An in vitro study of the probiotic potential of a bile-salt-hydrolyzing Lactobacillus fermentum strain,and determination of its cholesterol-lowering properties

This study evaluated the use of a bile-salt-hydrolyzing Lactobacillus fermentum strain as a probiotic with potential hypocholesterolemic properties. The effect of L. fermentum on representative microbial populations and overall metabolic activity of the human intestinal microbiota was investigated using a three-stage continuous culture system. Also, the use of galactooligosaccharides as a prebiotic to enhance growth and/or activity of the Lactobacillus strain was evaluated. Administration of L. fermentum resulted in a decrease in the overall bifidobacterial population (ca. 1 log unit). In the in vitro system, no significant changes were observed in the total bacterial, Lactobacillus, Bacteroides, and clostridial populations through L. fermentum supplementation. Acetate production decreased by 9 to 27%, while the propionate and butyrate concentrations increased considerably (50 to 90% and 52 to 157%, respectively). A general, although lesser, increase in the production of lactate was observed with the administration of the L. fermentum strain. Supplementation of the prebiotic to the culture medium did not cause statistically significant changes in either the numbers or the activity of the microbiota, although an increase in the butyrate production was seen (29 to 39%). Results from this in vitro study suggest that L. fermentum KC5b is a candidate probiotic which may affect cholesterol metabolism. The short-chain fatty acid concentrations, specifically the molar proportion of propionate and/or bile salt deconjugation, are probably the major mechanism involved in the purported cholesterol-lowering properties of this strain.     

Lactic acid bacteria isolated from canine faeces

AIMS: Lactic acid bacteria (LAB) were isolated and sequenced from the faeces of healthy dogs. Five of these strains were selected and further characterized to clarify the potential of these strains as probiotics for canine. METHODS AND RESULTS: LAB were found in 67% (14/21) of the canine faeces samples when plated on Lactobacilli Selective Media without acetic acid. Out of 13 species identified with partial 16S rRNA gene sequencing, Lactobacillus fermentum LAB8, L. mucosae LAB12, L. rhamnosus LAB11, L. salivarius LAB9 and Weissella confusa LAB10 were selected as candidate probiotic strains based on their frequency, quantity in faeces, growth density, acid tolerance and antimicrobial activity. The minimal inhibitory concentration values of these isolates were determined for 14 antibiotics. L. salivarius LAB9, W. confusa LAB10 and L. mucosae LAB12 were viable in pH 2 for 4 h (mLBS), indicating tolerance to acidity and thus the potential to survive in gastrointestinal tract of the canine. The LAB8-LAB12 strains showed antimicrobial activity against Micrococcus luteus A1 NCIMB86166. CONCLUSIONS: Thirteen different LAB species were found from the faecal microbiota of the healthy canines. Five acid tolerant and antimicrobially active LAB strains with the capacity to grow to high densities both aerobically and anaerobically were chosen to serve as candidate probiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: The selected LAB strains are among the first host-specific LAB with antimicrobial activity isolated from canines that could serve as potential probiotics for canine use.     

Safety assessment and enteric colonization ability of a native canine Lactobacillus murinus strain

The aim of this work was to assess the safety and survival in the canine gastrointestinal tract of a native Lactobacillus murinus strain using an in vivo approach. A spontaneous rifampicin-resistant strain generated from a native Lactobacillus murinus strain isolated from dog feces was used in an in vivo administration protocol performed in dogs. The parental strain had been previously characterized in our laboratory, showing interesting probiotic-related properties. The rifampicin-resistant mutant generally exhibited similar properties to the parental strain. When it was administered to healthy dogs, this strain was able to survive in the canine gut and diverse physiological parameters of the animals did not differ from those assessed in non-treated ones. The present in vivo study using a native canine Lactobacillus murinus strain allowed us to conclude that the assessed strain transiently persisted in the canine gut and is safe for administration in dogs. Results of this assay can contribute to the development of new strategies for health promotion in dogs. Future studies will be carried out to evaluate the potential probiotic strain in vivo in dogs under different clinical conditions.     

蒙古国地区酸乳中乳酸菌的鉴定及耐酸菌株筛选

本研究对采集自蒙古国地区牧民家庭中17份发酵乳样品中的乳杆菌进行了分离、鉴定、生物学特性和耐酸性研究。共分离出45株乳杆菌。通过形态观察、生理生化试验、糖发酵试验及16S rDNA序列分析等研究将这些菌株鉴定为Lactobacillum fermentum(L. fermentum)31 株, L. helveticus 12株, L. plantarum 1株 和L. casei 1株, 所以认为L. fermentum是蒙古国地区传统酸乳中的优势菌群。经pH 为3.0 的人工胃液耐受性试验复筛后发现, 存活率在80%以上的仅1株, IMAU20085的存活率高达81.44%。菌株的分离鉴定以及高耐酸性菌株的筛选, 对我国益生菌资源的保藏和开发有重要的意义, 对我国未来益生菌的开发具有重要价值。     

Different probiotic properties for Lactobacillus fermentum strains isolated from swine and poultry

Systematic procedures were used to evaluate the probiotic properties of Lactobacillus fermentum (L. fermentum) strains isolated from swine and poultry. The major properties included their capabilities to adhere to the intestinal epithelium of swine and poultry, the inhibition on pathogenic bacteria, and their tolerance to the gastric juice and bile salts. Results showed that L. fermentum strains from poultry digestive tract showed better adherence to the swine intestine and chicken crop epithelial cells as compared to those strains from the swine origin. In addition, six strains from poultry and one strain from swine showed adhesion specificity to their own intestinal epithelium. Four poultry isolates and one swine isolate were able to adhere to the epithelial cells from both swine and chicken. For gastric juice and bile tolerance, most of the strains isolated from swine or poultry were acid tolerant but less strains were bile intolerant. The spent culture supernatant (SCS) of these L. fermentum strains showed antagonistic effect against the indicator bacteria, such as Escherichia coli, Salmonella spp., Shigella sonnei and some enterotoxigenic Staphylococcus aureus. From the above studies, some L. fermentum strains isolated from poultry were found to have the probiotic properties required for use in animal feed supplement. This study suggested that poultry digestive tract may serve as potential source for the isolation of probiotic lactic acid bacteria.     

Evaluation of nitric oxide production by lactobacilli

Six strains of Lactobacillus fermentum and Lactobacillus plantarum were investigated for nitric oxide (NO) production. First, the potential presence of NO synthase was examined. None of the strains of L. fermentum and L. plantarum examined produced NO from L-arginine under aerobic conditions. Interestingly, all L. fermentum strains expressed strong L-arginine deiminase activity. All L. fermentum strains produced NO in MRS broth, but the NO was found to be chemically derived from nitrite, which was produced by L. fermentum from nitrate present in the medium. Indeed all L. fermentum strains express nitrate reductase under anaerobic conditions. Moreover, one strain, L. fermentum LF1, had nitrate reductase activity under aerobic conditions. It was also found that L. fermentum strains JCM1173 and LF1 possessed ammonifying nitrite reductase. The latter strain also had denitrifying nitrite reductase activity at neutral pH under both anaerobic and aerobic conditions. The LF1 strain is thus capable of biochemically converting nitrate to NO. NO and nitrite produced from nitrate by lactobacilli may constitute a potential antimicrobial mechanism. studied in a rat acute liver injury model (Adawi et al. 1997). The results indicate that Lactobacillus plantarum DSM 9842 may possess NOS (Adawi et al. 1997). However, NO production from L-arginine has not been investigated in pure cultures of L. plantarum. According to the results of a 15N enrichment experiment, traces of (NO2-+NO3-)-N (total oxidised nitrogen: TON), which seemed to be formed by the resting cells of Lactobacillus fermentum IFO3956, appeared to be derived from L-arginine (Morita et al. 1997). Therefore, it was suggested that L. fermentum may possess a NOS. However, NO produced from L-arginine was not directly measured and a NOS inhibitor test was not performed by Morita et al. (1997). It is known that L-arginine deiminase (ADI) in bacteria may convert L-arginine to NH4+ (Cunin et al. 1986), which may be further oxidised to TON via nitrification by bacteria. Therefore, 15N enrichment experiments could not definitely conclude that L. fermentum possess NOS to convert L-arginine directly to NO. In this study, six Lactobacillus strains belonging to L. plantarum and L. fermentum were measured for NO production in MRS broth. The metabolism of nitrate and L-arginine by the Lactobacillus cell suspensions was also studied. The possibility that NO and nitrite production by lactobacilli may be a potential probiotic trait is also discussed.     

Oral application ofEnterococcus faecium strain EE3 in healthy dogs

The ability of canine strain Enterococcus faecium EE3 to survive in healthy dogs and its effect on microbiological and biochemical parameters was determined. The strain was individually applied to 11 dogs per os at a dose of 10(9) CFU/mL (differed from 2 to 3 mL) for 1 week and persisted in feces for 3 months after cessation of its administration (reaching average concentration of 6.83 +/- 0.95 log CFU/g). Seven d after administration, a decrease in staphylococci and a significant decrease in Pseudomonas-like bacteria was observed. On the other hand, concentration of lactic acid bacteria increased but the growth of E. coli was not influenced. In the blood samples of dogs after 0-1 d (before application) and the blood samples 1 week after application, total lipids decreased in 8 dogs; the total protein also decreased. The levels of cholesterol were brought to the physiological level, i.e. in blood samples with low cholesterol values it increased to the physiological level and in those with high levels it decreased; cholesterol was not influenced in 3 dogs.     

Oral use of Lactobacillus rhamnosus GR-1 and L. fermentum RC-14 significantly alters vaginal flora: randomized,placebo-controlled trial in 64 healthy women

Urogenital infections afflict an estimated one billion people each year. The size of this problem and the increased prevalence of multi-drug resistant pathogens make it imperative that alternative remedies be found. A randomized, placebo-controlled trial of 64 healthy women given daily oral capsules of Lactobacillus rhamnosus GR-1 and Lactobacillus fermentum RC-14 for 60 days showed no adverse effects. Microscopy analysis showed restoration from asymptomatic bacterial vaginosis microflora to a normal lactobacilli colonized microflora in 37% women during lactobacilli treatment compared to 13% on placebo (P=0.02). Lactobacilli were detected in more women in the lactobacilli-treated group than in the placebo group at 28 day (P=0.08) and 60 day (P=0.05) test points. Culture findings confirmed a significant increase in vaginal lactobacilli at day 28 and 60, a significant depletion in yeast at day 28 and a significant reduction in coliforms at day 28, 60 and 90 for lactobacilli-treated subjects versus controls. The combination of probiotic L. rhamnosus GR-1 and L. fermentum RC-14 is not only safe for daily use in healthy women, but it can reduce colonization of the vagina by potential pathogenic bacteria and yeast.     

Lactobacilli and enterococci — Potential probiotics for dogs

Forty strains of enterococci and forty strains of lactobacilli isolated from feces of 10 healthy dogs were tested for the antimicrobial activity, tolerance to bile and adhesion activity. The total count of fecal enterococci reached 5.5 log CFU/g and of lactobacilli 7.6 log CFU/g. Screening for production of bacteriocin-like substances showed an to partly inhibit the growth of Enterobacter sp. (hazy zones of inhibition). Ten strains of Enterococcus sp. and nine strains of Lactobacillus sp. were found without any inhibitory activity against all indicators used. Seven enterococcal strains and six lactobacilli with the broadest antimicrobial spectrum were selected for further probiotic assays. In the presence of 1% bile, the survival rate of selected enterococci (71.7-97.5%) was higher than that of lactobacilli (66.7-75.4%). The adhesion of strains to human intestinal mucus (5.1-8.2% by enterococci, 2.7-8.3% by lactobacilli) was found to be similar as adhesion to canine intestinal mucus (3.7-10.6% by enterococci, 2.1-6.0% by lactobacilli). Strain AD1, one lactobacillus isolate, reduced the higher level of serum cholesterol and alanine aminotransferase after oral administration to dogs suffering from diseases of the gastrointestinal tract.     

Genetic diversity of the genus Lactobacillus bacteria from the human gastrointestinal microbiome

The species and strain genetic diversity of bacterial cultures belonging to the genus Lactobacillus, which were isolated from the gastrointestinal microbiome of the human population living in the former Soviet Union in the years 1960-1980, was studied. The bacteria demonstrated probiotic characteristics. Phylogenetic analysis of sequences of the gene coding for 16S rRNA detected earlier by us, showed that the gene found in bacteria isolated from the intestinal content of healthy adults and represented by species L. plantarum, L. helveticus, L. casei/paracasei, L. rhamnosus, and L. fermentum has high homology (97-100%) with this gene in type representatives of the species. The genotypic and strain diversity of cultures was studied using RAPD-PCR and nonspecific primers. This method with the use of the ERIC-1 primer gave reliable and reproducible results as compared that using with M13 and MSP primers and allowed the identification of examined bacteria belonging to the genus Lactobacillus at the level of species and certification at the strain level.     

The canine isolate Lactobacillus acidophilus LAB20 adheres to intestinal epithelium and attenuates LPS-induced IL-8 secretion of enterocytes in vitro

Background

For a good probiotic candidate, the abilities to adhere to intestinal epithelium and to fortify barrier function are considered to be crucial for colonization and functionality of the strain. The strain Lactobacillus acidophilus LAB20 was isolated from the jejunum of a healthy dog, where it was found to be the most pre-dominant lactobacilli. In this study, the adhesion ability of LAB20 to intestinal epithelial cell (IECs) lines, IECs isolated from canine intestinal biopsies, and to canine, porcine and human intestinal mucus was investigated. Further, we studied the ability of LAB20 to fortify the epithelial cell monolayer and to reduce LPS-induced interleukin (IL-8) release from enterocytes.

Results

We found that LAB20 presented higher adhesion to canine colonic mucus as compared to mucus isolated from porcine colon. LAB20 showed adhesion to HT-29 and Caco-2 cell lines, and importantly also to canine IECs isolated from canine intestinal biopsies. In addition, LAB20 increased the transepithelial electrical resistance (TER) of enterocyte monolayers and thus strengthened the intestinal barrier function. The strain showed also anti-inflammatory capacity in being able to attenuate the LPS-induced IL-8 production of HT-29 cells.

Conclusion

In conclusion, canine indigenous strain LAB20 is a potential probiotic candidate for dogs adhering to the host epithelium and showing intestinal barrier fortifying and anti-inflammatory effects.

Electronic supplementary material

The online version of this article (doi:10.1186/s12866-014-0337-9) contains supplementary material, which is available to authorized users.     

Cholesterol assimilation by lactic acid bacteria and bifidobacteria isolated from the human gut

The objective of this study was to evaluate the effect of human gut-derived lactic acid bacteria and bifidobacteria on cholesterol levels in vitro. Continuous cultures inoculated with fecal material from healthy human volunteers with media supplemented with cholesterol and bile acids were used to enrich for potential cholesterol assimilators among the indigenous bacterial populations. Seven potential probiotics were found: Lactobacillus fermentum strains F53 and KC5b, Bifidobacterium infantis ATCC 15697, Streptococcus bovis ATCC 43143, Enterococcus durans DSM 20633, Enterococcus gallinarum, and Enterococcus faecalis. A comparative evaluation regarding the in vitro cholesterol reduction abilities of these strains along with commercial probiotics was undertaken. The degree of acid and bile tolerance of strains was also evaluated. The human isolate L. fermentum KC5b was able to maintain viability for 2 h at pH 2 and to grow in a medium with 4,000 mg of bile acids per liter. This strain was also able to remove a maximum of 14.8 mg of cholesterol per g (dry weight) of cells from the culture medium and therefore was regarded as a candidate probiotic.     

Bioconversion of isoflavones and the probiotic properties of the electroporated parent and subsequent three subcultures of Lactobacillus fermentum BT 8219 in biotin-soymilk

This study was aimed at an evaluation of the potential inheritance of electroporation effects on Lactobacillus fermentum BT 8219 through to three subsequent subcultures, based on their growth, isoflavone bioconversion activities, and probiotic properties, in biotin-supplemented soymilk. Electroporation was seen to cause cell death immediately after treatment, followed by higher growth than the control during fermentation in biotin-soymilk (P<0.05). This was associated with enhanced intracellular and extracellular beta-glucosidase specific activity, leading to increased bioconversion of isoflavone glucosides to aglycones (P<0.05). The growing characteristics, enzyme, and isoflavone bioconversion activities of the first, second, and third subcultures of treated cells in biotin-soymilk were similar to the control (P>0.05). Electroporation affected the probiotic properties of parent L. fermentum BT 8219, by reducing its tolerance towards acid (pH 2) and bile, lowering its inhibitory activities against selected pathogens, and reducing its ability for adhesion, when compared with the control (P<0.05). The first, second, and third subcultures of the treated cells showed comparable traits with that of the control (P>0.05), with the exception of their bile tolerance ability, which was inherited to the treated cells of the first and second subcultures (P<0.05). Our results suggest that electroporation could be used to increase the bioactivity of biotin-soymilk via fermentation with probiotic L. fermentum BT 8219, with a view towards the development of functional foods.     

Complete glutathione system in probiotic Lactobacillus fermentum ME-3

There is much information about glutathione (GSH) in eukaryotic cells, but relatively little is known about GSH in prokaryotes. Without GSH and glutathione redox cycle lactic acid bacteria (LAB) cannot protect themselves against reactive oxygen species. Previously we have shown the presence of GSH in Lactobacillus fermentum ME-3 (DSM14241). Results of this study show that probiotic L. fermentum ME-3 contains both glutathione peroxidase and glutathione reductase. We also present that L. fermentum ME-3 can transport GSH from environment and synthesize GSH. This means that it is characterized by a complete glutathione system: synthesis, uptake and redox turnover ability that makes L. fermentum ME-3 a perfect protector against oxidative stress. To our best knowledge studies on existence of the complete glutathione system in probiotic LAB strains are still absent and glutathione synthesis in them has not been demonstrated.     

Effectivity of freeze-dried form of Lactobacillus fermentum AD1-CCM7421 in dogs

The impact of probiotic supplementation of canine-derived strain Lactobacillus fermentum AD1-CCM7421 in freeze-dried form on quantitative composition of microbiota and short-chain fatty acid profile in feces of dogs was demonstrated by two independent studies (straightforward repeated-measures model; study I: a dose of 2 g per dog for 2 weeks, 10⁸ CFU/g, n = 12; study II: 1 g per dog for 1 week, 10⁷ CFU/g, n = 11. The results revealed a significant increase of lactic acid bacteria population persisting also after the cessation of probiotic application in both studies. A reduction of clostridia (study I, p _sum < 0.01) and tested Gram-negative bacterial genera (coliforms, Aeromonas sp., Pseudomonas sp., study II, p < 0.05) was also detected. The strain AD1-CCM7421 colonized the canine digestive tract in sufficient numbers (10⁵–10⁶ CFU/g) and it persisted in the majority of dogs after cessation of probiotic application. An increase of short-chain fatty acid concentrations (study I: butyric, succinic, valeric, formic acid) especially in the early post-treatment phase (p < 0.05) most likely led to a decrease of fecal pH value (p < 0.05) without negative influence on fecal consistency throughout the studies.     

Predominant genera of fecal microbiota in children with atopic dermatitis are not altered by intake of probiotic bacteria Lactobacillus acidophilus NCFM and Bifidobacterium animalis subsp. lactis Bi-07

The effect of probiotic bacteria Lactobacillus acidophilus NCFM and Bifidobacterium lactis Bi-07 on the composition of the Lactobacillus group, Bifidobacterium and the total bacterial population in feces from young children with atopic dermatitis was investigated. The study included 50 children randomized to intake of one of the probiotic strain or placebo. Microbial composition was characterized by denaturing gradient gel electrophoresis, quantitative PCR and, in a subset of subjects, by pyrosequencing of the 16S rRNA gene. The core population of the Lactobacillus group was identified as Lactobacillus gasseri, Lactobacillus fermentum, Lactobacillus oris, Leuconostoc mesenteroides, while the bifidobacterial community included Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium longum and Bifidobacterium catenulatum. The fecal numbers of L. acidophilus and B. lactis increased significantly after intervention, indicating survival of the ingested bacteria. The levels of Bifidobacterium correlated positively (P=0.03), while the levels of the Lactobacillus group negatively (P=0.01) with improvement of atopic eczema evaluated by the Severity Scoring of Atopic Dermatitis index. This correlation was observed across the whole study cohort and not attributed to the probiotic intake. The main conclusion of the study is that administration of L. acidophilus NCFM and B. lactis Bi-07 does not affect the composition and diversity of the main bacterial populations in feces.     

Experimental addition of <Emphasis Type="Italic">Eleutherococcus senticosus</Emphasis> and probiotic to the canine diet

There is a current trend to support pet health through the addition of natural supplements to their diet, taking into account the high incidence of medical conditions related to their immune system and gastrointestinal tract. This study investigates effects of the plant Eleutherococcus senticosus as a dietary additive on faecal microbiota, faecal characteristics, blood serum biochemistry and selected parameters of cellular immunity in healthy dogs. A combination of the plant with the canine-derived probiotic strain Lactobacillus fermentum CCM 7421 was also evaluated. Thirty-two dogs were devided into 4 treatment groups; receiving no additive (control), dry root extract of E. senticosus (8 mg/kg of body weight), probiotic strain (10⁸ CFU/mL, 0.1 mL/kg bw) and the combination of both additives. The trial lasted 49 days with 14 days supplementation period. Results confirm no antimicrobial effect of the plant on the probiotic abundance either in vitro (cultivation test) or in vivo. The numbers of clostridia, lactic acid bacteria and Gram-negative bacteria as well as the concentration of serum total protein, triglyceride, glucose and aspartate aminotransferase were significantly altered according to the treatment group. Leukocyte phagocytosis was significantly stimulated by the addition of probiotic while application of plant alone led to a significant decrease.     

Intestinal dysbacteriosis in antibacterial therapy and perspectives in treatment by antibiotic-resistant probiotics]

Effect of different antibiotics and standard antibacterial therapy regimes on intestine microflora was investigated. Lincozamides demonstrated the most negative effect. Early addition of probiotics to the treatment with antibacterials had positive effect. Susceptibility of 21 strains of normal microflora to 25 antibiotics was tested. Resistance to antibiotics of lactobacilli varied significantly (more among strains and less among species). It was shown that L. acidophilus (probiotic "Acilact") was resistant to metronidazole only. High resistance to antibiotics was shown for L. plantarum 8RA3, L. fermentum 90T4C (components of probiotic "Lactobacterin"), L. fermentum BL96, L. acidophilus BL and L. acidophilus (component of "Linex"). Susceptibility of microorganisms in complex formulation "Linex" to the modern antibiotics was low. It is concluded that the use of stable antibiotic-resistant strains of normal microflora is favorable as addition to antibiotic therapy.     

Alteration of the Canine Small-Intestinal Lactic Acid Bacterium Microbiota by Feeding of Potential Probiotics

Five potentially probiotic canine fecal lactic acid bacterium (LAB) strains, Lactobacillus fermentum LAB8, Lactobacillus salivarius LAB9, Weissella confusa LAB10, Lactobacillus rhamnosus LAB11, and Lactobacillus mucosae LAB12, were fed to five permanently fistulated beagles for 7 days. The survival of the strains and their potential effects on the indigenous intestinal LAB microbiota were monitored for 17 days. Denaturing gradient gel electrophoresis (DGGE) demonstrated that the five fed LAB strains survived in the upper gastrointestinal tract and modified the dominant preexisting indigenous jejunal LAB microbiota of the dogs. When the LAB supplementation was ceased, DGGE analysis of jejunal chyme showed that all the fed LAB strains were undetectable after 7 days. However, the diversity of the intestinal indigenous microbiota of the dogs, as characterized from jejunal chyme plated on Lactobacillus selective medium without acetic acid, was reduced and did not return to the original level during the study period. In all but one dog, an indigenous Lactobacillus acidophilus strain emerged as the dominant LAB strain. In conclusion, strains LAB8 to LAB12 have potential as probiotic strains for dogs as they survive in and dominate the jejunal LAB microbiota during feeding and have the ability to modify the intestinal microbiota.     

Viable Intestinal Passage of a Canine Jejunal Commensal Strain Lactobacillus acidophilus LAB20 in Dogs

The strain Lactobacillus acidophilus LAB20 with immunomodulatory properties was previously found dominant in the jejunal chyme of four dogs, and the novel surface layer protein of LAB20 suggested its competitive colonization in canine gut. To evaluate the persistence and survival of LAB20 in healthy dogs, LAB20 was fed to five healthy pet dogs for 3 days, at a dosage of 10⁸ CFU daily as fermented milk supplement. The fecal samples, from 1 day prior to feeding, three continuous feeding days, and on day 5, 7, 14, and 21, were collected for strain-specific detection of LAB20 using real-time PCR. We found that LAB20 count was significantly increased in dog fecal samples at the second feeding day, but rapidly decreased after feeding ceased. The fecal samples from prior to feeding, during feeding, and post-cessation days were plated onto mLBS7 agar, from where LAB20 was recovered and distinguishable from other fecal lactobacilli based on its colony morphotype. Using strain-specific PCR detection, the colonies were further verified as LAB20 indicating that LAB20 can survive through the passage of the canine intestine. This study suggested that canine-derived strain LAB20 maintained at high numbers during feeding, viably transited through the dog gut, and could be identified based on its colony morphotype.