Salmonella survival in manure-treated soils during simulated seasonal temperature exposure
Salmonella survival in manure-treated soils during simulated seasonal temperature exposure
复制标题
DOI：
10.2134/jeq2005.0449
复制
发表时间：
2006-07-01
影响因子：
2.4
通讯作者：
Blank, Gregory
中科院分区：
文献类型：
--
作者：
Holley, Richard A.;Arrus, Katia M.;Blank, Gregory
向土壤中添加动物粪便可以为土壤，水和食品的沙门氏菌污染提供机会。本研究探讨了暴露于不同的模拟季节性温度序列的猪粪处理的壤土砂和粘土如何影响沙门氏菌的生存时间。将沙门氏菌血清型（Agona、Hadar、Heidelberg、Montevideo、Oranienburg和Typhimurium）的六菌株混合物直接加入约5 kg两种土壤中，以产生5 log cfu/g，并将水分调节至田间容量（FC）的60或80%。类似地，将沙门氏菌混合物与来自猪保育棚的新鲜粪肥浆料混合，并将后者以25 g/kg添加到两种土壤中以获得5 log cfu/g沙门氏菌。将粪肥在整个土壤中混合或与最上面的一公斤土壤混合，并将整个土壤体积调节至60或80%FC。土壤处理在代表冬至夏（-18，4，10，25 ℃）、春至夏（4，10，25，30 ℃）或夏至冬（25，10，4，-18 ℃）季节性周期的温度序列下储存180 d，每个温度步骤持续45 d。在接种后0、7和15 d以及此后每隔15 d至180 d采集样品，通过直接平板接种或富集进行沙门氏菌回收。沙门氏菌的数量减少，在应用到土壤中，最大的下降发生在第一周。较高的土壤湿度，粪肥添加，并在一天的土壤中储存增加沙门氏菌的生存。沙门氏菌存活时间最长（180天），在这两种土壤中，在夏季和冬季曝光，但160天后，暴露于其他季节性处理的壤土砂土中没有分离出来。对于除一种治疗外的所有治疗，从给药后前45天计算的十进制减少时间（DRT 45 d）值为
Addition of animal manure to soil can provide opportunity for Salmonella contamination of soil, water, and food. This study examined how exposure of hog manure-treated loamy sand and clay soils to different simulated seasonal temperature sequences influenced the length of Salmonella survival. A six-strain cocktail of Salmonella serovars (Agona, Hadar, Heidelberg, Montevideo, Oranienburg, and Typhimurium) was added to yield 5 log cfu/g directly to about 5 kg of the two soils and moisture adjusted to 60 or 80% of field capacity (FC). Similarly, the Salmonella cocktail was mixed with fresh manure slurry from a hog nursery barn and the latter added to the two soils at 25 glkg to achieve 5 log cfu/g Salmonella. Manure was mixed either throughout the soil or with the top kilogram of soil and the entire soil volume was adjusted to 60 or 80% FC. Soil treatments were stored 180 d at temperature sequences representing winter to summer (-18, 4, 10, 25 degrees C), spring to summer (4,10,25,30 degrees C), or summer to Winter (25, 10, 4, -18 degrees C) seasonal periods with each temperature step lasting 45 d. Samples for Salmonella recovery by direct plating or enrichment were taken at 0, 7, and 15 d post-inoculation and thereafter at 15-d intervals to 180 d. Salmonella numbers decreased during application to soil and the largest decreases occurred within the first week. Higher soil moisture, manure addition, and storage in the day soil increased Salmonella survival. Salmonella survived longest ( 180 d) in both soils during summer-winter exposure but was not isolated after 160 d from loamy sand soil exposed to other seasonal treatments. For all but one treatment decimal reduction time (DRT45d) values calculated from the first 45 d after application were