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ENVIRONMENT, WELL-BEING, AND BEHAVIOR |

* Department of Veterinary Public Health and Food Science, Institute of Animal Nutrition, University of Veterinary Medicine, A-1210 Vienna, Austria; and
Institute for Veterinary Physiology, University of Leipzig, D-04103 Leipzig, Germany
1 Corresponding author: juergen.zentek{at}vu-wien.ac.at
Deoxynivalenol (DON) is a common mycotoxin contaminant in feedstuffs. It has been shown to cause diverse toxic effects in animals. The aim of the present study was to evaluate the effects of DON on the glucose transport capacity in chickens jejunum and to investigate the permeation of DON itself by the Ussing chamber technique. Glucose uptake into chicken jejunal epithelia was measured after the addition of 200 µmol/L of 14C-labeled glucose to the mucosal solution. Glucose uptake under control condition was 3.28 ± 0.53 nmol/cm2·min. The contribution of sodium glucose-linked transporter 1 (SGLT-1) to total glucose uptake was estimated by inhibiting SGLT-1 with phlorizin (100 µmol/L). In the presence of phlorizin, glucose uptake was reduced (P < 0.05) to 1.21 ± 0.19 nmol/cm2·min. Deoxynivalenol decreased (P < 0.05) the glucose uptake in the absence of phlorizin to 1.81 ± 0.24 nmol/cm2·min but had no additional effect on the glucose uptake in the presence of phlorizin (0.97 ± 0.17 nmol/cm2·min). Mucosal-to-serosal permeation of DON was proportional to the initial DON concentration over a concentration range from 1 to 10 µg/mL on the mucosal side. Apparent permeability at 10 µg/mL of DON measured 60 to 90 min after DON application was 1.7·1005 cm/s. It can be concluded that DON (10 mg/L) decreases glucose uptake almost as efficiently as phlorizin. The similarity between the effects of phlorizin and DON on glucose uptake evidences their common ability to inhibit Na+-D-glucose cotransport. In addition to local effects, DON can be absorbed from the jejunum. A predominant part of DON passes across the chicken intestinal epithelium by passive diffusion, which is likely on the paracellular pathway. The results imply that the exposure to DON-contaminated feeds may negatively affect animal health and performance by local (i.e., inhibition of intestinal SGLT-1) and systemic effects.
Key Words: laying hen deoxynivalenol Ussing chamber glucose absorption sodium glucose-linked transporter-1
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