Fungal detection in TW
Overall, a positive TW cytology was obtained in 75.5% (117/155) of
horses (Table 1). Proportion of samples positive for fungi on
cytological examination was significantly lower in the SA group than in
CTL (P = 0.007) and MA (P < 0.001) groups (Table 1; Figure
1A). Similarly, the proportion of fungi phagocytosed by macrophages was
significantly lower in the SA group than the CTL (P = 0.02) and MA (P =
0.01) groups. The proportion of spores or hyphae (phagocytosed or not)
was not significantly different between groups.
Overall, a positive TW mycology was obtained in 81.9% (127/155) of all
horses. Proportion of samples positive for fungi by culture was
significantly higher in the MA group than the CTL group (P = 0.005)
(Figure 1B). In the TW, 17 fungal genera were identified, with
the most commonly isolated genera being Aspergillus sp.
(80/127, 63%), Penicillium sp. (66/127, 52%), andChrysosporium sp. (45/127, 35.4%), alone or in combination with
other fungi (Table S1). Culture allowed identification of 7 species ofAspergillus sp., alone or in combination with other species:A. nidulans (n=35), A. fumigatus (n=29), A. niger(n=15), A. glaucus (n=14), A. terreus (n=6), A.
versicolor (n=6) and A. flavus (n=2).
The number of fungal genera concomitantly identified according to
samples and group is available in Figure 2. Aspergillus sp. was
identified in 54.2% (13/24) of CTL horses, 68.4% (52/76) of MA horses
and in 55.6% (15/27) of SA horses, with no significant difference
between groups. Proportions positive for Penicillium sp. were not
significantly different between groups; this genus was found in 66.7%
(16/24) of CTL horses, in 47.4% (36/76) of MA horses and in 51.9%
(14/27) of SA horses. Similarly, proportions of Chrysosporium sp.
did not differ significantly between groups, with 33.3% (8/24) in CTL
horses, 36.8% (28/76) in MA horses and 33.3% (9/27) in SA horses.