Correlation between L-Lactate Concentrations in Beef Cattle, Obtained Using a Hand-Held Lactate Analyzer and a Lactate Assay Colorimetric Kit

Abstract

Lactate is a product of anaerobic glycolysis, used in animal research as an indicator of muscle fatigue. Therefore, it has been used as an indicator of cattle response to long distance transportation. The aim of this study was to assess the relationship of L-lactate concentrations measured using a Lactate Scout+ analyzer and a traditional lactate assay colorimetric kit. Blood samples were collected by venipuncture from 96 steers (Black or Red Angus × Hereford/Simmental and Black or Red Angus × Charolais; 247 ± 38.2 kg BW) prior to loading (LO1) and after 36 h of transport, and prior to reloading and after an additional 4 h of road transportation, and on d 1, 2, 3, 5, 14, and 28 after transport. The Lactate Scout+ analyzer strip was dipped in blood at the time of sampling, while blood samples were collected into sodium fluoride tubes for use in the colorimetric analysis. Pearson correlations were calculated to assess the strength of the relationship between the experimental methods for the quantification of L-lactate concentrations. The magnitude and direction of the correlation, and the level of statistical significance varied over the observed time points, ranging from r = −0.03 (p = 0.75; LO1) to r = 0.75 (p < 0.0001; d 3). The correlation for the pooled data was weak but statistically significant (r = 0.33, p < 0.0001). Based on the low magnitude of the correlation due to variability across sampling time points in this study, the Lactate Scout+ analyzer is not a suitable alternative to a lab-based assay (considered the gold standard) for measuring L-lactate in transported cattle.

Physicochemical Evaluations of Diets, Rumen Fluid, Blood and Faeces of Beef Cattle under Two Different Feedlot Systems

“…The reference value of healthy cattle is 0.60 up to 2.2 mmol/L [ 33 ]. According Meléndez et al [ 34 ] the values obtained with handheld lactate meters are not comparable to concentrations obtained with a bench type approach used in the laboratory. This may explain why healthy cattle raised on pastures in the current work had values above those considered normal ( Table 8 ).…”

L-Lactate Electrochemical Biosensor Based on an Integrated Supramolecular Architecture of Multiwalled Carbon Nanotubes Functionalized with Avidin and a Recombinant Biotinylated Lactate Oxidase

“…L-Lactate oxidase (LOx) (EC 1.1.3.2) is a member of the family of flavoproteins and catalyzes the oxidation of L-lactate into pyruvate and generates hydrogen peroxide in the presence of oxygen [23,24]. LOx can be obtained from several bacterial sources and is used as a biocatalyst to develop enzyme-based biosensors and colorimetric in vitro tests for L-lactate detection [21,22,25,26].…”