 toxin; and H, basal diet + 0.5 mg/kg of OTA, 1 mg/kg of T-2 toxin. Body weight and feed consumption of chickens in the H group decreased significantly (P < 0.05) during the study, but their efficiency of feed utilization was not affected. The feeding of OTA-T-2 toxin diets decreased not only the relative weight of spleen, thymus, and bursa of Fabricius, but also serum concentrations of total protein, albumin, and globulin. Meanwhile, the feeding of OTA-T-2 toxin diets elevated the activities of serum γ-glutamyltransferase, asparate aminotransferase, and alanine aminotransferase. The results of methyl thiazolyl tetrazolium reduction assay indicated that the mitogenic responses of peripheral blood lymphocytes were diminished significantly (P < 0.05 for L group; P < 0.01 for H group). Flow cytometry was employed to determine 3 indexes in peripheral blood lymphocyte of broilers, including CD4⁺/CD3⁺, CD8⁺/CD3⁺, and CD4⁺/CD8⁺. Both toxin treatments significantly decreased (P < 0.01) CD4⁺/CD3⁺ and CD4⁺/CD8⁺ ratios. In summary, the combination of OTA and T-2 toxin impaired chick immune function even at combined concentrations as low as 0.25 mg/kg of OTA and 0.5 mg/kg of T-2 toxin.