Effect of the two-year milk-feeding on the gastrointestinal microflora of the cynomolgus monkey (Macaca fascicularis)

The effect of the two-year milk-feeding on the gastrointestinal (GI) microflora of a cynomolgus monkey was determined. Bifidobacterium spp. in the animal fed with cow's milk alone were distributed in higher number in the stomach, duodenum, cecum, and rectum. The increasingly higher numbers of Lactobacillus spp. and Candida spp. were counted in all regions of the GI tract of the animal fed with the formula diet. Bacteroidaceae, Enterobacteriaceae, and Streptococcus spp. were detected from the upper to lower intestines in the monkey given only milk, whereas in the monkey given the formula, those bacterial species were localized in only the lower intestines.     

A mixture of organisms affects cholesterol metabolism together with rat cecal flora.

The effects of a mixture of organisms on cecal fermentation and cholesterol metabolism in sham-operated and cecectomized rats were investigated. Male F344 rats, allocated into four groups: cecectomized rats fed a mixture of organisms (CEMO), cecectomized rats fed rice bran (CERB), sham-operated rats fed a mixture of organisms (SHMO), and sham-operated rats fed rice bran (SHRB) for 4 weeks. The diets had 0.5% cholesterol and 0.125% sodium cholate added. There were no significant differences in the body weight gain and food intake among the groups. The cecal pH in the SHMO group was significantly lower than that in the other groups. The total cholesterol and (VLDL + IDL + LDL)-cholesterol concentrations in serum were significantly lower in the SHMO group than that in the SHRB group, and the triacylglycerol concentration in the sham-operated rats tended to decrease compared to the cecectomized rats. The fecal cholesterol excretion in the CERB group was higher than that in the other groups, and that in the SHMO group was significantly higher than in the SHRB group. The acetic acid, propionic acid, n-butyric acid, and total short-chain fatty acid concentrations in the cecum contents were significantly higher in the SHMO group than those in the other groups. Streptococcus, Bifidobacterium, and Lactobacillus in the SHMO group tended to be higher than the other groups and Bacteroidaceae in the CEMO and CERB groups were significantly higher than that in the SHMO group. The results demonstrate that the mixture of organisms was fermented with the cecal contents and that the metabolites such as short-chain fatty acid lowered the serum total cholesterol and liver cholesterol concentrations in the rats fed a cholesterol-containing diet.     

Cellulolytic and non-cellulolytic bacteria in rat gastrointestinal tracts.

Lactobacillus and Bifidobacterium species were the predominant organisms isolated from small intestinal (jejunal) contents of rats, and lactic acid was the only organic acid detected. The numbers of cellulolytic bacteria in small intestines were low (approximately 10(3)/g). The fermentation in ceca was different from that in intestines, as, in addition to small amounts of lactic acid, high concentrations of volatile fatty acids were detected. The mixed cecal microflora was able to digest cellulose (pebble-milled Whatman no. 1) and cabbage. High numbers of cellulolytic bacteria were found (0.5 X 10(8) to 12.2 X 10(8)/g; 6% of total viable bacteria). The predominant celluloytic organism isolated was Bacteroides succinogenes. Ruminococcus flavifaciens was isolated from a few animals. The kinds and numbers of the predominant non-cellulolytic organisms isolated from rat ceca were similar to those described by previous workers.     

Impact of colostomy on intestinal microflora and bacterial translocation in young rats fed with heat-killed Lactobacillus acidophilus strain LB

A rat animal model of left colostomy was found to significantly impair the growth curve of rats. Assessment of the intestinal flora showed that colostomy mostly affects the cecal but not colonic microflora. Generally, the number of enterococci was increased in both ileum and cecum; cecal lactobacilli also rose, accounting for a promotion of lactic acid bacteria in colostomised rats. No significant differences between colostomised, laparotomised and control rats could be observed for the translocation of intestinal bacteria to internal organs of rats (i.e. spleen, kidneys, lungs or liver), whatever their diet. Heat-killed Lactobacillus acidophilus strain LB administration (dead probiotic bacteria) tended to exhibit a stimulatory effect on bifidobacteria, probably affecting the culture-medium fermentation substances included in the pharmaceutical product. This effect was abolished by laparotomy and colostomy. A trend towards a probiotic-like effect, not susceptible to colostomy, was also witnessed as counts of lactobacilli tended to increase in both cecum and colon of all animals fed with L. acidophilus LB.     

Establishment of specific pathogen-free (SPF) rat colonies using gnotobiotic techniques.

Gnotobiotic Wistar rats were produced using gnotobiotic techniques, which were established in the production of a SPF mouse colony, in order to establish a barrier-sustained colony. One strain of Escherichia coli, 28 strains of Bacteriodaceae (B-strains), three strains of Lactobacillus (L-strains) and a chloroform-treated fecal suspension (CHF, Clostridium mixture) were prepared from conventional Wistar rats as the microflora source. Two groups of limited-flora rats, E. coli plus B-strains and E. coli plus CHF, were produced. After confirmation that Clostridium difficile was not detected in the CHF-inoculated rats, two groups of limited-flora rats were transferred to an isolator and housed together in a cage. These rats were then orally inoculated with L-strains. The gnotobiotic rats showed colonization resistance to Pseudomonas aeruginosa, and the number of E. coli in the feces was 10(5) to 10(6)/g. The gnotobiotic rats were transferred to a barrier room as a source of intestinal flora for SPF colonies. In the SPF rats, basic cecal flora was mainly composed of Bacteroidaceae, clostridia, fusiform-shaped bacteria and lactobacilli, and did not change over a long period. Their flora became similar to that of conventional rats.     

产酶益生素对肉鸭生长性能及肠道菌群的影响

目的产酶益生素对肉鸭生产性能及肠道菌群的影响,为开发利用产酶益生素提供理论依据。方法选用1日龄120只樱桃谷肉鸭,随机分为4组,每组30只,设2个重复,每重复15只,对照组I饲喂基础日粮,实验II、III和IV组分别在基础日粮中添加0.1%、0.2%和0.3%产酶益生素,测定肉鸭的生长性能及肠道菌群数量。结果与对照组相比,实验II、III和IV组平均日增重分别提高了5.82%、11.50%和12.60%,日均采食量分别提高了0.85%、1.71%和3.78%,料重比分别降低了4.85%、8.81%和7.93%;盲肠内双歧杆菌的数量分别提高了3.29%、9.86%和9.48%,乳酸杆菌分别提高了5.49%、10.98%和12.56%,大肠埃希菌分别降低了11.88%、16.35%和22.48%。结论产酶益生素能提高肉鸭的生产性能,促进肠道双歧杆菌及乳酸杆菌的增殖,降低大肠埃希菌的数量。     

Effects of age and starvation on the gastrointestinal microflora and the heat resistance of fecal bacteria in rats.

The microflora of the gastrointestinal tract in rats 1 day to 100 weeks old, of the cecal contents and wall in starved rats, and of heat-treated feces of normal rats was determined by cultural examination. Streptococci, staphylococci, lactobacilli, actinobacilli, and coliforms colonized the tract during the 1st week of life. Bacteroidaceae, veillonellae, catenabacteria (composed of eubacteria and anaerobic lactobacilli), clostridia, bifidobacteria, anaerobic gram-positive cocci, fusiform bacteria, curved rods, and spirochetes appeared when the rats were 2 to 4 weeks old. Yeasts were slower in colonizing the tract than any other organism. Dramatic changes occurred in the microflora of rats 2 to 4 weeks of age. There was a time lag between the changes in enterococcal and coliform populations. The enterococcal population was depressed over a period from 2 to 6 weeks of age. Bifidobacteria showed a larger population at 4 to 9 weeks than at any other age. The microflora of the stomach was the same as that of the small intestine, with some exceptions. It differed markedly from that of the cecum. The ratio of total aerobic count to anaerobic count gradually increased in the stomach, but decreased in the cecum, with advance in age. The microorganisms distributed in the tract could be divided roughly into 3 types. The population of each organism, except spirochetes, in the cecal wall was approximately 1/1,000 of that in the cecal contents. One of the 2 types of spirochetes was found only in the cecal wall and in a high incidence, forming a large population. In rats starved for 48 hr, coliforms, Proteus spp., anaerobic gram-positive cocci, Clostridia, and some bacteroidaceae showed an increase in population in the cecum, but lactobacilli, veillonellae, and spirochetes decreased. The major organisms cultured from the heat-treated feces were fusiform and curved bacteria, some members of Bacillus, minor anaerobic cocci, and straight rods.     

Effect on components of the intestinal microflora and plasma neuropeptide levels of feeding Lactobacillus delbrueckii, Bifidobacterium lactis, and inulin to adult and elderly rats

The aim of this study was to compare the effects of the mixture of Lactobacillus delbrueckii subsp. rhamnosus strain GG, Bifidobacterium lactis Bb12, and inulin on intestinal populations of lactobacilli, bifidobacteria, and enterobacteria in adult and elderly rats fed the same (in quality and quantity) diet. The portal plasma levels of two neuropeptides, neuropeptide Y (NPY) and peptide YY (PYY), were also evaluated to assess the physiological consequences of the synbiotic treatment for the gastrointestinal (GI) tracts of rats of different ages. Adult (n = 24) and elderly (n = 24) male rats were fed the AIN-93 M maintenance diet. After 2 weeks of adaptation, the diet of 12 rats of each age group was supplemented with 8% inulin and with strains GG and Bb12 to provide 2.2 x 10(9) CFU of each strain g(-1) of the diet. Blood and different regions of the GI tract were sampled from all rats after 21 days of the treatment. Treatment with the mixture of strain GG, strain BB12, and inulin induced significantly different changes in the numbers of lactobacilli, bifidobacteria, and enterobacteria of the stomach, small intestine, cecum, and colon microflora. Moreover, the GG, BB12, and inulin mixture increased the concentrations of NPY and PYY for adult rats. For the elderly animals, the PYY concentration was not changed, while the NPY concentration was decreased by treatment with the GG, BB12, and inulin mixture. The results of the present study indicate that the physiological status of the GI tract, and not just diet, has a major role in the regulation of important groups of the GI bacteria community, since even the outcome of the dietary modification with synbiotics depends on the ages of the animals.     

Modulation of rat cecal microbiota by administration of raffinose and encapsulated Bifidobacterium breve

To investigate the effects of administration of raffinose and encapsulated Bifidobacterium breve JCM 1192T cells on the rat cecal microbiota, in a preclinical synbiotic study groups of male WKAH/Hkm Slc rats were fed for 3 weeks with four different test diets: basal diet (group BD), basal diet supplemented with raffinose (group RAF), basal diet supplemented with encapsulated B. breve (group CB), and basal diet supplemented with both raffinose and encapsulated B. breve (group RCB). The bacterial populations in cecal samples were determined by fluorescence in situ hybridization (FISH) and terminal restriction fragment length polymorphism (T-RFLP). B. breve cells were detected only in the RCB group and accounted for about 6.3% of the total cells as determined by FISH analysis. B. breve was also detected only in the RCB group by T-RFLP analysis. This was in contrast to the CB group, in which no B. breve signals were detected by either FISH or T-RFLP. Increases in the sizes of the populations of Bifidobacterium animalis, a Bifidobacterium indigenous to the rat, were observed in the RAF and RCB groups. Principal-component analysis of T-RFLP results revealed significant alterations in the bacterial populations of rats in the RAF and RCB groups; the population in the CB group was similar to that in the control group (group BD). To the best of our knowledge, these results provide the first clear picture of the changes in the rat cecal microbiota in response to synbiotic administration.     

Profiling of composition and metabolic activities of the colonic microflora of growing pigs fed diets supplemented with prebiotic oligosaccharides

It is evident that quantitative information on different microbial groups and their contribution in terms of activity in the gastrointestinal (GI) tract of humans and animals is required in order to formulate functional diets targeting improved gut function and host health. In this work, quantitative information on levels and spatial distributions of Bacteroides spp, Eubacterium spp, Clostridium spp, Escherichia coli, Bifidobacterium spp and Lactobacillus/Enterococcus spp. along the porcine large intestine was investigated using 16S rRNA targeted probes and fluorescent in situ hybridisation (FISH). Caecum, ascending colon (AC) and rectum luminal digesta from three groups of individually housed growing pigs fed either a corn-soybean basal diet (CON diet) or a prebiotic diet containing 10 g/kg oligofructose (FOS diet) or trans-galactooligosaccharides (TOS diet) at the expense of cornstarch were analysed. DAPI staining was used to enumerate total number of cells in the samples. Populations of total cells, Bacteroides, Eubacterium, Clostridium and Bifidobacterium declined significantly (P < 0.05) from caecum to rectum, and were not affected by dietary treatments. Populations of Lactobacillus/Enterococcus and E. coli did not differ throughout the large intestine. The relative percent (%) contribution of each bacterial group to the total cell count did not differ between caecum and rectum, with the exception of Eubacterium that was higher in the AC digesta. FISH analysis showed that the sum of all bacterial groups made up a small percentage of the total cells, which was 12.4%, 21.8% and 10.3% in caecum, AC and rectum, respectively. This supports the view that in swine, the diversity of GI microflora might be higher compared to other species. In terms of microflora metabolic activity, the substantially higher numerical trends seen in FOS and TOS treatments regarding total volatile fatty acid, acetate concentrations and glycolytic activities, it could be postulated that FOS and TOS promoted saccharolytic activities in the porcine colon.     

饲喂乳杆菌对雏鸡盲肠8种正常菌群定植的影响

本文以鸡乳杆菌培养物饲喂新生雏鸡来观察其对雏鸡盲肠８种正常菌群定植的影响。结果表明：雏鸡饲喂乳杆菌培养物后,１０日龄前,盲肠内大肠杆菌数明显降低（Ｐ＜００１）,双歧杆菌、类杆菌和乳杆菌数明显增多（Ｐ＜００１）。其它菌群未发生变化     

断奶仔猪肠道菌群的研究

研究断奶仔猪在不同生理状况下的肠道菌群,结果表明：健康仔猪肠道内容物中,从十二指肠到结肠,所测定的８种细胞数量都随肠段后移而逐渐增加,４３日龄仔猪肠道内容物中以乳杆菌、肠球菌和梭菌占绝对优势,双歧杆菌次之;与健康仔猪相比,下痢仔猪肠道中肠球菌、梭菌和乳杆菌等优势菌群的数量明显低于对照组;饲喂了含肠球菌的活菌制剂的仔猪肠道中双歧杆菌和类杆菌的数量比对照组明显增加,但肠球菌数量却无显著改变。     

The effects of transgalactosylated oligosaccharides on gut flora metabolism in rats associated with a human faecal microflora

The effect on various caecal bacteria and their metabolic activities of feeding diet containing transgalactosylated oligosaccharides (TOS) with or without Bifidobacterium breve (administered in the drinking water) was investigated in rats colonized with a human faecal microflora. TOS (5% w/w in diet) or TOS plus B. breve, given for 4 weeks, induced increases in caecal concentration of total anaerobic bacteria, lactobacilli and bifidobacteria, and decreases in numbers of enterobacteria. Caecal pH was significantly reduced by feeding TOS, as were the activities of β-glucuronidase and nitrate reductase. In contrast, β-glucosidase activity was increased in TOS-fed rats.
Dietary TOS was also associated with decreased conversion, by caecal contents, of the dietary carcinogen 2-amino-3-methyl-3H-imidazo[4, 5- f ] quinoline (IQ) to its genotoxic 7-hydroxy derivative.     

Changes in fecal microflora induced by intubation of mice with Bacillus subtilis (natto) spores are dependent upon dietary components.

We examined changes in mouse fecal microflora after various dietary components and Bacillus subtilis (natto) spores were delivered by intubation. The administration of intact spores of Bacillus subtilis (natto) did not affect fecal Enterobacteriaceae and Enterococcus spp. in all three diet groups; on the other hand, it did affect fecal Bacteroidaceae and Lactobacillus spp., depending upon the diets fed. The administration of autoclaved spores did not alter fecal microflora. In vitro cultures of Lactobacillus murinus obtained from mouse feces, together with Bacillus subtilis (natto) under aerobic conditions as a mixed culture, revealed that the growth of L. murinus was enhanced by the addition of intact spores of Bacillus subtilis (natto). This enhancement of growth was displayed only in media containing either sucrose, glucose, maltose, or fructose but not in media containing cornstarch, soluble starch, or microcrystalline cellulose. From these results it was evident that some metabolites of Bacillus subtilis (natto) produced during germination and (or) outgrowth of spores of this strain, requiring monosaccharides or oligosaccharides, participated in the enhancement of the growth of L. murinus.     

Effects of dietary antibiotics on intestinal microflora in broiler chickens

Changes were examined in the intestinal microflora in broiler chickens fed a diet containing antibiotics to obtain fundamental information on the mechanisms of beneficial effect of the antibiotics upon livestock production. Three antibiotics (colistin, bacitracin, and enramycin) were employed as feed additives. Experiments were conducted with broiler chickens in two ways. In one way dietary antibiotics were fed continually at levels approved for use as feed additives for a long term. In the other they were fed the same antibiotics for a short term. Significant changes in microflora were observed mainly in such bacterial groups as aerobic bacteria and Lactobacillus. In the long term administration, three possible modes of variance in the bacterial flora were postulated: Changes directly related to the antibacterial spectrum of antibiotics. Antagonistic changes related to an ecological balance in the bacterial flora. Changes in quantitative balance of bacteria constituting each bacterial group. The change in the intestinal microflora during administration of the antibiotic diet was expressed as a complex form of these transition modes. In the short term administration, it was demonstrated that the effect of the antibiotic diet lingered even 7 days after administration. This suggests that antibiotics used as feed additives may possibly affect the stability of the intestinal microflora.     

Fecal microflora of Greek healthy neonates

This study aimed to explore, in our geographical region, the development of intestinal microflora and the colonization patterns of lactic acid bacteria and bifidobacteria during the first three months of life and to investigate the effect of the mode of delivery. Fecal specimens from 82 healthy, full-term infants were collected prospectively 4, 30 and 90 days after delivery and subcultured on nonselective and selective media. Identification of isolates was performed by microbiological and molecular methods. For the delivery effect, two groups of vaginally or caesarean-delivered exclusively breast-fed infants were studied. Despite the early high total counts of aerobes and anaerobes, colonization of lactobacilli and bifidobacteria was overall limited until 3 months of age. Furthermore, caesarean-delivered infants were less often colonized with lactobacilli at day 4 (4% vs. 59%, p = 0.000) and with bifidobacteria at day 4 (0% vs. 23%, p = 0.015) and 30 (0% vs. 35%, p = 0.042) compared to vaginally delivered ones. No bacterial populations differences were detected to compare colonized infants. Identification results indicated the predominance of Lactobacillus rhamnosus, Lactobacillus johnsonii and Lactobacillus paracasei species in neonatal gut microflora up to the first month of life and diversity of Lactobacillus species in vaginally delivered, colonized newborns, at fourth day. Furthermore, Bifidobacterium longum and Bifidobacterium breve were the most frequently detected Bifidobacterium species in vaginally delivered, breast-fed infants. In conclusion our study revealed a restricted colonization pattern of lactic acid bacteria in Greek infants and a delay in the development of Lactobacillus and Bifidobacterium spp. microbiota after caesarean section. Further analysis of potential consequences of these findings is required.     

16S rRNA-based analysis of microbiota from the cecum of broiler chickens.

The microbiota of the intestinal tract of chickens plays an important role in inhibiting the establishment of intestinal pathogens. Earlier culturing and microscopic examinations indicated that only a fraction of the bacteria in the cecum of chickens could be grown in the laboratory. Therefore, a survey of cecal bacteria was done by retrieval of 16S rRNA gene sequences from DNA isolated from the cecal content and the cecal mucosa. The ribosomal gene sequences were amplified with universal primers and cloned or subjected to temporal temperature gradient gel electrophoresis (TTGE). Partial 16S rRNA gene sequences were determined from the clones and from the major bands in TTGE gels. A total of 1,656 partial 16S rRNA gene sequences were obtained and compared to sequences in the GenBank. The comparison indicated that 243 different sequences were present in the samples. Overall, sequences representing 50 phylogenetic groups or subgroups of bacteria were found, but approximately 89% of the sequences represented just four phylogenetic groups (Clostridium leptum, Sporomusa sp., Clostridium coccoides, and enterics). Sequences of members of the Bacteroides group, the Bifidobacterium infantis subgroup, and of Pseudomonas sp. each accounted for less than 2% of the total. Sequences related to those from the Escherichia sp. subgroup and from Lactobacillus, Pseudomonas, and Bifidobacterium spp. were generally between 98 and 100% identical to sequences already deposited in the GenBank. Sequences most closely related to those of the other bacteria were generally 97% or less identical to those in the databases and therefore might be from currently unknown species. TTGE and random cloning indicated that certain phylogenetic subgroups were common to all birds analyzed, but sequence data from random cloning also provided evidence for qualitative and quantitative differences among the cecal microbiota of individual birds reared under very similar conditions.     

Effects of an abrupt diet change from hay to concentrate on microbial numbers and physical environment in the cecum of the pony

Microbial numbers, pH, fluid volume, and turnover rate in the pony cecum were measured during an abrupt change from an all-forage to an all-concentrate diet, both fed at maintenance energy levels. Concentrate feeding resulted in increased (P less than 0.01) numbers of total viable anaerobic bacteria. The numbers of organisms growing on selective starch medium increased (P less than 0.01) when concentrate was fed, while numbers on xylan and pectin media decreased (P less than 0.025). Seven days after the diet change to concentrate, the number of bacteria growing on lactate medium increased (P less than 0.01), followed by a gradual decline. Cellulolytic bacteria occurred in low numbers, ranging from 1.1 x 10(4) to 4.4 x 10(4) per g of cecal contents. Feeding all concentrate decreased both the number of genera (P less than 0.01) and total protozoan numbers (P less than 0.01) in the cecum. Minimum cecal pH values of 6.4 and 5.8 were obtained when forage and concentrate, respectively, were fed, with the minimum pH occurring 6 h postfeeding. Dry-matter percentage of cecal contents followed a diurnal pattern which was the inverse of the pH curve. During forage feeding, the cecum contained an average of 2.2 liters (1.6 to 3.4 liters), which turned over 3.9 times per day. When concentrate was fed, cecal volume averaged 3.9 liters (0.6 to 8.6 liters), with a mean liquid turnover of 4.2 times per day. Microbial numbers and pH changes in the pony cecum associated with an abrupt change in diet from hay to concentrate resembled those which occur in the rumen under similar feeding conditions.     

Effects of an abrupt diet change from hay to concentrate on microbial numbers and physical environment in the cecum of the pony.

Microbial numbers, pH, fluid volume, and turnover rate in the pony cecum were measured during an abrupt change from an all-forage to an all-concentrate diet, both fed at maintenance energy levels. Concentrate feeding resulted in increased (P less than 0.01) numbers of total viable anaerobic bacteria. The numbers of organisms growing on selective starch medium increased (P less than 0.01) when concentrate was fed, while numbers on xylan and pectin media decreased (P less than 0.025). Seven days after the diet change to concentrate, the number of bacteria growing on lactate medium increased (P less than 0.01), followed by a gradual decline. Cellulolytic bacteria occurred in low numbers, ranging from 1.1 x 10(4) to 4.4 x 10(4) per g of cecal contents. Feeding all concentrate decreased both the number of genera (P less than 0.01) and total protozoan numbers (P less than 0.01) in the cecum. Minimum cecal pH values of 6.4 and 5.8 were obtained when forage and concentrate, respectively, were fed, with the minimum pH occurring 6 h postfeeding. Dry-matter percentage of cecal contents followed a diurnal pattern which was the inverse of the pH curve. During forage feeding, the cecum contained an average of 2.2 liters (1.6 to 3.4 liters), which turned over 3.9 times per day. When concentrate was fed, cecal volume averaged 3.9 liters (0.6 to 8.6 liters), with a mean liquid turnover of 4.2 times per day. Microbial numbers and pH changes in the pony cecum associated with an abrupt change in diet from hay to concentrate resembled those which occur in the rumen under similar feeding conditions.     

嗜酸乳杆菌MG2_1对大鼠血清脂质代谢的影响研究

利用从蒙古国酸马奶中分离鉴定,并通过耐酸性及体外降胆固醇能力测试筛选获得的L.acidophilusMG2_1菌制备成活菌体和热致死菌体制剂与高脂饲料同时灌喂Wistar系大鼠,研究探讨了对其血清脂质代谢的影响。结果显示,试验第14天时菌活菌体组和热致死菌体组与单纯饲喂高脂饲料对照组比较,对大鼠血清胆固醇浓度的上升分别呈现显著(p<0.05)和极显著的抑制效果(p<0.01),其热致死菌体组大鼠血清HDL_C,显著高于高脂饲料对照组(p<0.05)。并且各试验组大鼠动脉硬化指数均极显著地低于高脂饲料对照组(p<0.01)。热致死菌体组大鼠粪便中总胆汁酸含量也显著高于高脂饲料组(p<0.05)。可见,该菌株具有一定的抑制大鼠血清胆固醇含量上升和预防动脉硬化的作用。但在整个试验期内不改变灌服菌液剂量的情况下,随着试验时间的延长,该菌株对大鼠血清脂质的影响呈减弱趋势。