Investigations on D-lactate metabolism in neonatal calves with and without diarrhea

尽管有众所周知的预防策略，犊牛新生儿腹泻仍然是全世界所有牛生产系统中死亡和经济损失的主要来源。受感染动物的临床后果不仅源于体液过多流失导致的脱水，还源于代谢性酸中毒的发生。由于胃肠道细菌发酵过程导致血d -乳酸浓度升高，在代谢性酸中毒的发生中起着重要作用。它们也对相关的临床表现产生重大影响，其特征是严重抑郁、神经异常和站立能力受损。本研究的目的是评估实验诱导的强离子（代谢性）酸中毒是否会影响新生小牛的d -乳酸代谢。该项目的另一个目的是评估不同剂量的碳酸氢钠和乳酸林格氏液（含有D-乳酸和l -乳酸的外消旋混合物）补液如何影响自然获得性腹泻的酸性犊牛D-乳酸清除率。本研究项目的结果有望改善对新生儿腹泻小牛d -乳酸代谢的了解，并可能对这些动物的治疗建议和静脉输液方案的优化产生影响。

In spite of well-known preventive strategies, neonatal diarrhea in calves remains worldwide a leading source of mortality and economic losses in all bovine production systems. Clinical consequences in affected animals do not only arise from dehydration due to excessive fluid losses, but also from the occurrence of metabolic acidosis. Increased blood D-lactate concentrations as a result of bacterial fermentation processes in the gastrointestinal tract are playing a major role in the development of metabolic acidosis. They also have a major impact on the associated clinical picture which is characterized by severe depression, neurological abnormalities, and impairments of the ability to stand.The aim of the intended research project described here is to assess whether an experimentally induced strong ion (metabolic) acidosis affects D-lactate metabolism in neonatal calves. A further aim of this project is to assess how different dosages of sodium bicarbonate and rehydration with lactated Ringer's solution (containing a racemic mixture of D- and L-lactate) affect D-lactate clearance in acidotic calves with naturally acquired diarrhea. Results of this research project are expected to result in an improved understanding of D-lactate metabolism in neonatal diarrheic calves and will likely have an impact on treatment recommendations and optimization of intravenous fluid protocols for these animals.