Hyperglycemic Effects of Alpha-Two Adrenergic Agonists During Immobilization of Free-Ranging Ring-Tailed Lemurs (Lemur catta)
Diabetes mellitus is an emerging problem in captive ring-tailed lemurs (Lemur catta),4 so it is important to know normal blood glucose values when ring-tailed lemurs are anesthetized and to determine whether any drug effects could cause changes in blood glucose values. Induction with Telazol® and supplementation with medetomidine-butorphanol was shown to be a highly effective protocol for anesthetizing free-ranging ring-tailed lemurs.2 Alpha-two adrenergic agonists, such as medetomidine, are known to cause hyperglycemia in some species,1,3 but other factors, such as stress, may also cause transient hyperglycemia. This study aimed to determine glucose values in free-ranging ring-tailed lemurs both before and after alpha-two agonist administration. Medetomidine-butorphanol supplementation was also compared with dexmedetomidine-butorphanol supplementation due to decreasing commercial access to medetomidine.
Lemurs (n=32) were anesthetized with Telazol® administered via Dan-Inject® blow dart. Once recumbent, they were supplemented via hand-injection with either medetomidine (0.05 mg/kg) and butorphanol (0.25 mg/kg) (n=16) or dexmedetomidine (0.025 mg/kg) and butorphanol (0.25 mg/kg) (n=18). Blood samples were taken from the external saphenous vein immediately before supplementation and 10 min post-supplementation. Initial glucose values varied widely (173±106 mg/dl; min–max=75–540 mg/dl). Four lemurs, two in each group, had decreases in blood glucose post-supplementation, but 28 had increases in glucose post-supplementation. Of those with post-supplementation increases, the lemurs receiving medetomidine had increases of 69±59 mg/dl (min–max=7–217 mg/dl), while those that received dexmedetomidine had increases of 107±60 mg/dl (min–max=56–287 mg/dl).
The authors thank Enafa Efitroatamy, Jacky Youssouf, and A. Reed for their invaluable assistance in capturing lemurs and collecting biomedical information.
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2. Larsen, R.S., A. Moresco, M.L. Sauther, and F.C. Cuozzo. 2008. Field anesthesia of ring-tailed lemurs (Lemur catta) using Telazol, medetomidine, and butorphanol. Abstr. Proc. AAZV and ARAV Conf. Pp. 118–119.
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4. Singleton, C., R.F. Wack, and R.S. Larsen. 2006. Use of hypoglycemic drugs for the management of diabetes mellitus in prosimians. Abstr. Proc. AAZV. P. 379.