Use of 16S-rRNA based techniques to investigate the ecological succession of microbial populations in the immature lamb rumen:: Tracking of a specific strain of inoculated Ruminococcus and interactions with other microbial populations in vivo
Use of 16S-rRNA based techniques to investigate the ecological succession of microbial populations in the immature lamb rumen:: Tracking of a specific strain of inoculated Ruminococcus and interactions with other microbial populations in vivo
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DOI：
10.1007/s002489901006
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发表时间：
1999-11-01
影响因子：
3.6
通讯作者：
McSweeney, CS
中科院分区：
文献类型：
--
作者：
Krause, DO;Smith, WJM;McSweeney, CS
如果要使用微生物接种剂来控制瘤胃，在瘤胃中建立微生物是一个关键步骤。成熟瘤胃中的微生物种群经历了连续的变化，在不断变化的状态下，为特定菌株的引入提供了可能的机会。当羔羊的瘤胃发育成熟时，我们测量了几种具有16S-rRNA特异性寡核苷酸的微生物种群的变化：瘤胃球菌、纤维杆菌、真核生物、革兰氏阳性菌、拟杆菌-卟啉单胞菌-普雷沃氏菌群和厌氧瘤胃真菌。在这项研究中，我们用3.4 × 10(8)至0.8 × 10(9)的瘤胃球菌细胞剂量（-1）反复给15只羔羊注射，每周两次，持续7周，从23日龄到63日龄。在5株瘤胃球菌中（R. albus SY3和AR67， R. flavefaciens Y1、LP9155和AR72），菌株SY3的引物特异性最高（基于16S rDNA）。在给药过程中真核生物数量增加，推测原生动物的捕食导致了菌株SY3的消失。在给药结束时，PCR扩增显示SY3约为10(9)个细胞ml(-1)，但在给药后28 d内减少到PCR系统的检测限(8.6 × 10（4) ml(-1)）以下。这些实验表明，在给药期间，纤维溶解种群显著增加（P < 0.1），并在给药后数天内升高。这表明，高纤维分解细菌的剂量使更多的纤维为其他能够降解纤维的生物所利用，从而增加了瘤胃的整体纤维分解活性。革兰氏阳性细菌和拟杆菌-卟啉单胞菌-普雷沃氏菌群的继承检查显示，随着羔羊的成熟，相对丰度下降。
The establishment of microorganisms in the rumen is a critical step if rumen manipulation is to be accomplished by use of microbial inoculants. Microbial populations in the maturing rumen undergo successional changes and, while in a state of flux, provide a possible opportunity for the introduction of specific strains of bacteria. While the rumen of the young lamb was maturing, we measured changes in several microbial populations with 16S-rRNA specific oligonucleotides: Rumincoccus, Fibrobacter, eukaryotes, Gram-positive bacteria, the Bacteroides-Porphromonas-Prevotella group, and anaerobic rumen fungi. In this study we repeatedly dosed 15 lambs with approximately 3.4 x 10(8) to 0.8 x 10(9) Ruminococcus cells dose(-1), twice a week, for 7 wk from 23 d to 63 d of age. Of the five Ruminococcus strains dosed (R. albus SY3 and AR67, and R. flavefaciens Y1, LP9155, and AR72) the most specific primers (based on 16S rDNA) were obtained for strain SY3. There was an increase in the eukaryotic population during dosing, and it was hypothesized that protozoal predation contributed to the disappearance of strain SY3. At the end of dosing PCR amplification showed that SY3 were approximately 10(9) cells ml(-1), but decreased to below the detection limit of the PCR system (8.6 x 10(4) ml(-1)) within 28 d postdosing. These experiments showed that fibrolytic populations increased significantly (P < 0.1) above the controls during the dosing period and were elevated for several days postdosing. This suggests that dosing of highly fibrolytic bacteria makes more of the fiber available to other organisms able to degrade fiber, and in so doing increases the overall fibrolytic activity of the rumen. Examination of the succession of gram-positive bacteria and the Bacteroides-Porphromonas-Prevotella group showed a decline in relative abundance as the lambs matured.