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

• Published in: Food additives and contaminants Vol. 23; no. 10; pp. 1008 - 1020
• Main Authors: Seeling, K, Danicke, S, Valenta,H, Egmond, H.P. van, Schothorst, R.C, Jekel, A.A, Lebzien, P, Schollenberger, M, Razzazi-Fazeli, E, Flachowsky, G
• Format: Journal Article
• Language: English
• Published: London Taylor & Francis Group 01.10.2006; Taylor & Francis
• Subjects: Animal Feed - analysis; Animals; Biological and medical sciences; Biotransformation; carry-over; Cattle - metabolism; cattle feeding; Cereal and baking product industries; cross contamination; dairy cows; Deoxynivalenol; Duodenum - metabolism; Feces - chemistry; feed contamination; feed intake; Female; Food Analysis - methods; food contamination; Food Contamination - analysis; Food industries; Fundamental and applied biological sciences. Psychology; Fusarium; General aspects; Hygiene and safety; level of feed intake; milk; Milk - chemistry; ruminants; toxigenic strains; Trichothecenes - administration & dosage; Trichothecenes - analysis; Trichothecenes - pharmacokinetics; Triticum - chemistry; Triticum aestivum; wheat; zearalenone; Animal feeding; Mycotoxin; Dairy cattle; Vomitoxin; Dairy product; ruminants; Deoxynivalenol; carry-over; Fungi; Toxin; Vertebrata; level of feed intake; Mammalia; Food intake; Biotransformation; Fusarium; Cereal; Artiodactyla; Fungi Imperfecti; Wheat; Ungulata; Thallophyta; Milk
• ISSN: 0265-203X; 1464-5122
• DOI: 10.1080/02652030600723245

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 μg and between 14 and 104 μg, 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.