Guttural pouch aspergillus (PAS) (horse TW). Serial section of previous slide for horse TW stained by PAS reveals the presence of fungal hyphae within the inflammatory tissue. Aspergillus spp. is the likely cause of equine guttural pouch mycosis.

Guttural pouch aspergillus (PAS) (horse TW). Serial section of previous slide for horse TW stained by PAS reveals the presence of fungal hyphae within the inflammatory tissue. Aspergillus spp. is the likely cause of equine guttural pouch mycosis.