ETH Zurich, Institute of Plant, Animal and Agroecosystem Sciences, Zurich, Switzerland.
Theriogenology. 2010 Jul 15;74(2):173-83. doi: 10.1016/j.theriogenology.2010.01.028. Epub 2010 May 10.
Maca (Lepidium meyenii Walpers), is an Andean crop that grows between 3,800 and 4,500 m a.s.l. The persistent interest in this plant is based on its assumed effects on fertility of male mammals due to the prevalence of certain, partially specific, secondary compounds. The present study aimed at evaluating the effect of maca supplementation on quality and quantity of semen, mating behavior, and clinical status of peripubertal breeding bulls. The experiment followed a cross-over design lasting for 23 wk with 3 wk of adaptation and baseline measurements, and 2 x 10 wk of treatment feeding thus covering two times the complete 8-wk spermatogenic cycle. Seventy-eight 55 wk to 84 wk old breeding bulls received either no maca (control) or maca (233 mg dried hypocotyls/kg body weight/day) for 10 wk followed by 10 wk without maca (maca early) or maca only in the last 10 wk (maca late). Measurements were always made in the last 2 wk of each period. Apart from standard analyses, ejaculates were analyzed by flow cytometry. Data was evaluated by analysis of variance considering the repeated measurement structure of the data. Significant treatment by measurement period indicated direct or carry-over effects of maca. Maca supplementation had no direct effect on body weight, testes circumference, rectal temperature, mating behavior, and ejaculate volume. However, supplementing maca in the first 10 wk period increased the number of sperms in the second 10 wk period, i.e., when the animals no longer received maca. The DNA fragmentation index and the visually assessed motility of the sperms of bulls, that initially showed a borderline sperm quality, were significantly improved with early maca supplementation, while no such effect was observed in the two other groups. No effects occurred in the proportion of intact sperm plasma membranes or acrosomes or both. In conclusion, maca supplementation seems to improve sperm quantity and quality of bulls to a certain degree, while mating behavior appears unaffected.
玛卡（Lepidium meyenii Walpers）是一种安第斯作物，生长在海拔 3800 至 4500 米之间。由于某些特定的、部分特定的次生化合物的存在，这种植物被认为对雄性哺乳动物的生育能力有影响，因此人们对其一直保持着浓厚的兴趣。本研究旨在评估玛卡补充剂对青春期繁殖公牛精液质量和数量、交配行为以及临床状况的影响。该实验采用交叉设计，持续 23 周，包括 3 周的适应期和基线测量期，以及 2 x 10 周的处理喂养期，因此涵盖了完整的 8 周精子发生周期的两倍。78 头 55 至 84 周龄的繁殖公牛要么不接受玛卡（对照组），要么接受 233 毫克干下胚轴/公斤体重/天的玛卡，持续 10 周，然后不接受玛卡 10 周（玛卡早期）或仅在最后 10 周接受玛卡（玛卡晚期）。每次测量总是在每个周期的最后 2 周进行。除了标准分析外，还通过流式细胞术分析了精液。数据通过方差分析进行评估，考虑到数据的重复测量结构。处理与测量期间的显著相互作用表明玛卡有直接或后续作用。玛卡补充剂对体重、睾丸围度、直肠温度、交配行为和精液量没有直接影响。然而，在前 10 周补充玛卡增加了第 2 个 10 周的精子数量，即当动物不再接受玛卡时。最初精子质量处于边缘水平的公牛的精子 DNA 碎片化指数和视觉评估活力得到了显著改善，而其他两组则没有观察到这种效果。完整的精子质膜或顶体或两者的比例都没有变化。总之，玛卡补充剂似乎在一定程度上提高了公牛的精液数量和质量，而交配行为似乎不受影响。
