Table 5.
Identification of the colonies isolated from breast milk and feces from breast- and formula-fed infants
| Milk | Breast-fed infants | Formula-fed infants | |
| Microorganisms | N° colonies (%) | N° colonies (%) | N° colonies (%) |
| 1. Gram-positive bacteria: | |||
| Staphylococcus epidermidis | 304 (62.16) | 140 (26.36) | 3 (1.57) |
| Other staphylococci | 24 (4.91) | 21 (3.95) | 3 (1.57) |
| Enterococcus faecalis | 21 (4.29) | 69 (12.99) | 84 (44.21) |
| Other enterococci | 1 (0.20) | 6 (1.12) | 16 (8.42) |
| Streptococcus spp. | 35 (7.15) | 17 (3.20) | NDa |
| Bifidobacterium spp. | 4 (0.81) | 74 (13.93) | 3 (1.58) |
| Lactobacillus spp. | 2 (0.40) | 6 (1.13) | 15 (7.89) |
| Other Gram-positive bacteriab | 22 (4.49) | 31 (5.83) | ND |
| 2. Gram-negative bacteria: | |||
| Acinetobacter johnsonii | 5 (1.03) | ND | ND |
| Bacteroides spp. | ND | 6 (1.13) | 2 (1.05) |
| Burkholderia spp. | 2 (0.40) | 5 (0.95) | ND |
| Citrobacter spp. | 7 (1.44) | 4 (0.75) | 5 (2.63) |
| Escherichia coli | 37 (7.56) | 94 (17.70) | 50 (26.32) |
| Klebsiella spp. | 7 (1.44) | 23 (4.33) | 3 (1.58) |
| Pantoea agglomerans | ND | ND | 2 (1.05) |
| Enterobacter spp. | 7 (1.44) | 30 (5.64) | 4 (2.10) |
| Other Gram-negative bacteriac | 11 (2.25) | 5 (0.95) | ND |
| Total number of colonies identified | 489 | 531 | 190 |
aND, not detected; bOther Gram-positive bacteria: Actinomyces spp., Kocuria spp., Propionibacterium spp.; cOther Gram-negative bacteria: Kluyvera cryocescens, Pseudomonas spp., Shigella spp.