Department of Veterinary Integrative Biosciences , College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA.
J Biol Dyn. 2012;6(2):1052-66. doi: 10.1080/17513758.2012.722232.
This study reports analysis of faecal shedding dynamics in cattle for three Escherichia coli O157:H7 (ECO157) strains (S1, S2 and S3) of different genotype and ecological history, using experimental inoculation data. The three strains were compared for their shedding frequency and level of ECO157 in faeces. A multistate Markov chain model was used to compare shedding patterns of S1 and S2. Strains S1 and S2 were detected seven to eight times more often and at 10(4) larger levels than strain S3. Strains S1 and S2 had similar frequencies and levels of shedding. However, the total time spent in the shedding state during colonization was on average four times longer for S1 (15 days) compared to S2 (4 days). These results indicate that an ECO157 strain effect on the frequency, level, pattern and the duration of faecal shedding may need to be considered in control of ECO157 in the cattle reservoir.
本研究报告了使用实验接种数据对三种不同基因型和生态史的大肠杆菌 O157:H7（ECO157）菌株（S1、S2 和 S3）在牛粪便中脱落动态的分析。比较了三种菌株在粪便中 ECO157 的脱落频率和水平。使用多状态马尔可夫链模型比较了 S1 和 S2 的脱落模式。与 S3 相比，S1 和 S2 菌株的检测频率高 7 至 8 倍，水平高 10（4）倍。S1 和 S2 菌株的脱落频率和水平相似。然而，在定植期间，S1（15 天）在粪便脱落状态下的总时间平均比 S2（4 天）长四倍。这些结果表明，在控制牛源 ECO157 时，可能需要考虑 ECO157 菌株对粪便脱落的频率、水平、模式和持续时间的影响。
