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  • Author or Editor: Cheryl L. Chrisman x
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Objective—To establish reference values for electrodiagnostic evaluation of peripheral nerve function in birds.

Animals—6 rheas and 6 barred owls.

Procedure—Birds were anesthetized with propofol or isoflurane in oxygen. Using a computer-based electromyograph system and needle electrodes for stimulation and recording, electromyography (EMG) was performed on the pectoral, biceps brachialis, and gastrocnemius muscles, and evoked EMG was performed on the tibial and ulnar nerves. Motor nerve conduction velocity (MNCV) was calculated. Repetitive stimulation was performed on these 2 nerves. Late F waves were recorded for each nerve, when possible.

Results—Activity was evident during insertion of the electrodes, but muscles tested were electrically quiescent after spontaneous EMG. Motor nerve conduction velocity was faster in the tibial nerve than ulnar nerve but did not differ significantly between species. Mean ± SEM MNCV was 132.3 ±± 7.8 m/s for the tibial nerve and 59.7 ± 7.8 m/s for the ulnar nerve. A significant difference was not observed in responses at the fourth or ninth stimulation during repetitive stimulation. Subsequent to the initial stimulation, amplitudes were ± 22.7% of the initial motor potential amplitude. Recorded F waves were inconsistent, which may have been associated with technique.

Conclusions and Clinical Relevance—Reference range (mean ± 2 SEM) for MNCV was 34.1 to 75.3 m/s for the ulnar nerve and 116.7 to 147.9 m/s for the tibial nerve in barred owls and rheas. After repetitive stimulation, motor potential amplitudes may be ± 22.7% of the initial amplitude response. (Am J Vet Res 2000;61:469–472)

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in American Journal of Veterinary Research


Objective—To determine clinical signs, results of diagnostic testing, underlying cause, and outcome in cats with seizures.

Design—Retrospective study.

Animals—17 cats with seizures.

Procedure—Only those cats in which an underlying metabolic abnormality causing the seizures had been identified, diagnostic imaging of the brain and CSF analysis had been done, or a necropsy had been performed were included. Seizures were classified as being a result of metabolic disease, symptomatic epilepsy (ie, epilepsy resulting from a structural lesion of the brain), or probably symptomatic epilepsy (ie, epilepsy without any extracranial or identifiable intracranial disease that is not suspected to be genetic in origin).

Results—3 cats had seizures associated with an underlying metabolic disease (hepatic encephalopathy), 7 had symptomatic epilepsy (3 with neoplasia and 4 with meningoencephalitis), and 7 had probably symptomatic epilepsy. Six of the 7 cats with symptomatic epilepsy died or were euthanatized within 3 months after the diagnosis was made, whereas 6 of the 7 cats with probably symptomatic epilepsy survived for at least 12 months after the diagnosis was made.

Conclusions and Clinical Relevance—Results suggest that cats with probably symptomatic epilepsy may have a good long-term prognosis. (J Am Vet Med Assoc 2004;225:1723–1726)

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in Journal of the American Veterinary Medical Association


Objective—To determine whether plasma concentrations of benzodiazepines (BDZ) in dogs following intranasal (IN) administration of diazepam are comparable to concentrations following IV administration.

Animals—6 (4 male, 2 female) healthy adult Greyhounds.

Procedure—Dogs were randomly assigned to 2 groups of 3 dogs in a crossover design. Diazepam (0.5 mg/kg of body weight) was administered intravenously to dogs in group 1 and intranasally to dogs in group 2. Blood was collected from the jugular vein of each dog into tubes containing lithium heparin before and 3, 6, 9, 12, 15, 20, 30, 60, 120, 240, and 480 minutes following diazepam administration. After a 4-day washout period, dogs in group 1 received diazepam intranasally, dogs in group 2 received diazepam intravenously, and blood was again collected. Plasma concentration of BDZ was determined by use of a fluorescence polarization immunoassay.

Results—Mean (± SD) peak plasma concentration of BDZ following IV administration (1316 ± 216 µg/L) was greater than that following IN administration (448 ± 41 µg/L). Time to peak concentration was ≤ 3 minutes following IV administration and 4.5 ± 1.5 minutes following IN administration. Mean bioavailability of BDZ following IN administration was 80 ± 9%.

Conclusions and Clinical Relevance—Diazepam is rapidly and efficiently absorbed following IN administration of the parenteral formulation. Plasma concentrations match or exceed the suggested therapeutic concentration (300 µg/L). Intranasal administration of diazepam may be useful for treatment of seizures in dogs by owners or when intravenous access is not readily available. (Am J Vet Res 2000;61:651–654)

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in American Journal of Veterinary Research


Objective—To determine the protein and cellular composition of CSF in healthy adult ferrets.

Animals—42 clinically normal adult ferrets.

Procedure—CSF samples were collected from the cerebellomedullary cistern of anesthetized ferrets by use of disposable 25-gauge, 1.6-cm-long hypodermic needles. Samples were processed within 20 minutes after collection. The number of WBCs and RBCs per microliter of CSF was counted by use of a hemacytometer. The total protein concentration was determined by use of an automated chemistry analyzer.

Results—Total WBC counts (range, 0 to 8 cells/µL; mean, 1.59 cells/µL) in CSF of ferrets were similar to reference range values obtained for CSF from other species. Twenty-seven CSF samples had < 100 RBCs/µL (mean, 20.3 RBCs/µL). A small but significant effect of blood contamination on WBC counts was found between the 27 CSF samples with < 100 RBCs/µL and the remaining samples. Protein concentrations in CSF of ferrets (range, 28.0 to 68.0 mg/dL; mean, 31.4 mg/dL) were higher than has been reported for the CSF of dogs and cats. A significant effect of blood contamination on the CSF protein concentration was not found.

Conclusions and Clinical Relevance— We have established reference range values for WBC counts and protein concentrations in CSF from healthy adult ferrets that may be useful in the clinical investigation of CNS disease. Results of our study indicate that the WBC count is significantly affected by blood contamination of the CSF sample. (Am J Vet Res 2004;65:758–760)

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in American Journal of Veterinary Research


To determine whether neurologic examination techniques established for use on dogs and cats could be adapted for use on sea turtles.


Prospective controlled observational study.


4 healthy Green Turtles (Chelonia mydas), 1 healthy Kemp's ridley sea turtle (Lepidochelys kempi), and 6 Green Turtles suspected to have neurologic abnormalities.


Neurologic examinations were performed while sea turtles were in and out of the water and in ventral and dorsal recumbency. Mentation, general activity, head and body posture, movement and coordination, thoracic and pelvic limb movement, strength and muscle tone, and tail movement were observed. Thoracic and pelvic limb flexor reflexes and nociception, righting response, cranial nerve reflexes, clasp and cloacal reflexes, and neck, dorsal scute, cloacal, and tail nociception were tested.


Results of neurologic evaluations were consistent for healthy sea turtles. Sea turtles suspected to have neurologic abnormalities had abnormal results.

Clinical Implications

Many of the neurologic examination techniques used to evaluate dogs and cats can be adapted and used to evaluate sea turtles. A standardized neurologic examination should result in an accurate assessment of neurologic function in impaired sea turtles and should help in evaluating effects of rehabilitation efforts and suitability for return to their natural environment. (J Am Vet Med Assoc 1997;211:1043–1047)

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in Journal of the American Veterinary Medical Association