| nasal and cloacal bacteria in free-ranging desert tortoises from the western united states. | aerobic bacteria were collected from three free-ranging desert tortoise (gopherus agassizii) populations in the eastern mojave desert (arizona, utah; usa) from 1989 to 1993, and from two free-ranging populations in the central sonoran desert (arizona, usa) from 1990 to 1994. six species of nasal bacteria and 18 species of cloacal bacteria were identified. at least one potential pathogen was found in the nasal cavity (pasteurella testudinis), and at least two potential pathogens in the cloaca (ps ... | 2001 | 11310875 |
| 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 |
| a new species of isospora schneider, 1881 (apicomplexa: eimeriidae) from morafka's desert tortoise gopherus morafkai (testudines: testudinidae). | isospora gopheri n. sp. (apicomplexa: eimeriidae) is described from 5 of 28 (18%) morafka's desert tortoise gopherus morafkai murphy, berry, edwards, leviton, lathrop & readle, housed by the phoenix herpetological society, maricopa county, arizona, usa. sporulated oöcysts of this new species were spheroidal to subspheroidal, 20-27 × 19-27 (23.0 × 21.7) µm, with a smooth, bi-layered wall and 1-3 polar granules; an oöcyst residuum was absent. sporocysts were elongate-ovoidal to ellipsoidal, 13-18 ... | 2015 | 26446544 |
| desert tortoise (gopherus agassizii) dietary specialization decreases across a precipitation gradient. | we studied the plant resource use between and within populations of desert tortoise (gopherus agassizii) across a precipitation gradient in the sonoran desert of arizona. the carbon and nitrogen stable isotope values in animal tissues are a reflection of the carbon and nitrogen isotope values in diet, and consequently represent a powerful tool to study animal feeding ecology. we measured the δ(13)c and δ(15)n values in the growth rings on the shells of tortoises in different populations to chara ... | 2013 | 23840495 |
| histomorphometric studies of dermal bone in the desert tortoise, gopherus agassizii. | dermal bone biopsies were collected from the periphery of the carapaces of adult desert tortoises (gopherus agassizii) from grazed and ungrazed habitats near the arizona/utah border (usa). quantitative bone histomorphometry was performed on these biopsies as well as on dermal bone biopsies collected from captive juvenile desert tortoises. except for mild osteomalacia, carapaces of adult desert tortoises from the grazed habitat were relatively normal. no signs of osteopenia were observed. based o ... | 1992 | 1474659 |
| spatial and temporal variation in survival of a rare reptile: a 22-year study of sonoran desert tortoises. | although many species may be vulnerable to changes in climate, forecasting species-level responses can be challenging given the array of physiological, behavioral, and demographic attributes that might be affected. one strategy to improve forecasts is to evaluate how species responded to climatic variation in the past. we used 22 years of capture-recapture data for sonoran desert tortoises (gopherus morafkai) collected from 15 locations across their geographic range in arizona to evaluate how en ... | 2013 | 23011852 |
| hematology and plasma biochemistry reference range values for free-ranging desert tortoises in arizona. | baseline values and ranges for 10 hematologic and 32 plasma chemistry parameters were analyzed for 36 free-ranging sonoran desert tortoises (gopherus agassizzi) collected in yavapai and la paz counties (arizona, usa) from 1990 to 1995. tortoises were radio tagged from 1990 to 1994, and attempts were made to recapture them three times a year. tortoises were weighed, measured, and chemically immobilized to collect blood for hematology and blood chemistry assessments. tortoise biochemistry differed ... | 2002 | 11838205 |