Fig. 1.
Lactobacillus reuteri DSM 17938 (LR17938) increased survival rate of mouse pups with necrotizing enterocolitis (NEC). Mice (8–10 days old) were separated from their mothers and housed in an incubator. NEC was induced by formula feeding + stress (FS) with hypoxia (5% O2-95% N2 for 10 min) and cold exposure (4°C for 5 min) twice daily for 4 days (indicated by arrows). Live animals were counted on each day for calculation of survival rate. Mice were euthanized on day 5 after NEC protocol (indicated by ×), and tissues were collected. In some cases, pups in the FS group were euthanized on day 3 or 4, if they were in pain, demonstrated labored respirations, or exhibited abdominal distension or gastrointestinal bleeding, to collect tissues for histological analysis and to calculate survival rate. LR17938 [106 colony-forming units (CFU)·g body wt−1·day−1] was added to the formula for treatment (FS + 17938). LR17938 reduced mortality rate on day 5 compared with FS without probiotic. *P = 0.027.