Comparison of atlantoaxial and lumbosacral cerebrospinal fluid centesis techniques in South American camelids.

BACKGROUND: Iatrogenic blood contamination during cerebrospinal fluid (CSF) centesis is common, which can limit the diagnostic usefulness of the sample. A novel ultrasound-guided CSF collection technique is described in horses, by which CSF is obtained from the atlantoaxial (AA) space. HYPOTHESIS/OBJECTIVES: To compare ultrasound-guided AA centesis with lumbosacral (LS) centesis in South American camelids (SAC). The hypotheses were that AA centesis would yield samples with less blood contamination although being technically more challenging than LS centesis. ANIMALS: Eight clinically healthy adult SAC from a university-owned teaching herd. METHODS: Single-blinded, randomized, 4-way, 4-period crossover study in which 2 veterinarians each performed both centesis techniques on each animal once. Cytological sample analysis was performed, and the technical difficulty of sample acquisition was assessed. RESULTS: The CSF was collected successfully and without complications by either technique during all collection attempts. Aspects of technical difficulty and concentrations of CSF analytes did not vary significantly between techniques. Median total nucleated cell and red blood cell counts were 1/µL and 0.5/µL and 167.5/µL and 155/µL for AA and LS techniques, respectively. The median total protein concentration was 32.9 mg/dL and 38 mg/dL for AA and LS centeses. A median of 1 attempt was necessary for both centesis techniques and the median number of needle repositioning events was 1 for AA and 0 for LS. CONCLUSION AND CLINICAL IMPORTANCE: Depending on clinical circumstances, ultrasound-guided AA centesis appears to be an acceptable alternative to other techniques for collection of CSF from SAC.

Serosurvey for West Nile Virus Antibodies in Steller's Jays ( Cyanocitta stelleri ) Captured in Coastal California, USA.

West Nile virus (WNV) was first detected in New York in 1999 and, during its expansion across the continental US, southern Canada, and Mexico, members of the Corvidae (ravens, crows, magpies, and jays) were frequently infected and highly susceptible to the virus. As part of a behavioral study of Steller's Jays ( Cyanocitta stelleri ) conducted from 2011-14 in the coastal California counties of San Mateo and Santa Cruz, 380 Steller's Jays were captured and tested for antibodies to WNV. Using the wild bird immunoglobulin G enzyme linked immunoassay, we failed to detect antibodies to WNV, indicating either that there was no previous exposure to the virus or that exposed birds had died.

Characterization of West Nile viruses isolated from captive American Flamingoes (Phoenicopterus ruber) in Medellin, Colombia.

Serum samples from a total of 71 healthy captive birds belonging to 18 species were collected in July of 2008 in Medellin (Colombia) and tested for flaviviruses. Eighteen of 29 samples from American Flamingoes (Phoenicopterus ruber) were positive for West Nile virus (WNV) by reverse transcription-polymerase chain reaction. Selected positive samples were serially passaged and WNV was confirmed by immunofluorescence. Two isolates (524/08, 9835/08) were characterized in vitro and in vivo. Sequence analysis revealed WNV with 16 nucleotide substitutions resulting in six amino acid changes when compared with the NY99 strain. Colombian (COL) viruses were more closely related to Louisiana isolates from 2001. When compared with attenuated strains isolated from Texas, COL isolates differed in their plaque size and temperature sensitivity phenotype. The COL viruses were pathogenic in embryonated chicken eggs and Balb/c mice.