Effects ofFusariumtoxin-contaminated wheat and feed intake level on the biotransformation and carry-over of deoxynivalenol in dairy cows

Abstract

An experiment was carried out to examine the effects of feeding Fusarium toxin-contaminated wheat (8.21 mg deoxynivalenol (DON) and 0.09 mg zearalenone (ZON) per kg dry matter) at different feed intake levels on the biotransformation and carry-over of DON in dairy cows. For this purpose, 14 ruminal and duodenal fistulated dairy cows were fed a diet containing 60% concentrate with a wheat portion of 55% (Fusarium toxin-contaminated wheat (mycotoxin period) or control wheat (control period)) and the ration was completed with maize- and grass silage (50 : 50) on a dry matter basis. Daily DON intakes ranged from 16.6 to 75.6 mg in the mycotoxin period at dry matter intakes of 5.6-20.5 kg. DON was almost completely biotransformed to de-epoxy DON (94-99%) independent of the DON/feed intake, and the flow of DON and de-epoxy DON at the duodenum related to DON intake ranged from 12 to 77% when the Fusarium toxin-contaminated wheat was fed. In the serum samples, de-epoxy DON was detected in the range of 4-28 ng ml-1 in the mycotoxin period, while concentrations of DON were all below the detection limit. The daily excretion of DON and de-epoxy DON in the milk of cows fed the contaminated wheat varied between 1 and 10 microg and between 14 and 104 microg, respectively. The total carry-over rates as the ratio between the daily excretion of DON and de-epoxy DON into milk and DON intake were in the ranges of 0.0001-0.0002 and 0.0004-0.0024, respectively. Total carry-over rates of DON as DON and de-epoxy DON into the milk increased significantly with increasing milk yield. In the urine samples, de-epoxy DON was the predominant substance as compared with DON with a portion of the total DON plus de-epoxy DON concentration to 96% when the Fusarium toxin-contaminated wheat was fed, whereas the total residues of DON plus de-epoxy DON in faeces ranged between 2 and 18% of DON intake in the mycotoxin period. The degree of glucuronidation of de-epoxy DON was found to be approximately 100% in serum. From 33 to 80% of DON and from 73 to 92% of de-epoxy DON, and from 21 to 92% of DON and from 86 to 100% of de-epoxy DON were glucuronidated in the milk and urine, respectively. It is concluded that DON is very rapidly biotransformed to de-epoxy DON in the rumen and only negligible amounts of DON and de-epoxy DON were transmitted into the milk within the range of 5.6-20.5 kg day-1 dry matter intake and milk yields (fat corrected milk) between 10 and 42 kg day-1.

No carry over of unmetabolised deoxynivalenol in milk of dairy cows fed high concentrate proportions

“…In both periods of the present study, and independent of the concentrate proportion, DOM-1 was the predominant component found in the serum samples of cows fed the Fusarium toxin-contaminated diets. These results are in accordance with Seeling et al [2] who fed a ration with 60% concentrate and 3.9 mg DON/kg DM to 14 fistulated dairy cows over a period of 4 wk and detected DOM-1 concentrations between 4 and 28 ng/mL in the serum, but no unmetabolised DON. Accordingly Prelusky et al [5] found that less than 1% of DON were systemically absorbed in two cows fed a very high single oral dose of 1.9 mg pure DON/ kg BW (920 mg per animal).…”

“…The DON concentrations in the diets were, with 4.4 (Myco-30) and 4.6 mg/kg DM (Myco-60; Period 2) and 5.3 mg/kg DM (Period 1), respectively, higher than by Seeling et al [2] and this is reflected in higher DON and DOM-1 concentrations in the serum samples. DOM-1 concentrations were significantly linearly correlated with the DON intake (Fig.…”

The role of biomarkers in evaluating human health concerns from fungal contaminants in food

“…The intervention reduced wheat intake by . 90 %, and the urinary concentration of fD þ DG was also significantly (88) . This intervention restricted the types of food consumed rather than attempting to reduce the contamination level within the consumed food; thus readers should avoid a direct comparison of this outcome with that of the FB intervention above (82) .…”

Development and validation of a high performance liquid chromatographic–mass spectrometry method for the simultaneous quantification of 10 trichothecenes in ultra-high temperature processed cow milk

“…DON is mostly biotransformed within the rumen and detected in milk as DON and deepoxy-deoxynivalenol (DOM-1) [20][21][22], whereas T-2 has been detected in the milk without metabolization [23] and metabolized into HT-2, NEO, 4-deacetylneosolaniol, and 4 more unknown metabolites [24]. Metabolites could have different toxic effects than the parent mycotoxin [25,26].…”