摘要
本研究旨在分离鉴定羊源酵母菌并评价其益生特性,为提高育肥羊的消化性能提供益生菌筛选来源。以育肥羊不同肠段和瘤胃的内容物为菌株分离的来源,通过初筛和溶血试验复筛获取安全菌株,对其进行形态学、生化鉴定并进行26S rDNA测序鉴定得到2株酿酒酵母菌,并评价其耐受性、抑菌能力和药敏性。选取益生效果好的酿酒酵母菌进一步进行体外瘤胃发酵试验,设7个添加不同剂量(1×10^(4)~1×10^(10) CFU/g)酿酒酵母菌的试验组和1个不添加菌株的对照组,体外发酵48 h,检测不同时间段的产气量和养分降解率。结果显示:从育肥羊盲肠中分离并鉴定出2株酿酒酵母菌Ma和Mb,其生长对数期均为6~16 h,且对人工胃液和人工肠液均具一定的耐受性,存活率均超过100%,且酿酒酵母菌Ma的存活率极显著高于酿酒酵母菌Mb(P<0.01)。另外,2株酿酒酵母菌对金黄色葡萄球菌和大肠杆菌均具有抑制性,且酿酒酵母菌Ma对这2种典型致病菌的抑菌圈直径均大于酿酒酵母菌Mb。从药敏特性分析,2株酿酒酵母菌对7种抗生素均具敏感性。酿酒酵母菌Ma的体外发酵结果表明,添加剂量为1×10^(7) CFU/g时48 h产气量最多,且此时干物质、粗蛋白质、中性洗涤纤维和酸性洗涤纤维降解率最高,均显著高于对照组(P<0.05)。综上可知,本试验从育肥羊盲肠中分离出的2株酿酒酵母菌均具有耐受胃肠液、抑菌能力强且对抗生素敏感的特性,且酿酒酵母菌Ma的体外发酵效果较好,可为饲用益生菌剂的开发提供优良菌种。
This study aimed to isolate and identify yeast strains from sheep and evaluate their probiotic characteristics,so as to provide a source for screening probiotics for improving the digestive performance of fattening sheep.The content of different intestinal segments and rumen of fattening sheep was used as the source of strain isolation,safe strains were obtained via primary screening and re-screening in hemolysis test,and then identified by these methods of morphological,biochemical identification,and 26S rDNA sequencing was performed.As a result,two strains of Saccharomyces cerevisiae were obtained.Three parameters including tolerance,bacteriostatic ability and drug sensitivity of identified strains above were also evaluated.Optimal strains above were selected for in vitro rumen fermentation test for 48 h.Seven test groups were designed with Saccharomyces cerevisiae doses of 1×10^(4) to 1×10^(10) CFU/g,and one control group was set without adding strain.Gas production and nutrient degradation rates were measured at different time intervals.The results showed that two strains of Saccharomyces cerevisiae Ma and Mb were isolated from the cecum with a growth logarithmic phase of 6 to 16 h,and demonstrated a certain tolerance to artificial rumen liquid and artificial intestinal fluid,with survival rates exceeding 100%.The survival rate of Saccharomyces cerevisiae Ma was extremely significantly greater than Saccharomyces cerevisiae Mb in both artificial rumen liquid and artificial intestinal fluid(P<0.01).In addition,both Saccharomyces cerevisiae Ma and Mb had some inhibited effects on two typical pathogenic bacteria(Staphylococcus aureus and Escherichia coli).Particularly,the Saccharomyces cerevisiae Ma exhibited a larger inhibition-zone diameter than Saccharomyces cerevisiae Mb.From the analysis of drug sensitivity characteristics,two strains of Saccharomyces cerevisiae were susceptible to seven antibiotics.Results from in vitro fermentation showed that the 48-h gas production was greater when Saccharomyces cerevisiae Ma additive dose was 1×10^(7) CFU/g,meanwhile,the degradation rates of dry matter,crude protein,neutral detergent fiber and acid detergent fiber for additive dose of 1×10^(7) CFU/g were the highest,and they were significantly greater than those of control group(P<0.05).In conclusion,the two Saccharomyces cerevisiae strains isolated form the cecum of fattening sheep in this experiment exhibit properties of tolerance to gastrointestinal fluids,strong bacteriostatic activity,and sensitivity to antibiotics,and the in vitro fermentation effect of Saccharomyces cerevisiae Ma is better,which can provide a good strain for the development of feed probiotics.
作者
张璐
周英昊
冯曼
宋连杰
刘爱瑜
董晴
苏东遥
李雪梅
高玉红
ZHANG Lu;ZHOU Yinghao;FENG Man;SONG Lianjie;LIU Aiyu;DONG Qing;SU Dongyao;LI Xuemei;GAO Yuhong(College of Animal Science and Technology,Hebei Agricultural University,Baoding 071000,China;Chengde Academy of Agriculture and Forestry,Chengde 067000,China)
出处
《动物营养学报》
北大核心
2025年第2期1354-1364,共11页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
河北省自然科学基金(C2023204024)
河北省重点研发计划项目(22326603D)
河北省羊产业体系(HBCT2024250403)。
关键词
育肥羊
酵母菌
益生特性
耐受性
抑菌能力
体外发酵
fattening sheep
yeast
probiotic characteristics
tolerance
bacteriostatic ability
in vitro fermentation
作者简介
张璐(1999-),女,河北秦皇岛人,硕士研究生,研究方向为动物营养与环境控制。E-mail:1751629854@qq.com;周英昊,同等贡献作者;通信作者:李雪梅,副教授,E-mail:meinyli@126.com;高玉红,教授,硕士生导师,E-mail:gyhsxs0209@126.com。
