Clinic for Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Koenigsweg 65, 14163 Berlin, Germany.
J Dairy Sci. 2012 Nov;95(11):6449-56. doi: 10.3168/jds.2012-5329. Epub 2012 Sep 7.
In cattle, blood lactate was measured in various conditions such as parturition and dystocia. To our knowledge, to date, no handheld device has been validated for the use in cows and only one handheld device was validated for the use in calves. When determining plasma lactate concentrations blood samples have to be processed carefully. Sodium fluoride was recommended to inhibit glycolysis and to stabilize plasma lactate concentrations during transport. However, its effect on measurements conducted with electrochemical meters has not been studied. The objectives of 3 experiments were to study factors influencing measures of L-lactate in dairy cows (e.g., different anticoagulants, different methods) and to validate a handheld device (Lactate Scout, SensLab GmbH, Leipzig, Germany) to determine L-lactate concentration in dairy cows and calves. In a first approach, blood samples from 49 cows were analyzed by 2 different laboratories. Measures of L-lactate concentration were correlated between the different laboratories in both lithium heparin plasma (r=0.98) and sodium fluoride plasma (r=0.99). In a second approach, these samples were analyzed using 3 methods [Lactate Scout, Biosen C_line (EKF Diagnostics GmbH, Barleben, Germany), and commercial laboratory]. Concentrations of L-lactate measured in lithium heparin did not differ when analyzed with the Lactate Scout (0.99±0.35 mmol/L), the Biosen C_line (0.81±0.26 mmol/L), or the laboratory (1.0±0.36 mmol/L). Concentrations of L-lactate measured in sodium fluoride, however, were higher when analyzed with the Lactate Scout (1.85±0.66 mmol/L) compared with those measured with the Biosen C_line (0.92±0.37 mmol/L) and by the commercial laboratory (0.72±0.45 mmol/L). In the second and third experiments, blood samples from 173 cows and 106 calves were analyzed using the 3 methods (Lactate Scout, Biosen C_line, and commercial laboratory). L-Lactate concentrations measured with the 3 methods were correlated (cows: Lactate Scout vs. Biosen C_line: r=0.97, Lactate Scout vs. laboratory 1: r=0.98, Biosen C_line vs. laboratory 1: r=0.99; calves: Lactate Scout vs. Biosen C_line: r=0.97, Lactate Scout vs. laboratory 1: r=0.98, Biosen C_line vs. laboratory 1: r=0.99). In conclusion, Lactate Scout and Biosen C_line measure blood L-lactate concentrations reliably compared with a commercial laboratory as the reference method in dairy cows and calves. However, attention needs to be paid to the choice of anticoagulant used in sample collection.
在牛中，已经在分娩和难产等各种情况下测量了血液中的乳酸。据我们所知，迄今为止，还没有经过验证可用于牛的手持式设备，只有一种手持式设备经过验证可用于小牛。在确定血浆乳酸浓度时，必须小心处理血液样本。推荐使用氟化钠来抑制糖酵解并在运输过程中稳定血浆乳酸浓度。然而，其对电化学计测量的影响尚未得到研究。三个实验的目的是研究影响奶牛（例如，不同的抗凝剂，不同的方法）中 L-乳酸测量的因素，并验证一种手持式设备（Lactate Scout，SensLab GmbH，莱比锡，德国），以确定奶牛和小牛中的 L-乳酸浓度。在第一种方法中，通过两个不同的实验室分析了 49 头奶牛的血液样本。锂肝素血浆（r=0.98）和氟化钠血浆（r=0.99）中不同实验室之间的 L-乳酸浓度测量结果相关。在第二种方法中，使用 3 种方法[Lactate Scout，Biosen C_line（EKF Diagnostics GmbH，Barleben，德国）和商业实验室]分析了这些样品。用锂肝素分析时，用 Lactate Scout（0.99±0.35mmol/L），Biosen C_line（0.81±0.26mmol/L）或实验室（1.0±0.36mmol/L）测量的 L-乳酸浓度没有差异。但是，用 Lactate Scout 分析时，用氟化钠测量的 L-乳酸浓度（1.85±0.66mmol/L）高于用 Biosen C_line（0.92±0.37mmol/L）和商业实验室（0.72±0.45mmol/L）测量的浓度。在第二和第三个实验中，使用 3 种方法（Lactate Scout，Biosen C_line 和商业实验室）分析了 173 头奶牛和 106 头小牛的血液样本。用 3 种方法测量的 L-乳酸浓度相关（奶牛：Lactate Scout 与 Biosen C_line：r=0.97，Lactate Scout 与实验室 1：r=0.98，Biosen C_line 与实验室 1：r=0.99；小牛：Lactate Scout 与 Biosen C_line：r=0.97，Lactate Scout 与实验室 1：r=0.98，Biosen C_line 与实验室 1：r=0.99）。总之，与商业实验室作为参考方法相比，Lactate Scout 和 Biosen C_line 可可靠地测量奶牛和小牛血液中的 L-乳酸浓度。但是，需要注意在样本采集过程中选择抗凝剂。
