Pathology, physiologic parameters, tissue contaminants, and tissue thiamine in morbid and healthy central Florida adult American alligators (Alligator mississippiensis).
An investigation of adult alligator (Alligator mississippiensis) mortalities in Lake Griffin, central Florida, was conducted from 1998-2004. Alligator mortality was highest in the months of April and May and annual death count peaked in 2000. Bacterial pathogens, heavy metals, and pesticides were not linked with the mortalities. Blood chemistry did not point to any clinical diagnosis, although differences between impaired and normal animals were noted. Captured alligators with signs of neurologic impairment displayed unresponsive and uncoordinated behavior. Three of 21 impaired Lake Griffin alligators were found to have neural lesions characteristic of thiamine deficiency in the telencephalon, particularly the dorsal ventricular ridge. In some cases, lesions were found in the thalamus, and parts of the midbrain. Liver and muscle tissue concentrations of thiamine (vitamin B(1)) were lowest in impaired Lake Griffin alligators when compared to unimpaired alligators or to alligators from Lake Woodruff. The consumption of thiaminase-positive gizzard shad (Dorosoma cepedianum) is thought to have been the cause of the low tissue thiamine and resulting mortalities.
Honeyfield
Dale C
DC
U.S. Geological Survey, Leetown Science Center, Northern Appalachian Research Laboratory, 176 Straight Run Road, Wellsboro, Pennsylvania 16901, USA. honeyfie@usgs.gov
Ross
J Perran
JP
Carbonneau
Dwayne A
DA
Terrell
Scott P
SP
Woodward
Allan R
AR
Schoeb
Trenton R
TR
Perceval
H Franklin
HF
Hinterkopf
Joy P
JP
D000489:Alligators and Crocodiles / Q000378:metabolism; D000818:Animals; D002423:Cause of Death; D005260:Female; D005431:Florida; D006867:Hydrolases / Q000008:administration & dosage* / Q000378:metabolism*; D008297:Male; D009026:Mortality; D009420:Nervous System / Q000473:pathology*; D009460:Neurologic Examination / Q000662:veterinary; D012621:Seasons; D013831:Thiamine / Q000378:metabolism / Q000627:therapeutic use; D013832:Thiamine Deficiency / Q000401:mortality / Q000473:pathology / Q000662:veterinary*
D006867:Hydrolases; C022731:thiaminase II; D013831:Thiamine