| mycoplasmosis in free-ranging desert tortoises in utah and arizona. | upper respiratory tract disease (urtd) has been associated with major losses of free-ranging desert tortoises (gopherus agassizii) in the southwestern united states. this prompted a clinical examination of 63 free-ranging desert tortoises for signs of urtd and sampling for mycoplasma agassizii, the causative agent of urtd. tortoises were sampled from three sites in the eastern mojave desert (1992-93), and from three sites in the sonoran desert (1992-94). plasma samples were tested for antibodies ... | 2005 | 16456181 |