Monitoring of natural zearalenone contamination in feeds of cattle herds, with special focus on the effect on reproductive efficacy.

第一项研究的目的是：(1)研究在不同饲养条件下使用市售ELISA法测定牛尿玉米赤霉烯酮（ZEN）浓度的有效性，以监测农场饲料的自然污染；(2)研究在饲料中添加真菌毒素吸附剂（MA）产品对尿液ZEN浓度的影响。研究结果表明，测定尿液ZEN及其代谢物的浓度不仅可以在农场水平上监测牛饲料中的天然ZEN污染，还可以在体内评估添加了MA的饲料后的MA功能。玉米赤霉烯酮（ZEN）及其代谢物是重要的非甾体雌性真菌毒素，可引起家畜，特别是猪的生殖障碍。采用液相色谱-串联质谱法同时检测猪卵泡液（FF）中ZEN及其代谢产物α-玉米赤霉烯醇（α-ZOL）和β-玉米赤霉烯醇（β-ZOL）。10个卵巢内共存在卵泡（直径为60 ~ 6mm）的FF样品均检测到ZEN和α-ZOL，但未检测到β-ZOL。此外，在经β-葡萄糖醛酸酶/芳香基磺化酶预处理的样品中检测到ZEN和α-ZOL，而未经处理的样品中没有检测到ZEN和α-ZOL，这表明FF样品中含有葡萄糖醛酸结合形式的真菌毒素，由于葡萄糖醛酸化影响受体结合，可能对猪卵母细胞的危害较小。尽管如此，葡萄糖醛酸缀合形式的影响应该研究，在体外和体内。此外，在猪体外成熟和受精过程中，急性暴露于玉米赤霉烯酮（ZEN）对猪卵母细胞成熟、受精或精子穿透能力的影响进行了评估。先在含zen （0-1000μg/l）的成熟培养基中培养卵母细胞，然后受精。其次，将不含ZEN的体外成熟卵母细胞在含ZEN的受精培养基中受精。在1000μg/l ZEN的作用下，卵母细胞的成熟率和精子的穿透能力显著降低。然而，没有观察到卵母细胞退化和DNA断裂率的增加，也没有观察到正常和多精受精的减少。1000μg/l ZEN对精子穿透率没有影响，但对正常受精率和多精受精率均有积极影响。由此可见，猪卵母细胞在成熟期、受精期卵母细胞和精子急性暴露于高达1000μg/l的ZEN中，不会影响卵母细胞的生育能力。少

The aims of the first study were (1) to investigate the efficacy of measuring bovine urinary zearalenone (ZEN) concentrations by using a commercially available ELISA method in cattle kept under different feeding conditions to monitor the natural contamination of feeds at the farm level, and (2) to investigate the effects of supplementation of a mycotoxin adsorbent (MA) product in the feed based on urinary ZEN concentration. The findings indicate the usefulness of measuring concentrations of urinary ZEN and its metabolites not only for monitoring the natural ZEN contamination of cattle feed at the farm level but also for in vivo evaluation of MA function after supplementing feeds with MA.Zearalenone (ZEN) and its metabolites are important nonsteroidal estrogenic mycotoxins that cause reproductive disorders in domestic animals, especially pigs. The aim of the second study were to simultaneously detect ZEN and its metabolites α-zearalenol (α-ZOL) and β-zearalenol (β-ZOL) in porcine follic … More ular fluid (FF) by liquid chromatography-tandem mass spectrometry. ZEN and α-ZOL, but not β-ZOL, were detected in all pooled FF samples collected from coexisting follicles (diameter >6mm) within 10 ovaries. Furthermore, ZEN and α-ZOL were detected in samples pretreated with β-glucuronidase/arylsulfatase, but not in those left untreated, suggesting that the FF samples contained glucuronide-conjugated forms of the mycotoxins that may be less harmful to porcine oocytes due to glucuronidation affecting the receptor binding. Nonetheless, the effects of the glucuronide-conjugated forms should be studied, both in vitro and in vivo. Additionally, the influence of acute exposure to zearalenone (ZEN) on porcine oocyte maturation, fertilization, or sperm penetration ability during both in vitro maturation and fertilization was evaluated. First, oocytes were cultured in ZEN-containing (0-1000μg/l) maturation medium and then fertilized. Second, oocytes maturing in vitro without ZEN were fertilized in ZEN-containing fertilization medium. The maturation rates of oocytes and penetration ability of sperm decreased significantly in the presence of 1000μg/l of ZEN. However, neither increases in the rates of degeneration and DNA fragmentation of oocytes nor reductions in normal and polyspermic fertilization were observed. ZEN did not affect the sperm penetration rates, however, 1000μg/l ZEN had positive effects on normal and polyspermic fertilization rates. Therefore, it can be suggested that an acute exposure of porcine oocytes during maturation, and oocytes and sperm during fertilization to ZEN up to 1000μg/l may not affect the fertility of the oocytes. Less