BACKGROUND Early recognition and management of acid-base, fluid, and electrolyte disorders are crucial for the maintenance of health and performance in equine athletes. OBJECTIVES To analyze changes in acid-base and electrolyte status associated with exercise during cross-country competitions at different levels using traditional and quantitative approaches. ANIMALS Thirty-eight eventing horses. METHODS Prospective observational study. Jugular venous blood samples were collected before and after the cross-country test of 25 international eventing competitions ranging from 2-star (formerly 1-star) to 5-star (formerly 4-star) level. Blood gas analysis was performed to determine pH, pCO2 , Na+ , Cl- , and K+ and calculate HCO3 - , tCO2 base excess (BEECF ), anion gap (AG), strong ion difference calculated from Na+ , K+ , Cl- , and lactate- (SID4 ), strong ion difference calculated from Na+ , K+ , and Cl- (SID3 ), strong ion gap (SIG), and total nonvolatile weak buffer concentration (Atot ). Postexercise acid-base imbalances, diagnosed on the basis of the traditional approach, and the simplified strong ion model were compared. RESULTS Significant decreases in pH, Cl- , SID4 , pCO2 , HCO3 - , tCO2 , and BEECF as well as increases in K+ , SID3 , AG, TP, and Atot were observed between pre- and postexercise samples. The changes in acid-base parameters were significantly affected by the competition level. Using the strong ion approach, a higher proportion of horses was diagnosed with postexercise metabolic acidosis. CONCLUSIONS AND CLINICAL IMPORTANCE Regarding the complex acid-base changes in horses competing at cross-country competitions, the quantitative approach provided a more detailed analysis of the different factors contributing to acid-base balance than did the traditional approach.

中文翻译：

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对参加2到5星越野赛的马匹进行酸碱和电解质失衡的传统和定量分析。

背景技术酸碱，液体和电解质紊乱的早期识别和管理对于维持马运动员的健康和表现至关重要。目的使用传统和定量方法分析越野比赛在不同水平上与运动相关的酸碱和电解质状态的变化。动物38匹三匹马。方法进行前瞻性观察研究。在从2星（以前为1星）到5星（以前为4星）级别的25个国际赛事的越野测试之前和之后，收集了颈静脉血样本。进行血气分析以确定pH，pCO2，Na +，Cl-和K +并计算HCO3-，tCO2碱过量（BEECF），阴离子间隙（AG），由Na +，K +，Cl-和乳酸计算的强离子差-（SID4），由Na +，K +和Cl-（SID3），强离子间隙（SIG）和总非易失性弱缓冲液浓度（Atot）计算得出的强离子差。比较了根据传统方法诊断出的运动后酸碱失衡和简化的强离子模型。结果运动前后样品之间的pH，Cl-，SID4，pCO2，HCO3-，tCO2和BEECF显着降低，并且K +，SID3，AG，TP和Atot升高。酸碱参数的变化受到竞争水平的显着影响。使用强离子方法，可以诊断出较高比例的马运动后代谢性酸中毒。结论和临床意义关于越野比赛中赛马的复杂酸碱变化，