Department of Veterinary Internal Medicine, College of Veterinary Medicine, Jeonbuk National University, 79 Gobong-ro, Iksan, 54596, Republic of Korea.
Hanwoo (Korean Indigenous Cattle) Genetic Improvement Center, National Agricultural Cooperative Federation, Seosan, Republic of Korea.
BMC Vet Res. 2024 Aug 20;20(1):373. doi: 10.1186/s12917-024-04235-0.
Calf diarrhea leads to high mortality rates and decreases in growth and productivity, causing negative effects on the livestock industry. Lactate is closely associated with metabolic acidosis in diarrheic calves. However, there have been no reports on lactate concentrations in Korean indigenous (Hanwoo) calves, especially those with diarrhea. This study aimed to determine the reference range of L-lactate and D-lactate concentrations in Hanwoo calves and to better understand the utility of lactate as predictive factors for acidemia in diarrheic calves.
L-lactate and D-lactate concentrations were measured in healthy (n = 44) and diarrheic (n = 93) calves, and blood gas analysis was performed on diarrheic calves. The reference range in healthy calves was 0.2-2.25 mmol/L for L-lactate and 0.42-1.38 mmol/L for D-lactate. Diarrheic calves had higher concentrations of L-lactate and D-lactate than healthy calves. In diarrheic calves, L-lactate and D-lactate each had weak negative correlation with pH (r = - 0.31 and r = - 0.35). In diarrheic calves with hyper-L-lactatemia, the combined concentrations of L-lactate and D-lactate had moderate correlation with pH (r = - 0.51) and anion gap (r = 0.55). Receiver operating characteristic analysis showed D-lactate had fair predictive performance (AUC = 0.74) for severe acidemia, with an optimal cut-off value of > 1.43 mmol/L. The combined concentrations of L-lactate and D-lactate showed fair predictive performance for predicting acidemia (AUC = 0.74) and severe acidemia (AUC = 0.72), with cut-off values of > 6.05 mmol/L and > 5.95 mmol/L.
The determined reference ranges for L-lactate and D-lactate in Hanwoo calves enable the identification of hyper-L-lactatemia and hyper-D-lactatemia. Diarrheic calves exhibited increased lactate concentrations correlated with acid-base parameters. While the concentrations of L-lactate and D-lactate have limitations as single diagnostic biomarkers for predicting acidemia or severe acidemia, their measurement remains important, and L-lactate has the advantage of being measurable at the point-of-care. Assessing lactate concentrations should be considered by clinicians, especially when used alongside other clinical indicators and diagnostic tests. This approach can improve calf diarrhea management, contributing positively to animal welfare and providing economic benefits to farms.
犊牛腹泻会导致高死亡率和生长及生产性能下降，给畜牧业带来负面影响。乳酸与腹泻犊牛的代谢性酸中毒密切相关。然而，目前还没有关于韩国本土（韩牛）犊牛乳酸浓度的报告，特别是腹泻犊牛的乳酸浓度报告。本研究旨在确定韩牛犊牛乳酸和 D-乳酸的参考范围，并更好地了解乳酸作为预测腹泻犊牛酸中毒的指标的作用。
在健康（n=44）和腹泻（n=93）犊牛中测量了 L-乳酸和 D-乳酸的浓度，并对腹泻犊牛进行了血气分析。健康犊牛的 L-乳酸参考范围为 0.2-2.25mmol/L，D-乳酸参考范围为 0.42-1.38mmol/L。腹泻犊牛的 L-乳酸和 D-乳酸浓度均高于健康犊牛。在腹泻犊牛中，L-乳酸和 D-乳酸与 pH 值均呈弱负相关（r=-0.31 和 r=-0.35）。在高乳酸血症的腹泻犊牛中，L-乳酸和 D-乳酸的联合浓度与 pH 值（r=-0.51）和阴离子间隙（r=0.55）呈中度相关。受试者工作特征分析显示，D-乳酸对严重酸中毒具有较好的预测性能（AUC=0.74），最佳截断值>1.43mmol/L。L-乳酸和 D-乳酸联合浓度对预测酸中毒（AUC=0.74）和严重酸中毒（AUC=0.72）具有较好的预测性能，截断值分别为>6.05mmol/L 和>5.95mmol/L。
本研究确定了韩牛犊牛 L-乳酸和 D-乳酸的参考范围，可用于识别高乳酸血症和高 D-乳酸血症。腹泻犊牛的乳酸浓度升高，与酸碱参数相关。虽然 L-乳酸和 D-乳酸的浓度作为预测酸中毒或严重酸中毒的单一诊断生物标志物存在局限性，但它们的测量仍然很重要，并且 L-乳酸具有可在床边测量的优势。临床医生应考虑评估乳酸浓度，特别是当与其他临床指标和诊断测试一起使用时。这种方法可以改善犊牛腹泻的管理，对动物福利产生积极影响，并为农场带来经济效益。
