The glutaraldehyde test and its use in dairy cattle

During a physical examination of cattle, it is often difficult to evaluate inflammatory processes, particularly in cases where the inflammation occurs in deeper regions. The glutaraldehyde test (GT), carried out using a sample of whole blood, allows the visual and semiquantitative identification of an inflammatory process in cattle. Considering that there are few biochemical tests that can be used in the field, the objective of this study was to verify the efficacy of the GT in detecting and predicting mild and severe inflammatory processes in bovine species, classified according to a physical examination, and in the presence of different diseases or lesions. The GT was used in conjunction with a physical examination in 176 cows over 12 months of age, with additional laboratory evaluations of packed cell volume, total protein, albumin, globulin, and fibrinogen. Using a cutoff point at 3 minutes of coagulation, the GT showed a sensitivity of 35.1%, specificity of 94.1%, positive predictive value of 74.1%, and negative predictive value of 75.2%. The GT correctly detected the most severe inflammatory processes under the field conditions of this study. The GT is a diagnostic aid that can be used as a fast and simple screening test during the physical examination of cattle.