Abstract

Three ring-tailed lemurs (Lemur catta) and one Bengal slow loris (Nycticebus coucang bengalensis) were diagnosed with diabetes mellitus. The diet of each animal was modified to reduce sugar content. For management reasons, animals were treated with oral hypoglycemic drugs rather than exogenous insulin. Drugs used alone, or in combination, included glipizide (GlipiZIDE, Sandoz, Inc., Broomfield, CO, USA; 0.38–2 mg/kg PO BID), metformin hydrochloride (Mutual Pharmaceutical Company, Inc., Philadelphia, PA, USA; 48 mg/kg PO BID), and acarbose (Precose®, Bayer Pharmaceuticals Corporation, West Haven, CT, USA; 1.9–3.7 mg/kg PO BID). Parameters used to evaluate glycemic control included urine glucose, blood glucose, serum fructosamine, glycosylated hemoglobin,¹ serum insulin, and serum insulin-to-glucose ratio (I:G). Routine monitoring of glycemic control and alteration of drug therapy for each animal are ongoing.

During treatment with glipizide, glycemic parameters improved in the loris and lemur 1 (initial I:G of 31 and 28, respectively). However, glycemic parameters did not improve in lemur 2 and lemur 3 (initial I:G of 1 and 5, respectively) when treated with glipizide, metformin, and/or acarbose. Monitoring serum insulin and I:G in diabetic prosimians may be valuable for predicting response to certain classes of hypoglycemic drugs. Oral hypoglycemic drugs that stimulate insulin release and/or improve peripheral insulin sensitivity will be most effective in patients with adequate endogenous insulin and normal or high insulin-to-glucose ratio (lemur 1 and loris). Normal reference ranges for fructosamine, insulin, and I:G in prosimians would be helpful in managing clinical cases of diabetes in these species.

Literature Cited

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