Pharmacokinetics of Transdermal Flunixin Meglumine Following a Single Dose in Marine Toads (Rhinella marina)

Analysis of Circulating Fatty Acid Profiles in Free-Ranging and Managed Care Marine Toads (Rhinella marina) with a Comparison of Whole-Blood Vial and Whole-Blood Dried Blood Spot Card Analyses

This study provides novel data on circulating concentrations of whole-blood fatty acids (FAs) in marine toads (Rhinella marina) via dried blood spot (DBS) card technology as a potential amphibian model species. Free-ranging (n = 10) animals were compared to managed populations fed two diet strategies for 60 days (n = 6 per diet). Thirty-six individual FAs were analyzed, with 28 found in significant reportable quantities. Eight FA groupings were represented. Traditional whole-blood vial (WBV) FA percentages were also collected and compared to DBS after managed care for 60 days. Results showed eleven individual FAs and four FA groups were higher in free-ranging toads (n = 10; p ≤ 0.05), while three FAs and three groups were higher in managed care (n = 12; p ≤ 0.05). FA concentrations compared between DBS cards and WBV at day 60 generally agreed, although two individual FAs and one grouping were higher in DBS (p ≤ 0.05). When free-ranging FAs were analyzed by sex, four individual FAs and two groupings were higher in females, while four individual FAs and one grouping were higher in males. Understanding normal FA circulating levels and how husbandry changes them may impact amphibian health. Additionally, DBS cards may provide a convenient sampling tool for fieldwork.

URINARY CORTICOSTERONE CONCENTRATIONS IN FREE-RANGING AND MANAGED CANE TOADS (RHINELLA MARINA)

Approximately 40% of amphibian species are threatened with extinction. The welfare of amphibians maintained under managed care as assurance populations is of vital importance to guard against extinction and provide a viable source population for future reintroduction. To manage amphibian species properly ex situ, it is important to understand how stress levels change over time when animals are removed from the wild and placed into managed environments. Corticosterone was analyzed in urine samples from free-ranging cane toads (Rhinella marina, n = 55) in Miami, FL, and under managed care for 22 (n = 48), 50 (n = 11), 81 (n = 25), or 119 (n = 10) days. Concentrations of corticosterone in free-ranging toad urine averaged 1.74 ± 0.195 ng/ml urine specific gravity (sp. gr.), which was greater (P < 0.05) than other time points (day 22: 0.77 ± 0.114 L; day 81: 0.85 ± 0.191 ng/ml sp. gr.; day 119: 0.58 ± 0.093 ng/ml sp. gr.), except day 50 (0.91 ± 0.274 ng/ml sp. gr.), which was not different from free-ranging or managed care values. Thus, corticosterone was lower in cane toads under managed care compared with those sampled in the wild, suggesting that managed care is not a stressor for this species.