Molan A L, Waghorn G C, Min B R, McNabb W C
Nutrition Group, AgResearch, Grasslands Research Centre, Palmerston North, New Zealand.
Folia Parasitol (Praha). 2000;47(1):39-44. doi: 10.14411/fp.2000.007.
The effects of condensed tannins (CT) extracted from seven forages on the motility of the economically important nematode, Trichostrongylus colubriformis (Giles, 1892), were evaluated by using a larval migration inhibition (LMI) assay. The assay involved incubation of third stage (L3) exsheathed T. colubriformis larvae with CT extracted from Lotus pedunculatus, Lotus corniculatus, sulla (Hedysarum coronarium), sainfoin (Onobrychis viciifolia), Dorycnium rectum, Dorycnium pentaphyllum and dock (Rumex obtusifolius) and measurement of larval migration through nylon mesh with a 20 microm pore size. At 100 microg ml(-1), CT from L. pedunculatus, L. corniculatus, sulla, sainfoin, D. rectum, D. pentaphyllum and dock inhibited 20%, 10%, 15%, 25%, 28%, 32% and 27% of the larvae, respectively from passing through the sieves compared to controls (no CT added). At 1000 microg CT ml(-1), CT purified from D. pentaphyllum had the highest inhibitory activity (63%) against 1-month old larvae followed by sainfoin (59%), L. pedunculatus (57%), D. rectum (53%), dock (50%), sulla (40%) and L. corniculatus (37%). Seven-month old larvae were more sensitive to the action of CT than 1-month old larvae (P < 0.001). Addition of 2 microg polyethylene glycol ([PEG] per microg CT; to remove the effect of CT) eliminated 81-93% of the CT activity (P < 0.001) compared to incubations without PEG. The impact of CT on larval migration suggests a possible role for these plants in ruminant diets as a means to reduce dependence upon proprietary anthelmintics.
通过幼虫迁移抑制（LMI）试验，评估了从七种草料中提取的缩合单宁（CT）对经济上重要的线虫——蛇形毛圆线虫（Trichostrongylus colubriformis，Giles，1892）运动性的影响。该试验包括将脱鞘的蛇形毛圆线虫第三期（L3）幼虫与从莲座草（Lotus pedunculatus）、百脉根（Lotus corniculatus）、 sulla（Hedysarum coronarium）、红豆草（Onobrychis viciifolia）、直柄岩黄芪（Dorycnium rectum）、五叶岩黄芪（Dorycnium pentaphyllum）和酸模（Rumex obtusifolius）中提取的CT一起孵育，并测量幼虫通过孔径为20微米的尼龙网的迁移情况。与对照（未添加CT）相比，在100微克/毫升时，来自莲座草、百脉根、sulla、红豆草、直柄岩黄芪、五叶岩黄芪和酸模的CT分别抑制了20%、10%、15%、25%、28%、32%和27%的幼虫通过筛网。在1000微克CT/毫升时，从五叶岩黄芪中纯化的CT对1月龄幼虫的抑制活性最高（63%），其次是红豆草（59%）、莲座草（57%）、直柄岩黄芪（53%）、酸模（50%）、sulla（40%）和百脉根（37%）。7月龄幼虫比1月龄幼虫对CT的作用更敏感（P < 0.001）。与未添加聚乙二醇（[PEG]）的孵育相比，每微克CT添加2微克聚乙二醇（以消除CT的影响）消除了81 - 93%的CT活性（P < 0.001）。CT对幼虫迁移的影响表明，这些植物在反刍动物日粮中可能具有减少对专利驱虫药依赖的作用。
