Urinary and Serum Concentration of Deoxynivalenol (DON) and DON Metabolites as an Indicator of DON Contamination in Swine Diets

Abstract

Pig health is impaired and growth performance is reduced when exposed to deoxynivalenol (DON). The measurement of DON in individual feedstuffs and complete swine diets is variable because of the inconsistent distribution of mycotoxins in feed and the difficulties in obtaining representative samples. We investigated whether measuring DON and its metabolites in biological samples could be used as a predictor of DON ingestion by pigs. Blood samples were collected between 3 and 4 h after the morning meal and urine samples were quantitatively collected over a 24 h period on d 40 and 82 of the study to evaluate serum and urinary content of DON and DON metabolites (iso-deoxynivalenol, DON-3-glucuronide, DON-15-glcurunide, deepoxy-deoxynivalenol, iso-deepoxy-deoxynivalenol, deepoxy-deoxynivalenol-3-glucuronide, and deepoxy-deoxynivalenol-15-glucuronide). The intake of DON was positively correlated with urinary DON output. Similarly, there was an increase in serum DON level with increasing DON intake. Overall, it was found that DON intake correlated with DON concentration in urine and blood serum when samples were collected under controlled conditions. Analyzing DON levels in urine and blood serum could be used to predict a pig's DON intake.

Keywords: DOM; biomarkers; deoxynivalenol; iso-DON; metabolites; serum; urine.

Figure 1

Regression relationship between DON intake and the excretion of DON (A) and its metabolites (isoDON, (B); DON-3-GlcA, (C); DON-15-GlcA, (D); DOM-1, (E); DOM-3-GlcA, (F); DOM-15-GlcA, (G)) in urine over a 24 h period in pigs receiving DON-contaminated diets (1, 3 or 5 mg/kg). Points in the graph represent combined pig data from two time points [day 40 (grower phase) and day 82 (finisher phase); n = 10/treatment per time point]. Data are expressed as daily DON intake (μmol/d) and urinary excretion of DON and its metabolites (μmol/d). The equation and the coefficient of determination (R²) of the regression curve are for DON: y = 0.2667x − 0.339, R² = 0.81 at p < 0.001; DOM-1: y = 0.0107x + 0.0337, R² = 0.27 at p < 0.001; isoDON: y = 0.0208x − 0.0288, R² = 0.48 at p < 0.001; DON-3-GlcA: y = 0.1343x + 0.1302, R² = 0.75 at p < 0.001; DON-15-GlcA: y = 0.1499x − 0.0032, R² = 0.79 at p < 0.001; DOM-3-GlcA: y = 0.0168x − 0.0113, R² = 0.71 at p < 0.001; and DOM-15-GlcA: y = 0.0448x + 0.112, R² = 0.73 at p < 0.001.

Figure 2

Regression relationship between DON intake and DON concentration in serum after a single meal. The blood samples were obtained within 3 and 4 h after pigs received a DON-contaminated diet (1, 3, or 5 mg/kg). Points in the graph represent combined pig data from two time points [day 40 (grower phase) and day 82 (finisher phase); n = 10/treatment per time point]. Data are expressed as DON intake from a single meal and the serum DON concentration (ng/mL). The equation and the coefficient of determination (R²) of the regression curve are y = 1.45x + 2.1, R² = 0.77 at p < 0.05.