Aspergillus spp. are primarily saprophytic fungi, occurring commonly in soils and on other organic and inorganic substrates. The conidia (asexual spores) are hydrophobic and readily airborne with the capacity to germinate in a wide range of conditions. They are thermotolerant, and capable of growth in temperatures ranging from 12 °C to over 50 °C which has contributed to their success as wide ranging opportunistic pathogens in vertebrates ( Bhabhra and Askew, 2005). Aspergillosis is known to occur in all domesticated and in many wild animal species with birds being particularly susceptible to infection ( Tell, 2005). In humans, Aspergillus causes a range of disease including allergic bronchopulmonary disease (ABPV), aspergilloma and various forms of invasive aspergillosis ( Latgé, 1999).