“…Although O. rhinotracheale is considered as a primary pathogen in poultry (van Veen et al, 2000b;Pan et al, 2012), the severity of clinical signs, duration of the disease, and mortality are extremely variable and are influenced by housing environmental stressors such as poor management, inadequate ventilation and high ammonia levels, high stocking density, poor litter conditions, poor hygiene, foodborne mycotoxins, suboptimal nutrition, and concomitant infectious diseases Hoerr, 2010). After its identification and characterization in 1994 by Charlton et al, O. rhinotracheale has been isolated throughout the world Devriese et al, 1995;van Empel et al, 1997;Goovaerts et al, 1998;Sakai et al, 2000;Sprenger et al, 2000;van Veen et al, 2000a;Ak and Turan, 2001;Devriese et al, 2001;Hung and Alvarado, 2001;Soriano et al, 2002;Malik et al, 2003;Banani et al, 2004;Canal et al, 2005;Türkyilmaz, 2005;Tsai and Huang, 2006;Marien, 2007;Chansiripornchai et al, 2007;Moreno et al, 2008;Murthy et al, 2008b;Uriarte et al, 2009;Walters et al, 2009;Gavrilović et al, 2010;Tabatabai et al, 2010;Chernyshev et al, 2011;Gornatti Churria et al, 2011;.…”