30周龄笼养海蓝褐壳蛋鸡盲肠中优良乳酸菌的筛选

Screening and identification of Lactic acid bacteria in 30 week old caged Hyline brown laying hens

目的对笼养蛋鸡盲肠中的优良乳酸菌进行筛选与鉴定。方法以30周龄笼养海蓝褐壳蛋鸡盲肠分离纯化得到10株乳酸菌为试验菌,通过发酵产酸力、耐酸性和耐胆盐的筛选试验,获得产酸能力高、对酸和胆盐有高耐受力的乳酸菌,进行生长曲线和产酸曲线及对抗生素的耐受力的测定,并采用API CHL50试剂条对选出的乳酸菌进行鉴定。结果 10株乳酸菌在发酵起始时间点时p H在6.10~6.40,经过48 h的发酵阶段,发酵液的p H明显降低;酸性环境和胆盐对各菌株存活率均有抑制。CL1、CL12和CL54生长较快,最佳生长和产酸发酵时间是24 h,CL26和CL31生长相对较慢,到32 h时生长曲线达到最高点;对抗生素的耐受力检测结果显示,CL1、CL12和CL54对抗生素的耐受力很高,而CL26和CL31对抗生素的耐受力较弱。结论对CL1、CL12和CL54这三株菌进行种属鉴定。根据API CHL50生化鉴定条说明进行接菌发酵试验,经对照鉴定,CL1为Lactococcus Lactis ssp Lactis1（乳酸乳球菌亚种1）,CL12为Pediococcus Acidilactici（乳酸片球菌）,CL54为Lactobacillus Brevis1（短乳杆菌1）。

Objective This experiment mainly carries on screening and identification of lactic acid bacteria in the caecum of layers. Methods 10 lactic acid bacteria isolated from cecum contents of laying hens fed in cages were determined on ability of acid production,acid resistance and bile salt resistance,to obtain the high quality LAB to determine their growth curves,acid production and ability of anti-drugs,and API CHL50 were conducted to identify the bacteria family. Results All p H of 10 strains decreased significantly from the initial p H 6. 1- 6. 4 after fermentation for 48 h. With the culture p H decreased or the culture bile salt concentration increased and treated time delayed,the survival rate of every strain decreased. CL1,CL12 and CL54 grown faster and the best fermentation time was 24 h,while CL26 and CL31 grown slower a little and the best fermentation time was 32 h. CL1,CL12 and CL54 had higher ability to anti-drugs,while CL26 and CL31 had lower activity to anti-drugs. Conclusion CL1,CL12 and CL54 were selected and identified by API CHL50,results show that CL1 is Lactococcus Lactis ssp Lactis1,CL12 is Pediococcus Acidilactici,and CL54 is Lactobacillus Brevis1.