Isolation,identification,and probiotic characteristics evaluation of Lactobacillus from the reproductive tract of dairy cows in Dali Prefecture Area
Wang Tao
Ma Ke
Zhang Jiangang
Cao Rongchang
Zhou Qun
Xie Xiaodong
Abstract：The experiment aims to explore the probiotic properties and safety of Lactobacillus in the reproductive tracts of postpartum healthy dairy cows.The uterine secretions of healthy dairy cows 26 days postpartum were collected aseptically.Lactobacillus were isolated using MRS Medium.The types of isolates were identified by Gram staining,biochemical characteristic identification and 16S rRNA sequence.The probiotic properties and safety of the isolates were evaluated through tests such as acid production capacity,antibacterial ability,antibiotic sensitivity,hemolysis characteristics and adhesion.The results showed that the isolated strain Y70 was Limosilactobacillus pontis,which had a fast growth rate and a short cycle.The pH value of the bacterial liquid eventually stabilized at around 3.6,indicating a strong acid production capacity.The cell-free supernatant of the strain can inhibit the proliferation of five common pathogenic bacteria,namely Klebsiella pneumoniae,Pseudomonas aeruginosa,Escherichia coli,Listeria and Salmonella pullorum disease,among which the inhibitory effect on Pseudomonas aeruginosa is the strongest.The isolated strain Y70 was sensitive or moderately sensitive to 11 common antibiotics such as ampicillin and erythromycin,but showed certain resistance to eight antibiotics such as tetracycline and oxacillin.The strain did not exhibit hemolysis but showed γ-hemolysis.When the infection multiplicity(MOI)=100,the adhesion to Caco-2 cells can reach 40％(40 CFU/cell),indicating strong adhesion.Studies have shown that Limosilactobacillus pontis Y70 has excellent probiotic properties and can be used as a candidate strain for the development of microecological preparations for bovine endometritis.
Keywords：Dairy cowsEndometritisLactobacillusProbiotic propertiesMicroecological preparations
Publication Date：2025-10-15
Online Publishing Date：2025-11-24(First online date of this platform, not the publication date of the document)
Pages：7( 1-7 )