Figure 2.

Oral administration of E. coli O86:B7 protects turkeys against aspergillosis. Clinical examination revealed that A. fumigatus infection produces open-mouthed breathing (OMB) in turkeys treated with PBS or E. coli BL21. Turkeys treated with E. coli O86:B7 were protected from developing OMB (A). Pulmonary lesions (i.e., granulomas, delimited area and white arrow heads) were scored (see methods). Examples of lungs with scores 0 to 3 are shown (B). Granuloma score was lower in turkeys treated with E. coli O86:B7 (C). Lung samples were processed for histopathology and stained with hematoxylin-eosin-saffron (HES, D) and periodic acid-schiff (PAS, E). Histological lesions were scored (see methods). Examples of histopathology samples with scores 0 to 3 are shown. Visible peribronchial regions (asterisk) and granulomas (delimited area and black arrow heads) are shown (HES score, D). The presence of fungal germ-tube/hyphae (black arrows) and mycelium (white arrows) was scored (see methods). Granulomas associated with fungal hyphae (delimited area and black arrow heads) are shown (PAS score, E). HES and PAS scores were lower in turkeys treated with E. coli O86:B7 (F,G). The presence of viable Aspergillus in lungs was quantified by colony-forming unit (CFU) counting assay (H). Fungal DNA levels were measured by A. fumigatus-specific 28S qPCR normalizing against turkey actb and gapdh as host genes using the 2^−ΔΔCt ratio method. Results are relative to 28S levels in the control group (i.e., PBS) (I). No significant change was observed in the amount of CFU and 28S fold change (H,I). Size of bars is indicated. 100X magnification. Results shown are means and standard deviation values. Results were compared by One-way ANOVA with Dunnett’s multiple comparison test applied for individual comparisons (*** p < 0.0001; ns: not significant, 2 experiments, n = 30).