Effect of ingested Lactobacilli on Salmonella infantis and Escherichia coli and on intestinal flora, pasted vents, and chick growth.

Experiments were conducted to evaluate the use of lactobacilli (LB) in poultry medicine. These were the findings: (1) the numbers of LB and Escherichia coli present in the ceca of newly hatched chicks from the same hatchery had marked variation among hatches; (2) LB inoculated into the crop a few hours after hatching did not induce a reduction of Salmonella infantis in the cecal contents; (3) a single dose of LB given at one day after hatching did not appear to alter the LB-coliform balance in the cecum; (4) in one group of fasted chicks, LB inoculation prevented accumulation of excreta around the vents; (5) prophylactic feeding of the bacillus to non-stressed chicks averted pasted vents; (6) continuous feeding of LB produced a numerical increase of body weight that was not statistically significant in the small groups of birds utilized; (7) poults hatched from medicated eggs had a low LB count in the cecum, and crop instillation of LB at one day of age did not change the cecal LB-coliform flora at 9 days of age in treated and untreated groups; (8) LB that had an initial viable count of 10(9) and was held at room temperature in tap water remained at that titer for 23 days; and (9) various numerical combinations of LB and E. coli in the stationary phase of growth did not, at any concentration of either organism, depress viability of the other.