Halls N A, Tallentire A
Lab Anim. 1978 Jan;12(1):5-10. doi: 10.1258/002367778780953378.
The numbers and types of microorganisms contaminating a commercially available laboratory animal diet were examined by plate-count methods at all stages of production. During the cooking and pelleting stages of manufacture there was a marked reduction in numbers of heat-labile vegetative contaminants introduced via the raw materials, and at subsequent stages plate counts at 37 and 25 degrees C corresponded closely to counts of viable aerobic bacterial endospores. It would seem that the count on the pelleted diet was determined principally by the numbers of bacterial spores being introduced with the ingredients. The response to gamma-irradiation of the innate microflora contaminating the pelleted diet was characteristic of that generally seen with populations of aerobic bacterial endospores.
通过平板计数法对市售实验动物饲料生产各阶段污染的微生物数量和类型进行了检测。在饲料加工的蒸煮和制粒阶段，通过原材料引入的热不稳定营养污染物数量显著减少，在随后的阶段，37℃和25℃下的平板计数与需氧细菌内生孢子的活菌计数密切相关。似乎制粒饲料上的计数主要由配料中引入的细菌孢子数量决定。污染制粒饲料的固有微生物群对γ射线照射的反应是需氧细菌内生孢子群体通常表现出的特征。
