Prelusky D B, Scott P M, Trenholm H L, Lawrence G A
Animal Research Centre, Agriculture Canada, Ottawa, Ontario.
J Environ Sci Health B. 1990 Feb;25(1):87-103. doi: 10.1080/03601239009372678.
Milk and plasma levels of zearalenone (ZEN), alpha-zearalenol (alpha-ZEL), beta-zearalenol (beta-ZEL) and conjugated metabolites were determined after feeding lactating cows with ZEN. In those instances where ZEN and alpha- and beta-ZEL were detected in milk or plasma, they occurred only as conjugates hydrolysable by treatment with a mixture of beta-glucuronidase and aryl sulfatase. With studies where 50 or 165 mg was fed daily to three cows for 21 day periods, neither dosage showed the presence of ZEN or metabolites in either milk or plasma (detection limits: milk, 0.5 ng/ml, ZEN, alpha-ZEL; 1.5 ng/ml, beta-ZEL; plasma, 2-3 times higher). A dose of 544.5 mg zearalenone per day given to a single cow for 21 days yielded maximum concentrations of only 2.5 ng ZEN/ml and 3.0 ng alpha-ZEL/ml in the milk. In plasma, up to 3 ng ZEN/ml could be detected during the initial 4 days of treatment. At a dose of 1.8 g of zearalenone given over a one day feeding period, maximum milk levels of 4.0 ng ZEN/ml, 1.5 ng alpha-ZEL/ml, and 4.1 ng beta-ZEL/ml were observed during the initial 2 days; corresponding maximum levels after a one day dose of 6.0 g zearalenone were 6.1, 4.0 and 6.6 ng/ml milk on days 2-3. In plasma, peak ZEN concentrations (9 and 13 ng/ml at the lower and higher one-day doses, respectively) occurred 12 hr after initial dosing, and declined to negligible levels by days 5-7. Neither alpha- nor beta-ZEL were detected in plasma. Since measurable levels required very high oral doses of ZEN, milk would not normally pose a human health hazard as a result of feeding rations containing ZEN to lactating dairy cows.
给泌乳奶牛饲喂玉米赤霉烯酮（ZEN）后，测定了牛奶和血浆中玉米赤霉烯酮（ZEN）、α-玉米赤霉醇（α-ZEL）、β-玉米赤霉醇（β-ZEL）及其共轭代谢物的含量。在牛奶或血浆中检测到ZEN以及α-和β-ZEL的情况下，它们仅以可被β-葡萄糖醛酸酶和芳基硫酸酯酶混合物处理水解的共轭物形式存在。在对三头奶牛进行为期21天、每天分别饲喂50或165毫克的研究中，两种剂量下牛奶或血浆中均未检测到ZEN或代谢物（检测限：牛奶中，ZEN、α-ZEL为0.5纳克/毫升，β-ZEL为1.5纳克/毫升；血浆中，检测限高2至3倍）。每天给一头奶牛饲喂544.5毫克玉米赤霉烯酮，持续21天，牛奶中ZEN的最高浓度仅为2.5纳克/毫升，α-ZEL为3.0纳克/毫升。在血浆中，治疗的最初4天内可检测到高达3纳克/毫升的ZEN。在一天的饲喂期内给予1.8克玉米赤霉烯酮的剂量时，最初2天牛奶中ZEN的最高水平为4.0纳克/毫升、α-ZEL为1.5纳克/毫升、β-ZEL为4.1纳克/毫升；在一天给予6.0克玉米赤霉烯酮的剂量后，第2 - 3天牛奶中相应的最高水平分别为6.1、4.0和6.6纳克/毫升。在血浆中，ZEN的峰值浓度（较低和较高的一日剂量分别为9和13纳克/毫升）在初次给药后12小时出现，并在第5 - 7天降至可忽略不计的水平。血浆中未检测到α-或β-ZEL。由于可测量水平需要非常高的ZEN口服剂量，因此，给泌乳奶牛饲喂含ZEN的日粮通常不会使牛奶对人类健康构成危害。
