ABSORPTION AND METABOLISM OF NIVALENOL IN PIGS

The absorption and metabolism of nivalenol (NIV) were studied in pigs fed 0.05 mg NIV/kg BW, twice daily. Blood samples were taken during th e first and third day, through catheters in the hepatic portal Vein an d peripheral mesenteric artery. Nivalenol was detected in most of the earliest blood samples, taken twenty minutes after the start of feedin g. During 7.5 hrs after feeding, 11-43% of the NIV dose was absorbed. The systemic peak concentrations were 3-6 ng NIV/ml, mostly occurring 2.5-4.5 h after feeding. Sixteen hours after feeding, NIV was still be ing absorbed from the intestine, and the systemic concentrations were 1-3 ng NIV/ml. Nivalenol was mainly excreted in faeces, which containe d concentrations up to 3.2 mg NIV/kg. No metabolites of NIV were found in plasma, urine, and faeces, either as glucuronic acid or sulphate c onjugates, or as de-epoxy-NIV, indicating a lack of metabolism. The fe eding of NIV did not cause feed refusal, and measured clinical plasma parameters were within the normal ranges.