The degree of periparturient relaxation of immunity to gastrointestinal parasites has a nutritional basis, as overcoming protein scarcity through increased protein supply improves lactational performance, enhances local immune responses and reduces worm burdens. Herein lactating rats, re-infected with Nippostrongylus brasiliensis, are used to test the hypothesis that a similar and rapid improvement of immunity can be achieved through reducing nutrient demand at times of dietary protein scarcity. Reducing litter size from 12 to three pups during lactation resulted, as expected, in cessation of maternal body weight loss and increased pup body weight gain compared with dams which continued to nurse 12 pups. This increase in performance concurred with a rapid decrease in parasitism; within 3 days post nutrient reduction, a 87% reduction in the number of worm eggs found in the colon and 83% reduction in worm burdens was observed, which concurred with increased local immune responses, i.e. 70% more mast cells and 44% more eosinophils in the small intestinal mucosa, to levels similar to those in dams nursing three pups throughout. However, there were no concurrent changes in goblet cell hyperplasia, serum anti-N. brasiliensis-specific antibody levels or mRNA expression of IL-4, IL-10 or IL-13 in the mesenteric lymph nodes. To our knowledge the current study is the first to employ a litter reduction strategy to assess the rate of immune improvement upon overcoming nutrient scarcity in a non-ruminant host. These data support the hypothesis that periparturient relaxation of immunity to gastrointestinal nematodes can be reduced by restoring nutrient adequacy and, importantly, that this improvement can occur very rapidly.

中文翻译：

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通过减少哺乳动物的生殖努力来改善围产期对寄生虫的免疫力的放松。

围产期对胃肠寄生虫的免疫力的放松程度具有营养基础，因为通过增加蛋白质供应来克服蛋白质短缺可改善泌乳性能，增强局部免疫反应并减少蠕虫负担。在本文中，再次感染巴西日圆线虫的哺乳大鼠被用来测试以下假设：通过在膳食蛋白质缺乏时减少营养需求，可以实现类似且快速的免疫力提高。与继续喂养 12 只幼崽的母猪相比，在哺乳期间将一窝产仔数从 12 只幼崽减少到 3 只幼崽，正如预期的那样，母体​​体重停止下降，幼崽体重增加增加。性能的提高与寄生现象的迅速减少相一致。营养减少后3天内，观察到结肠中发现的蠕虫卵数量减少 87%，蠕虫负担减少 83%，这与局部免疫反应增加一致，即小肠粘膜中肥大细胞增加 70% 和嗜酸性粒细胞增加 44%，以水平与整个喂养三只幼崽的水坝相似。然而，杯状细胞增生、血清抗N没有同时发生变化。肠系膜淋巴结中 IL-4、IL-10 或 IL-13 的巴西特异性抗体水平或 mRNA 表达。据我们所知，目前的研究是第一个采用减少垃圾策略来评估克服非反刍动物宿主营养缺乏后免疫改善率的研究。这些数据支持这样的假设，即可以通过恢复营养充足来减少围产期对胃肠道线虫的免疫力的放松，并且，