Abstract

There is little scientific data on analgesic doses in megavertebrates. An online survey posted on the AAZV listserv from September 2012 through March 2013 examined analgesics administered to captive megavertebrates. Compiled data included signalment, drugs administered, dosing regimens, subjective efficacy scores, ease of administration, and any adverse events.

NSAID use data reflects institutions exhibiting hippopotami (Hippopotamus amphibius) and pygmy hippopotamus (Choeropsis liberiensis) (19 total) or giraffe (45 total). Phenylbutazone (12/19 hippopotami institutions, 40/45 giraffe institutions) was the most commonly cited, followed by flunixin meglumine. Doses varied up to 30-fold (1–30 mg/kg) between and within facilities. Subjective efficacy scores ranged from “poor” to “excellent”, with “good” being the most common. Eight out of 64 institutions reported adverse events. Phenylbutazone comprised the most (4/8), including one case of severe gastric ulceration.

Two institutions administered opioids to hippopotami, and seven institutions to giraffe, with tramadol being the most common (4/7 giraffe, 1/2 hippopotami), followed by butorphanol. Efficacy scores varied for tramadol, ranging from “poor” (2/4) to “excellent” (1/4) in giraffe, and a score of “good” for the hippopotamus. Only two adverse events were reported, one of drowsiness in a giraffe, and one of decreased frequency of defecation in a hippopotamus.

Twenty-three of 53 institutions exhibiting giraffe utilized alternative analgesia, including gabapentin, glucosamine/chondroitin, and local anesthetics. Six of 19 institutions exhibiting hippopotami administered omega 3/6 fatty acids, gabapentin, glucosamine/chondroitin, and alpha-2 adrenergics.

Analgesic drug dosages varied greatly among institutions. While all reporting zoological institutions administered similar drugs, there was variation and diversity in dosing regimens.