Swords W E, Wu C C, Champlin F R, Buddington R K
Department of Biological Sciences, College of Veterinary Medicine, Mississippi State University 39762-5759.
Biol Neonate. 1993;63(3):191-200. doi: 10.1159/000243931.
The importance of the colonic microflora in health and nutrition is well known, but how they colonize and become established in the colon is not well understood. We therefore characterized the quantitative and qualitative changes of the colonic microflora during the first 120 days of postnatal development. Unlike previous studies, changes were defined for individual pigs using in situ samples collected anaerobically and aseptically from the distal colon. Although the colons were sterile at birth, they were rapidly colonized, and within 12 h bacterial densities had stabilized at 10(-9)-10(10) bacteria/g colonic content. Facultative anaerobes, notably coliforms, initially dominated the microflora, but were supplanted within 48 h after birth by obligate anaerobes, which constituted greater than 90% of the microflora thereafter. Bacteroides spp., the predominant anaerobes in the adult colon, did not markedly increase in abundance until after weaning and were still increasing by postnatal day 120. Shifts in the relative abundances of different bacterial populations throughout the first 120 days after birth confirm previous reports that the establishment of the adult colonic microflora is a gradual, sequential process, and highlight the need to focus research on anaerobic groups.
结肠微生物群在健康和营养方面的重要性已广为人知，但它们如何在结肠中定殖并建立群落却尚未得到充分了解。因此，我们对出生后120天内结肠微生物群的数量和质量变化进行了表征。与以往研究不同的是，本研究针对个体猪，使用从远端结肠厌氧无菌采集的原位样本确定变化情况。虽然出生时结肠是无菌的，但它们很快就被定殖，在12小时内细菌密度稳定在每克结肠内容物10^(-9)-10^(10)个细菌。兼性厌氧菌，特别是大肠菌，最初在微生物群中占主导地位，但在出生后48小时内被专性厌氧菌取代，此后专性厌氧菌占微生物群的比例超过90%。拟杆菌属，即成年结肠中的主要厌氧菌，直到断奶后其丰度才显著增加，到出生后第120天仍在增加。出生后前120天内不同细菌种群相对丰度的变化证实了先前的报道，即成年结肠微生物群的建立是一个渐进的、有序的过程，并突出了将研究重点放在厌氧菌群上的必要性。
