In order to search for economical,safe and effective probiotic feed additives,one strain of Lactobacillus was isolated and screened from intestines of healthy weaned piglets in Yulin City of Shaanxi Province,and identified through bacterial morphology observation,physiological and biochemical test and 16S rRNA gene homology analysis,followed by acid and choline salt resistance test as well as animal challenge test.The results showed that the isolate had the morphological and biochemical characteristics consistent with typical characteristics of Lactobacillus,and its 16S rRNA gene sequence was highly identical to Lactobacillus reuteri,with a similarity of above 99%;and the isolate was identified as Lactobacillus reuteri and named as YL006 based on the results of biochemical test.YL006 strain represented significant tolerance at pH 2.0 and bile salt with mass fraction of 0.2%;and all tested mice survived and grew well,with an increase in daily feed intake and weight gain compared to the control group.In conclusion,the isolated YL006 strain was excellent in acid and bile salt tolerance as well as growth status and safety,contributing to the growth of mice to a certain extent,with a potential to be used as a probiotic feed additive.
关键词
罗伊氏乳杆菌/分离鉴定/安全性评价/饲料添加剂
Key words
Lactobacillus reuteri/isolation and identification/safety evaluation/feed additive
维普
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