de la Fuente Gabriel, Jones Eleanor, Jones Shann, Newbold Charles J
Departament de Ciència Animal, Escola Tècnica Superior d'Enginyeria Agrària, Universitat de LleidaLleida, Spain.
Institute of Biological Environmental and Rural Sciences, Aberystwyth UniversityAberystwyth, United Kingdom.
Front Microbiol. 2017 Jun 28;8:1194. doi: 10.3389/fmicb.2017.01194. eCollection 2017.
Stability in gut ecosystems is an important area of study that impacts on the use of additives and is related with several pathologies. Kefir is a fermented milk drink made with a consortium of yeast and bacteria as a fermentation starter, of which the use as additive in companion and livestock animals has increased in the last few years. To investigate the effect of kefir milk on foregut and hindgut digestive systems, an approach was followed. Either rumen fluid or horse fecal contents were used as a microbial inoculate and the inclusion of kefir (fresh, autoclaved, or pasteurized) was tested. Gas production over 72 h of incubation was recorded and pH, volatile fatty acids (VFAs), lactate and ammonia concentration as well as lactic acid (LAB) and acetic acid bacteria, and yeast total numbers were also measured. Both direct and indirect (by subtracting their respective blanks) effects were analyzed and a multivariate analysis was performed to compare foregut and hindgut fermentation models. Addition of kefir boosted the fermentation by increasing molar concentration of VFAs and ammonia and shifting the Acetate to Propionate ratio in both models but heat processing techniques like pasteurization or autoclaving influenced the way the kefir is fermented and reacts with the present microbiota. In terms of comparison between both models, the foregut model seems to be less affected by the inclusion of Kefir than the hindgut model. In terms of variability in the response, the hindgut model appeared to be more variable than the foregut model in the way that it reacted indirectly to the addition of different types of kefir.
肠道生态系统的稳定性是一个重要的研究领域，它影响添加剂的使用，并与多种病理状况相关。开菲尔是一种发酵乳饮料，由酵母和细菌的混合体作为发酵起始剂制成，在过去几年中，其作为伴侣动物和家畜添加剂的使用有所增加。为了研究开菲尔乳对前肠和后肠消化系统的影响，采用了一种方法。使用瘤胃液或马粪便内容物作为微生物接种物，并测试了开菲尔（新鲜、高压灭菌或巴氏杀菌）的添加情况。记录了72小时孵育期间的气体产生情况，并测量了pH值、挥发性脂肪酸（VFA）、乳酸和氨浓度以及乳酸菌（LAB）和醋酸菌以及酵母总数。分析了直接和间接（通过减去各自的空白值）效应，并进行了多变量分析以比较前肠和后肠发酵模型。添加开菲尔通过增加VFA和氨的摩尔浓度以及改变两种模型中的乙酸与丙酸比例来促进发酵，但巴氏杀菌或高压灭菌等热处理技术会影响开菲尔的发酵方式以及与现有微生物群的反应。在两种模型的比较方面，前肠模型似乎比后肠模型受开菲尔添加的影响更小。在反应的变异性方面，后肠模型在对不同类型开菲尔添加的间接反应方式上似乎比前肠模型更具变异性。
