Gupta Tanushree B, Brightwell Gale
Food Assurance and Meat Quality, Hopkirk Research InstituteAgResearch Limited, Massey University Campus, Palmerston North, New Zealand.
Microbiologyopen. 2017 Aug;6(4). doi: 10.1002/mbo3.457. Epub 2017 Mar 3.
The aim of our study was to determine the occurrence and diversity of economically important spore-forming bacteria in New Zealand dairy farm systems. Farm dairy effluent (FDE) collected from Waikato dairy farms were tested for the presence of spore-forming bacteria, using a new culture-based methodology followed by genomic analysis. An enrichment step in which samples were inoculated in cooked meat glucose starch broth under anaerobic conditions, aided in the differential isolation of Bacillus and Clostridium species. Furthermore, the use of molecular methods such as ERIC genotyping, 16S rRNA gene sequence analysis identified different spore-forming bacteria present in FDE. C. sporogenes signature PCR gave further information on the phylogenetic relationship of the different Clostridium spp. isolated in this study. In total 19 Bacillus spp., 5 Paenibacillus spp. and 17 Clostridium spp. were isolated from farm dairy effluent. Sequence types similar to economically important food spoilage bacteria viz: C. butyricum, C. sporogenes and members of the Paenibacillus Genus were isolated from all four farms, whereas, sequence types similar to potential toxigenic, B. cereus, C. perfringens, C. butyricum, and C. botulinum were found on at least three of the farms. Sampling of farm dairy effluent provides a good indicator of farm level prevalence of bacterial load as it is used to irrigate dairy pasture in New Zealand. This study highlights the presence of various spore-forming bacteria in dairy waste water and indicates the implementation of good hygienic farm practices and dairy waste effluent management.
我们研究的目的是确定新西兰奶牛养殖系统中具有经济重要性的产芽孢细菌的发生情况和多样性。使用一种新的基于培养的方法并随后进行基因组分析，对从怀卡托奶牛场收集的农场奶牛废水（FDE）进行产芽孢细菌检测。在厌氧条件下将样品接种到熟肉葡萄糖淀粉肉汤中的富集步骤，有助于芽孢杆菌属和梭菌属物种的差异分离。此外，使用诸如ERIC基因分型、16S rRNA基因序列分析等分子方法，鉴定了FDE中存在的不同产芽孢细菌。梭状芽孢杆菌特征性PCR提供了关于本研究中分离的不同梭菌属物种系统发育关系的更多信息。总共从农场奶牛废水中分离出19种芽孢杆菌属、5种类芽孢杆菌属和17种梭菌属。从所有四个农场中都分离出了与具有经济重要性的食品腐败细菌相似的序列类型，即丁酸梭菌、产芽孢梭菌和类芽孢杆菌属成员，而在至少三个农场中发现了与潜在产毒的蜡样芽孢杆菌、产气荚膜梭菌、丁酸梭菌和肉毒梭菌相似的序列类型。农场奶牛废水采样是农场细菌负荷流行程度的一个良好指标，因为它在新西兰用于灌溉奶牛牧场。本研究突出了奶牛废水中存在各种产芽孢细菌，并表明需要实施良好的农场卫生措施和奶牛废水管理。
