Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, China.
Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, China.
Front Immunol. 2019 Apr 2;10:666. doi: 10.3389/fimmu.2019.00666. eCollection 2019.
Probiotics have been used successfully to promote human and animal health, but only limited studies have focused on using probiotics to improve the health of hosts of different age. Canine microbiome studies may be predictive of results in humans because of the high structural and functional similarity between dog and human microbiomes. A total of 90 dogs were divided into three groups based on dog age (elderly group, = 30; young group, = 24; and training group, = 36). Each group was subdivided into two subgroups, with and without receiving daily probiotic feed additive. The probiotic feed additive contained three different bacterial strains, namely Zhang, P-8, and subsp. V9. Serum and fecal samples were collected and analyzed at four different time points, i.e., days 0, 30, and 60 of probiotic treatment, and 15 days after ceasing probiotic treatment. The results demonstrated that probiotics significantly promoted the average daily feed intake of the elderly dogs ( < 0.01) and the average daily weight gain of all dogs ( < 0.05), enhanced the level of serum IgG ( < 0.001), IFN-α ( < 0.05), and fecal SIgA ( < 0.001), while reduced the TNF-α ( < 0.05). Additionally, probiotics could change the gut microbial structure of elderly dogs and significantly increased beneficial bacteria (including some species and ) and decreased potentially harmful bacteria (including and ), and the elderly dogs showed the strongest response to the probiotics; the relative abundance of some of these species correlated with certain immune factors and physiological parameters, suggesting that the probiotic treatment improved the host health and enhanced the host immunity by stimulating antibody and cytokine secretion through regulating canine gut microbiota. Furthermore, the gut microbiota of the elderly dogs shifted toward a younger-like composition at day 60 of probiotic treatment. Our findings suggested that the probiotic treatment effects on canine health and immunity were age-related and have provided interesting insights into future development of probiotic-based strategies to improve animal and human health.
益生菌已成功用于促进人类和动物健康，但只有有限的研究关注使用益生菌来改善不同年龄宿主的健康。由于犬科微生物组和人类微生物组在结构和功能上高度相似，犬科微生物组的研究可能具有预测人类结果的潜力。总共将 90 只狗分为三组，根据狗的年龄（老年组， = 30；年轻组， = 24；和训练组， = 36）。每组分为两个亚组，一个给予每日益生菌饲料添加剂，另一个不给予。益生菌饲料添加剂含有三种不同的细菌菌株，即 Zhang、P-8 和 subsp. V9。在益生菌治疗的第 0、30、60 天和停止益生菌治疗后的 15 天，采集血清和粪便样本并进行分析。结果表明，益生菌显著促进了老年犬的平均每日采食量（ < 0.01）和所有犬的平均日增重（ < 0.05），提高了血清 IgG（ < 0.001）、IFN-α（ < 0.05）和粪便 SIgA（ < 0.001）水平，同时降低了 TNF-α（ < 0.05）。此外，益生菌可以改变老年犬的肠道微生物结构，显著增加有益菌（包括一些 属和 种），减少潜在有害菌（包括 和 ），老年犬对益生菌的反应最强；其中一些物种的相对丰度与某些免疫因子和生理参数相关，表明益生菌治疗通过调节犬肠道微生物群刺激抗体和细胞因子分泌，改善了宿主健康，增强了宿主免疫力。此外，老年犬的肠道微生物群在益生菌治疗的第 60 天向更年轻的组成转变。我们的研究结果表明，益生菌对犬健康和免疫的作用与年龄相关，并为未来开发基于益生菌的策略以改善动物和人类健康提供了有趣的见解。
