Abstract
Urinalysis is a non-invasive diagnostic test considered part of the minimum clinical baseline in most mammalian species. Information regarding normal values for healthy, free-ranging Florida manatees (Trichechus manatus latirostris) is limited despite their conservation status1 and frequent admission to rehabilitation centers. Debilitated manatees are often dehydrated, and certain medications of choice are potentially nephrotoxic.2 Additionally, renal disease has been documented in this species without corresponding changes in serum BUN or creatinine3 indicating potential utility for urinary tract monitoring. The objective of this study was to establish urinalysis reference intervals in healthy, free-ranging manatees in the state of Florida, USA. Free-catch urine for complete urinalysis was collected opportunistically using Frisbees®4 from 49 apparently healthy manatees during annual health assessments in Florida from 2017–2019. Mean urine specific gravity was 1.009 (SD ±0.009), similar to captive Florida manatees,5,6 Amazonian manatees,7 and Asian elephants8. Urine was predominantly alkaline (pH 8.5, 57%), pale or medium yellow (78%), and clear (84%). The majority of animals had trace protein on dipstick (76%), but when performed (n=13), follow-up sulfosalicylic acid was negative. Glucose and ketones were negative for all animals. Examination of urine sediment showed low cellularity, no red or white blood cells, and a small amount of amorphous crystals (65%). Incidental findings included diatoms (82%), rhabditoid nematode larvae (22%), tanaids (2%), and sperm (2%). Our dataset provides baseline urinalysis data for a healthy population of wild manatees that will be beneficial for monitoring individuals during rehabilitation, in addition to other clinical and research settings.
Acknowledgements
The authors wish to thank the capture and assessment teams of the U.S. Geological Survey (USGS), the Florida Fish and Wildlife Conservation Commission (FWC), and the University of Florida Aquatic Animal Health Program (UFAAH). All research was conducted under USFWS research permits issued to the USGS, FWC, and UFAAH and under approval of IACUC sample collection standards for wildlife.
*Presenting author
+Student presenter
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