EVALUATION OF TWO ANESTHETIC COMBINATIONS IN LOWLAND NYALA (TRAGELAPHUS ANGASII).

Fourteen lowland nyala (Tragelaphus angasii) in managed care were successfully anesthetized for a total of 17 anesthetic events using either a combination of butorphanol (0.75 ± 0.15 mg/kg), azaperone (0.25 ± 0.05 mg/kg), and medetomidine (0.30 ± 0.06 mg/kg) (BAM) or medetomidine (0.17 ± 0.01 mg/kg), azaperone (0.22 ± 0.02 mg/kg), and alfaxalone (0.52 ± 0.08 mg/kg) (MAA) delivered intramuscularly via dart. Mean time to initial effect, sternal recumbency, lateral recumbency, handling, and intubation were recorded. The nyala were maintained in sternal recumbency with supplemental oxygenation until 60 min after initial injection. Cardiopulmonary effects were recorded every 5 min after handling until reversal. Arterial blood samples were collected every 15 min for analysis. Level of sedation and quality of recovery were scored. Anesthesia was antagonized with atipamezole (at 5 mg per mg of medetomidine) for both protocols and naltrexone (at 2 mg per mg of butorphanol) for the BAM protocol delivered intramuscularly via hand injection. Mean time to extubation, head control, and standing post reversal were recorded. No hyperthermia, acidemia, apnea, or tachycardia occurred; however, animals did display hypoxemia. Two animals in the BAM cohort required supplementation to facilitate handling. These drug combinations provided satisfactory levels of sedation in most cases for safe handling and minor procedures in lowland nyala under managed care.

SUCCESSFUL REPAIR OF ANTEBRACHIAL FRACTURES WITH EXTERNAL SKELETAL FIXATION IN THREE MACROPODS.

Three captive macropods comprising three different species sustained unilateral antebrachial fractures. All fractures were assumed to be trauma related, although the specific circumstances surrounding each case was unknown. Each fracture was surgically repaired with type Ia (unilateral, monoplanar) external skeletal fixators, which were all removed approximately 3 mo postoperatively. Although each animal experienced at least one complication, all animals showed adequate bridging and remodeling at the fracture sites and had good-to-excellent return to normal function after fixator removal. This case series is the first to describe the successful repair of antebrachial fractures using external skeletal fixation in captive macropods and details some of the complications that can occur with postoperative management of captive animals.

RENAL EVALUATION IN CHOLOEPUS SPECIES.

Two species of sloths in the family Megalonychidae, Hoffmann's (Choloepus hoffmanni) and Linnaeus's (Choloepus didactylus) two-toed sloths, are commonly held in zoological institutions. Despite frequent published reports of urinary tract disease in these species, reports of diagnostics are mostly limited to descriptions of hematology and serum chemistry. In this study, repeated urinalysis, urinary chemistry, serum chemistry, and radiographs were collected opportunistically from six Hoffmann's and five Linnaeus's sloths. Proteinuria, bacteriuria, low urine specific gravity, and crystalluria were common in the absence of other signs of urinary tract pathology.

Reference values for hematology, plasma biochemical analysis, plasma protein electrophoresis, and Aspergillus serology in elegant-crested tinamou (Eudromia elegans).

Elegant-crested tinamou (Eudromia elegans) are members of the family Tinamidae. A review of postmortem records at the Saint Louis Zoo suggests that this species is highly susceptible to aspergillosis. Antemortem detection of Aspergillus infections can be aided by evaluating results of hematologic, plasma biochemical, protein electrophoretic, and Aspergillus antigen and antibody serologic testing. To establish species-specific reference intervals for these parameters in elegant-crested tinamou, blood samples were collected and analyzed from 19 healthy captive adult and subadult elegant-crested tinamou. The predominant circulating leukocyte in elegant-crested tinamou is the lymphocyte. Prealbumin electrophoresis fractions were detected in 4 of 19 birds (21%), and globulin fractions were detected in all birds. All birds had measurable titers for Aspergillus antibody and galactomannan antigen, including 3 birds with antibody levels considered to be positive. Galactomannan levels were all below the positive threshold of 1.0. Results of hematologic and plasma biochemical analyses performed on blood samples obtained from terminally ill elegant-crested tinamou with confirmed aspergillosis were compared with results from healthy individuals. Significant differences were found in the hematocrit, total white blood cell count, heterophil and monocyte counts, and albumin and globulin levels.

Fecal steroid analysis for evaluating ovarian function in the greater kudu (Tragelaphus strepsiceros) and lesser kudu (Tragelaphus imberbis).

Seasonal reproductive-endocrine norms have not been described for the genus Tragelaphus, which consists of seven species of African antelope. Longitudinal patterns of progesterone metabolite excretion were assessed by radioimmunoassays in fecal samples collected noninvasively (three to seven samples per week) from greater kudu (Tragelaphus strepsiceros, n = 4) and lesser kudu (Tragelaphus imberbis, n = 4). Progesterone metabolite excretion patterns revealed seasonal estrous cycles in both species, and discrimination of pregnant versus nonpregnant females was achieved in lesser kudu. These data reveal the value of fecal progesterone metabolites for establishing reproductive-endocrine norms in both zoo-maintained and free-living antelopes of the genus Tragelaphus.

Cardiac assessment of African hedgehogs (Atelerix albiventris).

Cardiomyopathy is a common finding in captive African hedgehogs (Atelerix albiventris) at postmortem exam. To date, treatment attempts have been mostly empirical and unrewarding. The objective of this study was to determine reference cardiac values for captive African hedgehogs based on echocardiogram, electrocardiogram (ECG), and radiographs. Adult African hedgehogs with no clinical signs of cardiac disease (n = 13) were selected. Each animal was anesthetized with isoflurane via facemask and an echocardiogram, ECG, and radiographs were performed. Standard measurements were taken and the descriptive statistics performed. Values were comparable to limited data available in other hedgehog species and other similar-sized exotic species. Two animals were removed from consideration of reference values due to valvular defects that were considered significant. These data are the first establishing cardiac parameters in normal African hedgehogs using radiographic cardiac measurement, echocardiogram, and ECG. Evaluating animals with possible cardiomyopathy may allow for earlier diagnosis and more successful treatment.

Hematologic parameters in raptor species in a rehabilitation setting before release.

To be considered for release, raptors undergoing rehabilitation must have recovered from their initial injury in addition to being clinically healthy. For that purpose, a good understanding of reference hematologic values is important in determining release criteria for raptors in a rehabilitation setting. In this study, retrospective data were tabulated from clinically normal birds within 10 days of release from a rehabilitation facility. Hematologic values were compiled from 71 red-tailed hawks (Buteo jamaicensis), 54 Eastern screech owls (Megascops asio), 31 Cooper's hawks (Accipiter cooperii), 30 great-horned owls (Bubo virginianus), 28 barred owls (Strix varia), 16 bald eagles (Haliaeetus leucocephalus), and 12 broad-winged hawks (Buteo platypterus). Parameters collected included a white blood cell count and differential, hematocrit, and total protein concentration. Comparisons were made among species and among previously published reports of reference hematologic values in free-ranging birds or permanently captive birds. This is the first published report of reference values for Eastern screech owls, barred owls, and broad-winged hawks; and the first prerelease reference values for all species undergoing rehabilitation. These data can be used as a reference when developing release criteria for rehabilitated raptors.

Pharmacokinetics of tramadol hydrochloride and its metabolite O-desmethyltramadol in peafowl (Pavo cristatus).

Tramadol is a centrally acting opiate analgesic that has not been well studied in avian species. Tramadol and its metabolites exert their effects at multiple sites, including opiate (mu, kappa, and delta), adrenergic (alpha-2), and serotonin (5HT) receptors. This multi-receptor mode of action is advantageous for avian patients because the mechanisms for analgesia have not been fully elucidated in all species. The objective of this study was to document the pharmacokinetics of tramadol and its active metabolite O-desmethyltramadol (M1) in common peafowl (Pavo cristatus). Based on results from a pilot animal, six adult peafowl (three male, three female) judged to be clinically healthy based on physical exam and routine bloodwork were selected for this study. Each bird was anesthetized for placement of a jugular catheter, and 7.5 mg/kg tramadol was administered orally via gavage tube. Blood samples were collected just prior to drug administration; at 30 min; and at 1, 2, 3, 4, 6, 8, 10, 12, 24, and 34 hr. Plasma levels of tramadol and M1 were measured and the pharmacokinetics for each drug was calculated. Although tramadol was quickly metabolized, plasma levels of M1 remained at or near human analgesic levels for 12-24 hr. Based on these data, tramadol may be a practical option as an orally administered analgesic agent in avian patients. Further studies, including antinociceptive studies, are needed.