Using axenic quails fed a diet containing lactose, we have investigated the potentially pathogenic roles of six Clostridium butyricum strains of human origin. Three strains (CB155-3, CB1002, and CB203-1) isolated from neonatal necrotizing enterocolitis patients and two of three strains (CB19-1 and CB25-2) isolated from healthy newborns led to cecal or crop lesions or both similar to those observed in human neonatal necrotizing enterocolitis: thickening of the cecal wall with gas cysts, hemorrhagic ulcerations, and necrotic areas. The lactose-negative strain (CB46-1) did not develop any lesions. The neuraminidase-producing strain (CB155-3) caused lesions in all monoassociated quails, whereas the other strains caused lesions in 28 to 85% of animals. Removal of dietary lactose suppressed all pathological incidence. These results show that lactose fermentation is a prerequisite in these pathological changes and stress the roles played by both the strain and the host in the expression of C. butyricum enteropathogenicity.Clostridium butyricum is frequently isolated from feces of healthy human newborns (6, 10, 29), but the role played by this strain in neonatal necrotizing enterocolitis (NNE) has been questioned by several authors (6,10,11,13,29,30). Nevertheless, no enteropathogenic toxin has ever been attributed to C. butyricum.Popoff et al. (21) were the first to reproduce, in the ceca of chickens monoassociated with C. butyricum strains, histopathological lesions (congestion, hemorrhage, necrosis, and pneumatosis) similar to those observed in human newborns suffering from NNE. However, because of their large size, chickens are not practical animals to use for further investigation in isolators.Ulcerative (18) and necrotic (3) enteritises have been observed in quails. Their small size and fast growth rate encouraged us to test them as an experimental model for the study of C. butyricum enteropathogenicity. We tested three strains isolated from NNE patients; one strain had already been tested in chickens (21). We have also tested three other strains isolated from healthy newborns. MATERIALS AND METHODS Bacterial strains. Of six C. butyricum strains studied, three were isolated from sick premature human newborns: strain CB1002 from a fatal NNE case, strain CB203-1 from a patient with hemorrhagic colitis, and strain CB155-3 from an NNE patient. The three remaining strains, CB19-1, CB25-2, and CB46-1, were isolated from stools of healthy premature newborns (19). Strain CB1002 was used in a previous study (21). CB155-3 was the sole neuraminidase-producing strain (19), and CB46-1 was the sole lactose-nonfermenting strain. Strains were grown in TY broth (Pasteur Production, Paris, France).Maintenance and inoculation of quails. Quails (Coturnix coturnix subsp. japonica) were obtained by the method of Reynier and Sackteder (23) with the following modifications * Corresponding author. for germfree animals. Eggs from a conventional flock kept in a laying battery were collected twice daily and immediately brushed with 0.3% quate...

Summary. The aim of this work was to investigate the effects on bile secretion of flow rate and site of reinfusion of the collected bile to the animal. Thirty-two pigs weighing 50 ± 3 kg at the beginning of the experiment were fitted with a reentrant fistula in the lower common bile duct and in the upper duodenum. Bile collected from the bile duct was reinfused in four different ways (four groups of 8 animals each) : into the duodenum or the lower common bile duct at a constant flow rate using a peristaltic pump, or into the duodenum or the lower common bile duct at a rate mimicking the flow rate of the secretion using an automatic apparatus.Reinfusing the bile into the lower common bile duct at a rate mimicking the secretion rate provided a daily bile acid production about 21 % higher than the level recorded with the other three methods. This was mainly due to a higher bile acid concentration since the bile flow was only slightly affected by the treatment.Introduction.

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