Survival associated with cerebrospinal fluid analysis in downer adult dairy cows: A retrospective study (2006-2014).

BACKGROUND

Threshold values for total nucleated cell count (TNCC) and protein concentration in cerebrospinal fluid (CSF) of downer dairy cows suggestive of a spinal cord lesion were recently published.

OBJECTIVES

Determine short- and long-term survival of downer cows that underwent CSF analysis using the reported threshold values. Evaluate the prognostic value of these threshold values to predict short- and long-term survival.

ANIMALS

Two hundred and fourteen downer adult dairy cows that underwent CSF analysis during hospitalization at the Centre Hospitalier Universitaire Vétérinaire (CHUV) of the Université de Montréal.

METHODS

Retrospective study. Medical records of downer adult dairy cows presented to the hospital between January 2006 and October 2014 for which CSF analysis results were available were studied. Short-term (discharge from hospital) and long-term (completion of lactation) survival were determined and compared in accordance with CSF TNCC and protein concentration, using a Chi-square test.

RESULTS

Cows with CSF TNCC and/or protein concentration above the threshold values had a significantly lower short-term survival rate (P = .02). The odds of nonsurvival of cows with one or both CSF values above the threshold values was 2.16 times higher than the odds for cows with values under the threshold values. CSF TNCC >4.5 cells/μL had sensitivity and specificity of 17.3% (95% CI: 10.7%-25.7%) and 92.3% (95% CI: 85.4%-96.6%), respectively, for predicting short-term nonsurvival. CSF protein concentration >0.39 g/L had sensitivity and specificity of 20.9% (95% CI: 13.7%-29.7%) and 91.4% (95% CI: 84.2%-96.0%), respectively.

CONCLUSIONS

CSF analysis above threshold values used in this study is associated with increased odds of short-term nonsurvival.