Agriculture and Agri-Food Canada, 5403 1st Avenue S., Lethbridge, Alberta T1J4B1, Canada.
Appl Environ Microbiol. 2010 Feb;76(4):1110-9. doi: 10.1128/AEM.01902-09. Epub 2009 Dec 18.
The persistence of naturally occurring campylobacteria in aerobic compost constructed of manure from beef cattle that were administered chlortetracycline and sulfamethazine (AS700) or from cattle not administered antibiotics (control) was examined. Although there were no differences in population sizes of heterotrophic bacteria, the temperature of AS700 compost was more variable and did not become as high as that of control compost. There were significant differences in water content, total carbon (C), total nitrogen (N), and electrical conductivity but not in the C/N ratio or pH between the two compost treatments. Campylobacteria were readily isolated from pen manure, for up to day 15 from control compost, and throughout the active phase of AS700 compost. Campylobacter DNA (including Campylobacter coli, Campylobacter fetus, Campylobacter hyointestinalis, and Campylobacter jejuni) was detected over the ca. 10-month composting period, and no reductions in quantities of C. jejuni DNA were observed over the duration of the active phase. The utilization of centrifugation in combination with ethidium monoazide (EMA) significantly reduced (>90%) the amplification of C. jejuni DNA that did not originate from cells with intact cell membranes. No differences were observed in the frequency of Campylobacter DNA detection between EMA- and non-EMA-treated samples, suggesting that Campylobacter DNA amplified from compost was extracted from cells with intact cell membranes (i.e., from viable cells). The findings of this study indicate that campylobacteria excreted in cattle feces persist for long periods in compost and call into question the common belief that these bacteria do not persist in manure.
研究了在有氧堆肥中，添加了曾被金霉素和磺胺甲基嘧啶（AS700）处理的肉牛粪便或未添加抗生素的牛的粪便（对照）后，自然产生的弯曲杆菌在有氧堆肥中的持久性。尽管异养细菌的数量没有差异，但 AS700 堆肥的温度变化更大，并且没有达到对照堆肥的温度。两种堆肥处理之间的水分含量、总碳（C）、总氮（N）和电导率存在显著差异，但 C/N 比和 pH 没有差异。从对照堆肥中，弯曲杆菌很容易从畜栏粪便中分离出来，直到第 15 天，并且在 AS700 堆肥的活跃阶段都可以分离到。在大约 10 个月的堆肥过程中，检测到弯曲杆菌 DNA（包括弯曲杆菌属、胎儿弯曲杆菌、空肠弯曲杆菌和空肠弯曲杆菌），并且在活跃阶段，未观察到空肠弯曲杆菌 DNA 数量的减少。在结合使用离心和吖啶橙单甲醚（EMA）时，显著减少了（>90%）来源于细胞膜完整的细胞的空肠弯曲杆菌 DNA 的扩增。在 EMA 和非 EMA 处理的样品之间，未观察到弯曲杆菌 DNA 检测频率的差异，这表明从堆肥中扩增的弯曲杆菌 DNA 是从细胞膜完整的细胞（即活细胞）中提取的。本研究的结果表明，在粪便中排泄的弯曲杆菌在堆肥中可以长时间存活，这对这些细菌不会在粪便中存活的普遍观点提出了质疑。
