Food supplementation with milk fermented by Lactobacillus casei DN-114 001 protects suckling rats from rotavirus-associated diarrhea.

Group A rotavirus is the leading cause of diarrhea among children aged 3-36 mo worldwide. Introducing fermented milk products into the infant diet has been proposed for the prevention or treatment of rotavirus diarrhea. The preventive effect of milk fermented by the Lactobacillus casei strain DN-114 001 was studied in a model of germfree suckling rats supplemented daily from d 2 of life and infected with SA11 rotavirus at d 5 (RF group). One group was supplemented with nonfermented milk (RM) and two uninfected groups (CM and CF) received either nonfermented or fermented milk. Frequency and severity of diarrhea were observed. Rats were killed at various times from 0 to 120 h postinfection (p.i.). Bacteria were measured in the intestine, and rotavirus antigens were detected by ELISA in fecal samples and in different parts of the intestine. Histologic observations were made, including vacuolation, morphology of intestinal villi and number of mucin cells. RM rats had diarrhea for 6 d; compared with the CM group, they had alterations of the intestinal mucosa characterized by cellular vacuolation 48 and 72 h p.i. and a lower number of sulfated mucin cells 72 and 96 h p.i. (P: < 0.05). Early supplementation with fermented milk significantly decreased the clinical signs of diarrhea from 24 to 144 h p.i. (P: < 0.05) and prevented rotavirus infection in all sections of the intestine. Histologic lesions of the small intestine were greatly reduced (P: < 0.05) and the number of mucin cells remained unchanged. The data are discussed with respect to the possibility of reducing rotavirus diarrhea in young children by consumption of fermented milk.

Development of a heterologous model in germfree suckling rats for studies of rotavirus diarrhea.

Germfree suckling rats were infected with an SA11 rotavirus strain. Infected pups developed diarrhea associated with histopathological changes. The virus was detected in feces and in the small intestine. Cellular vacuolation was observed in the villi of the jejunum. These results provide a new model for further investigations of group A rotavirus infection.

Milk fermented with yogurt cultures and Lactobacillus casei compared with yogurt and gelled milk: influence on intestinal microflora in healthy infants.

Ingestion of fermented dairy products induces changes in the equilibrium and metabolism of the intestinal microflora and may thus exert a healthful influence on the host. We compared the effects of consumption of a traditional yogurt, a milk fermented with yogurt cultures and Lactobacillus casei (YC), and a nonfermented gelled milk on the fecal microflora of healthy infants. Thirty-nine infants aged 10-18 mo were randomly assigned to one of three groups in which they received 125 g/d of one of the three products for 1 mo. The following indexes were not modified during the supplementation period or for 1 wk after the end of supplementation: total number of anaerobes, bifidobacteria, bacteroides, and enterobacteria; pH; water content; concentrations of acetate, butyrate, propionate, and lactate; and bacterial enzyme activity of beta-galactosidase and alpha-glucosidase. In contrast, in the yogurt group the number of enterococci in fecal samples increased (P < 0.05), whereas the percentage of branched-chain and long-chain fatty acids, which are markers of proteolytic fermentation, decreased (P < 0.05). In the YC group, the percentage of children with > 6 log10 colony-forming units lactobacilli/g feces increased (P < 0.05), whereas the potentially harmful enzyme activity of beta-glucuronidase and beta-glucosidase decreased (P < 0.05). These decreases were particularly marked in those infants in the YC group in whom activity of the enzymes was initially unusually high.

Pattern of metabolism and composition of the fecal microflora in infants 10 to 18 months old from day care centers.

BACKGROUND: From 5 months of age, infants are progressively introduced to a variety of foods which influence the equilibrium of the intestinal microflora. METHODS: Thirty-five children age 10-18 months from 8 day care centers in France were studied. Fecal specimens were examined for their biochemical and microbiological criteria. RESULTS: Bifidobacteria and Bacteroides belong to the predominant populations (9.7 and 8.6 log 10 cfu/g, respectively). The mean level of enterobacteria and enterococci were 8.0 and 7.8 log 10 cfu/g, respectively. Only 10% of the infants presented a lactobacilli amount above 6 log 10 cfu/g. Most feces had similar pH values (mean 6.4), percentage of water (mean 76.4%), and short chain fatty acid, ammonia and lactic acid concentrations (means 77, 6.7 and 2.3 mumol/g, respectively). beta-galactosidase had the highest activity (106 IU/g of protein) and nitroreductase, the lowest (0.1 IU/g of protein). alpha-glucosidase and nitrate reductase showed intermediate values of 17 and 4 IU/g of protein, respectively. With the exception of 4 infants, beta-glucosidase and beta-glucuronidase values were low (4 and 2 IU/g of protein). Age and day care center were not significant factors for most parameters studied, except that rotavirus was related to day care center, with detection in 5 infants from the same center. CONCLUSIONS: Many biochemical parameters were comparable to those found in adults, with the exception of ammonia concentration and beta-galactosidase activity. The fecal bacterial profile was different than in adults, with more Bifidobacteria than Bacteroides and higher levels of facultative anaerobes. One infant suffering from gastroenteritis had distinctive biochemical and bacterial parameters.