Vitamin A concentrations in serum and liver from Florida panthers

Many of the anomalies and clinical signs afflicting the Florida panther (Fe lis concolor coryi) are suggestive of vitamin A deficiency. Our objectives in this study were to determine if a vitamin A deficiency exists in the fre e-ranging panther population and to determine if there are differences in v itamin A levels among various subgroups of free-ranging panthers. Retinol c oncentrations were used as an index to Vitamin A concentrations and were de termined in serum and liver from free-ranging (serum, n = 45; liver, n = 22 ) and captive (serum, n = 9; liver,n = 2) juvenile and adult Florida panthe rs from southern peninsular Florida (USA), and in liver from free-ranging c ougars (F. concolor subspp.) from Washington (USA) and Texas (USA) between November 1984 and March 1994. Combined juvenile (6- to 24-mo-old) and adult (>24-mo-old) free-ranging Florida panthers had mean +/-SD serum retinol co ncentrations of 772.5 +/- 229 pmol/ml. Adult free-ranging Florida panthers had mean liver retinol concentrations of 4794.5 +/- 3747 nmol/g. Free-rangi ng nursing Florida panther kittens (age <1 mo) had mean serum retinol conce ntrations of 397.9 +/- 69 pmol/ml. Among subgroups of free-ranging Florida panthers, females had higher corrected mean serum retinol concentrations th an males and adult free-ranging Florida panthers had higher mean liver reti nol concentrations than juveniles. Retinol concentrations in free-ranging F lorida panthers did not differ significantly from those in captive panthers (liver and serum) or other free-ranging cougars (liver). Based on limited published values and our controls, a vitamin A deficiency could not be demo nstrated in the Florida panther population nor were any subgroups or indivi duals considered deficient.