Pinniped electroencephalography: Methodology and findings in California sea lions (Zalophus californianus).

This study was designed to identify abnormalities in the electroencephalograms (EEGs) recorded from stranded California sea lions (Zalophus californianus) with suspected domoic acid (DA) toxicosis. Recordings from animals presenting for non-neurological issues were also obtained to better understand the normal EEG (background activity and transient events) in this species, as, to date, studies have focused on examining natural sleep in pinnipeds. Most animals were sedated for electrode placement and EEG acquisition with some receiving antiepileptic medications or isoflurane during the procedure. A total of 103 recordings were read and scored from 0 (normal) to 3 (severely abnormal). Epileptiform discharges, consisting of spikes, sharp waves, slow waves, and/or spike waves, were present in all EEGs with scores of 1, 2, or 3. The distribution of these events over the scalp varied. While often generalized, others were lateralized over one hemisphere, bifrontal, bioccipital, and/or bitemporal, while some discharges were multifocal. Findings were different between sea lions and occasionally changed within the EEG on a given sea lion. No clinical seizures were observed during the recording but a few sea lions had findings consistent with electroencephalographic seizures. When available, supporting diagnostic results obtained from magnetic resonance imaging (MRI) and/or necropsy/histopathology were described, as well as the status of those sea lions that recovered and were released with satellite tags.

RETROSPECTIVE ANALYSIS AND VALIDATION OF SERUM SYMMETRIC DIMETHYLARGININE (SDMA) CONCENTRATIONS IN CHEETAHS ( ACINONYX JUBATUS).

Kidney disease is common among captive cheetahs ( Acinonyx jubatus). Serum creatinine is the most common measurement to estimate glomerular filtration rate (GFR) because of the ease of its clinical use, but it is a crude estimate that only increases after significant disease is already present and is affected by extrarenal factors. Symmetric dimethylarginine (SDMA) is a renal biomarker in humans, dogs, and cats that correlates with serum creatinine and GFR and appears to be an earlier and more specific biomarker for kidney disease. Ninety-two banked serum samples from 11 cheetahs housed at the Oklahoma City Zoo from 1992 to 2012 were retrospectively analyzed. Histopathology results were available for 10/11 cheetahs, and all 10 had histologic renal lesions. General categories of renal lesions included glomerulosclerosis (7/10; 70%), amyloidosis (7/10; 70%), inflammatory (9/10; 90%), and oxalate nephrosis (2/10; 20%). SDMA immunoassay and mass spectrometry were measured for validation and compared with creatinine to assess for correlation. Serum creatinine concentrations were determined by enzymatic colorimetric methods. SDMA immunoassay was validated in cheetahs and correlated well with serum creatinine ( R2=0.687; P < 0.0001). SDMA and serum creatinine measured from freeze-thawed stored samples show high correlation in individual cheetahs ( R2 = 0.972; P < 0.0001). These data support that SDMA could be a promising renal biomarker in cheetahs. Further research is warranted to investigate whether SDMA might be an earlier indicator of kidney disease in cheetahs and whether this assay can be extended to other nondomestic carnivores.

Management of a Nonhealing, Superficial Corneal Ulcer in a Hyacinth Macaw (Anodorhynchus hyacinthinus).

A 26-year-old, female hyacinth macaw (Anodorhynchus hyacinthinus) was presented for ophthalmology consultation for a history of a chronic, nonhealing corneal ulcer of the right eye. On examination, a 5 × 4-mm axial, superficial corneal ulcer with loose epithelial edges was found. During multiple recheck examinations over 4 months, the ulcer was treated by debridement with a sterile cotton-tipped applicator, diamond burr debridement, diamond burr debridement with cyanoacrylate tissue adhesive, and grid keratotomy with cyanoacrylate tissue adhesive, all performed under anesthesia with eventual resolution of the corneal ulcer.

MANAGEMENT OF PODODERMATITIS WITH AN ORTHOTIC BOOT IN A SOUTHERN ISABELA GIANT TORTOISE (CHELONOIDIS VICINA).

A 62-yr-old male Southern Isabela giant tortoise (Chelonoidis vicina) had a 1-yr history of chronic, reoccurring pododermatitis on the palmar surface of the left forelimb. Aggressive wound management was instituted and included surgical debridement, vacuum-assisted closure, and orthotic boot support during healing. A custom fabricated, carbon fiber clamshell Charcot Restraint Orthotic Walker walking boot was utilized to reduce focal pressure over the wound during weight bearing and promote a more normal gait. Distal padding was used to distribute pressure on the palmar surface of the left forelimb, with a focal depression in the padding preventing pressure directly over the wound. The design and trim lines were adjusted to allow shoulder and elbow motion without impingement. The clamshell design allowed relatively easy removal for wound inspection and dressing changes. The wound ultimately resolved after 9 wk of management with the orthotic boot, with no reoccurrence over the next 3 yr.

ATTEMPTED SURGICAL CORRECTION OF A PERSISTENT RIGHT FOURTH AORTIC ARCH IN A JUVENILE ROTHSCHILD'S GIRAFFE (GIRAFFA CAMELOPARDALIS ROTHSCHILDI).

A 5-mo-old female Rothschild's giraffe ( Giraffa camelopardalis rothschildi) presented for regurgitation. Esophagoscopy at 24 wk of age revealed a markedly dilated cranial esophagus with a tight stricture at the level of the heart base consistent with a vascular ring anomaly. Surgical exploration confirmed persistent right fourth aortic arch with ductus originating from left subclavian artery at its junction with the aorta and left subclavian artery. The patent ductus arteriosus was surgically ligated. The procedure was complicated by limited surgical access and vascular friability resulting in uncontrollable hemorrhage, and the animal was euthanatized. The animal's large size and unique shape precluded preoperative examination by computed tomography. Surgical accessibility was poor because cranial retraction of the thoracic limb was limited. Histology revealed focal degeneration of the aorta and subclavian artery and muscular degeneration of the esophagus. Degeneration was attributed to local hypoxia from compression by the vascular structure as the animal grew.

PHARMACOKINETIC EVALUATION OF A LONG-ACTING FENTANYL SOLUTION AFTER TRANSDERMAL ADMINISTRATION IN HELMETED GUINEAFOWL (NUMIDA MELEAGRIS).

The objective of this study was to investigate the pharmacokinetics of a long-acting fentanyl solution in helmeted guineafowl ( Numida meleagris ) after transdermal administration. Twenty-one guineafowl received a single administration of 5 mg/kg of fentanyl transdermal solution. No adverse effects on behavior were appreciated. Plasma fentanyl concentrations were determined by liquid chromatography-mass spectrometry analysis of protein-precipitated samples. Mean maximum plasma concentration was 228.8 ng/ml at 4 hr. The mean plasma terminal half-life was 33.2 hr. At 168 hr the mean plasma concentration was 1.3 ng/ml. A single topical dose of 5 mg/kg appears to be safe for use in this species and maintained plasma concentrations above those reported to be analgesic in dogs for at least 7 days.

Evaluation of viruses and their association with ocular lesions in pinnipeds in rehabilitation.

OBJECTIVE: To assess whether corneal lesions in stranded pinnipeds were associated with viral infections, and to identify the potential pathogen(s) associated with the lesions. ANIMALS STUDIED: Twenty-nine California sea lions (Zalophus californianus), 18 northern elephant seals (Mirounga angustirostris), and 34 Pacific harbor seals (Phoca vitulina richardsii). PROCEDURE: DNA and RNA were extracted from ocular swabs, corneal tissue, and aqueous humor and screened for herpesvirus, adenovirus, poxvirus, and calicivirus families by PCR. RESULTS: The results indicated a high overall prevalence of viruses, with adenoviruses and herpesviruses detected in all three host species. Three novel adenoviruses (PhAdV-1, PhAdV-2, OtAdV-2) and two novel herpesviruses (PhHV-6, OtHV-4) were detected. There were no statistical differences in the prevalence of viral infection or coinfection among groups of individuals with or without corneal lesions, nor were lesion type, onset, or presence of concurrent disease significantly associated with a viral infection. CONCLUSIONS: The results suggested that viral presence in ocular tissues was common, not significantly associated with ocular disease and thus should not preclude release of an otherwise healthy animal. We could not confirm a correlation of virus presence with lesion due to the high percentage of virus-positive, clinically normal animals. This implied that seals and sea lions can have ocular tissues infected with several viruses without having readily evident associated lesions. This difficulty in correlating viral presence, particularly herpesviruses, with ocular lesions was also a common finding in studies with terrestrial species and highlighted the difficulty of confirming a virus as a primary pathogen in ocular lesions.