Effectiveness of antagonists for tiletamine-zolazepam/xylazine immobilization in female white-tailed deer.
A combination of tiletamine-zolazepam/xylazine (TZ/X) is effective in the chemical immobilization of white-tailed deer (Odocoileus virginianus); however, the lengthy duration of immobilization may limit its usefulness. From October to November 2002, 21 captive female deer were assigned randomly to an alpha(2) antagonist treatment to reverse xylazine-induced sedation (seven does per group). All deer were given 220 mg of TZ (4.5+/-0.4 mg/kg) and 110 mg of X (2.2+/-0.2 mg/kg) intramuscularly (IM). Antagonist treatments were either 200 mg of tolazoline (4.0+/-0.4 mg/kg), 11 mg of atipamezole (0.23+/-0.02 mg/kg), or 15 mg of yohimbine (0.30+/-0.02 mg/kg) injected, half intravenously and half subcutaneously, 45 min after the IM TZ/X injection. In addition, 10 other deer (five per group) were immobilized as before and then given tolazoline (200 mg) after 45 min, with either a carrier (dimethyl sulfoxide [DMSO]) or carrier (DMSO) plus flumazenil (5 mg) to reverse the zolazepam portion of TZ. Mean times from antagonist injection until a deer raised its head were different for alpha(2) antagonist treatments (P=0.02). Times were longer for yohimbine (62.3+/-42.7 min) than for either atipamezole (24.3+/-17.1 min) or tolazoline (21.3+/-14.3 min). Mean times from antagonist injection until standing were not different (P=0.15) among yohimbine (112.0+/-56.4 min), atipamezole (89.7+/-62.8 min), or tolazoline (52.6+/-37.2 min). A sedation score based on behavioral criteria was assigned to each deer every 30 min for 5 hr. On the basis of sedation scores, tolazoline resulted in a faster and more complete reversal of immobilization. Flumazenil treatment did not affect recovery.
Department of Forestry, Wildlife and Fisheries, University of Tennessee, 274 Ellington Hall, Knoxville, Tennessee 37996, USA.
Brad F
BF
Miller
Lisa I
LI
Muller
Tom
T
Doherty
David A
DA
Osborn
Karl V
KV
Miller
Robert J
RJ
Warren
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000777:Anesthetics / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D000818:Animals; D003670:Deer / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005260:Female; D005442:Flumazenil / Q000494:pharmacology; D018757:GABA Modulators / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D007103:Immobilization / Q000379:methods / Q000662:veterinary*; D011897:Random Allocation; D013992:Tiletamine / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D013997:Time Factors; D014043:Tolazoline / Q000494:pharmacology; D014991:Xylazine / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D015016:Yohimbine / Q000008:administration & dosage / Q000494:pharmacology; D015041:Zolazepam / Q000008:administration & dosage / Q000037:antagonists & inhibitors*
D000316:Adrenergic alpha-Agonists; D000777:Anesthetics; D004338:Drug Combinations; D018757:GABA Modulators; D007093:Imidazoles; C050701:atipamezole; D014991:Xylazine; D015016:Yohimbine; D013992:Tiletamine; D005442:Flumazenil; D014043:Tolazoline; D015041:Zolazepam