Effects of Chronic Ingestion of Ochratoxin A on Blood Levels and Excretion of the Mycotoxin in Sheep
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- 作者：Ralf Blank ; Jan-Peter Rolfs ; Karl-Heinz Sü ; dekum ; Andrew A. Frohlich ; Ronald R. Marquardt ; and Siegfried Wolffram
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2003
- 出版时间：November 5, 2003
- 年：2003
- 卷：51
- 期：23
- 页码：6899 - 6905
- 全文大小：83K
- 年卷期：v.51,no.23(November 5, 2003)
- ISSN：1520-5118
文摘
Ruminants are relatively resistant to the acutely toxic effects of ochratoxin A, due to extensivedegradation of ochratoxin A to its less toxic metabolite ochratoxin 
by rumen microorganisms.However, most estimates of the degradation capacity for ochratoxin A in ruminants are based on invitro studies. In the current study, the metabolism of ochratoxin A was investigated over a period of29 days, feeding various doses of the mycotoxin (0, 9.5, 19.0, and 28.5 
g ochratoxin A/kg bodyweight) to sheep. Animals were fed diets consisting of 70% concentrates and 30% grass silage.Significant concentrations of undegraded ochratoxin A were detected in serum of sheep at all levelsof ochratoxin A tested. Serum concentrations of ochratoxin A slightly accumulated with time ofexposure and were linearly dependent on the administered dose of ochratoxin A. Furthermore, aconstant proportion (6-8%) of the dose was excreted in the urine. The results of this study indicatethat even at moderate to low levels of ochratoxin A in the diet, considerable amounts of the mycotoxinare absorbed by ruminants and may accumulate in tissues. Therefore, feeding of ochratoxinA-contaminated feedstuffs to ruminants does not seem to be a reliable means for using thesefeedstuffs.Keywords: Ochratoxin A; ochratoxin ; mycotoxin; sheep; ruminants; metabolism; excretion
by rumen microorganisms.However, most estimates of the degradation capacity for ochratoxin A in ruminants are based on invitro studies. In the current study, the metabolism of ochratoxin A was investigated over a period of29 days, feeding various doses of the mycotoxin (0, 9.5, 19.0, and 28.5 g ochratoxin A/kg bodyweight) to sheep. Animals were fed diets consisting of 70% concentrates and 30% grass silage.Significant concentrations of undegraded ochratoxin A were detected in serum of sheep at all levelsof ochratoxin A tested. Serum concentrations of ochratoxin A slightly accumulated with time ofexposure and were linearly dependent on the administered dose of ochratoxin A. Furthermore, aconstant proportion (6-8%) of the dose was excreted in the urine. The results of this study indicatethat even at moderate to low levels of ochratoxin A in the diet, considerable amounts of the mycotoxinare absorbed by ruminants and may accumulate in tissues. Therefore, feeding of ochratoxinA-contaminated feedstuffs to ruminants does not seem to be a reliable means for using thesefeedstuffs.Keywords: Ochratoxin A; ochratoxin ; mycotoxin; sheep; ruminants; metabolism; excretion