Constable Peter, Grünberg Walter, Staufenbiel Rudolf, Stämpfli Henry R
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA.
J Am Vet Med Assoc. 2013 Mar 15;242(6):826-35. doi: 10.2460/javma.242.6.826.
To identify potential mechanisms for hypokalemia in dairy cows with left-displaced abomasum (LDA), right-displaced abomasum (RDA), or abomasal volvulus (AV).
Retrospective analysis of clinicopathologic data from 2 convenience samples of cows.
112 lactating dairy cows with AV (group 1); 1,332 lactating dairy cows (group 2) with LDA (n = 1,160) or RDA or AV (172).
Data were analyzed via Spearman ρ and multivariate stepwise regression.
78 of 112 (70%) group 1 cows were hypokalemic (mean serum potassium concentration, 3.5 mEq/L; reference range, 3.9 to 5.8 mEq/L). For group 1 cows, serum chloride concentration had the strongest positive association with serum potassium concentration, and serum potassium concentration was negatively associated with plasma bicarbonate and serum glucose, creatinine, and urea concentrations. Six hundred thirty-six of 1,160 (55%) of group 2 cows with LDA were hypokalemic (mean serum potassium concentration, 3.7 mEq/L). Ninety-two of 172 (53%) group 2 cows with RDA or AV were hypokalemic (mean serum potassium concentration, 3.8 mEq/L). For group 2 cows, serum chloride concentration had the strongest positive association with serum potassium concentration, and serum potassium concentration was negatively associated with indices of feed intake (serum bilirubin concentration) and hydration status.
Results suggested hypokalemia was associated with hypochloremia, alkalemia, low feed intake with high amount of milk produced, hypovolemia, and hyperglycemia in lactating dairy cows. Treatment of hypokalemia should include surgical correction of abomasal displacement, increased dietary potassium intake via dietary dry matter intake or oral administration of KCl, and correction of hypochloremia, alkalemia, metabolic alkalosis, and dehydration.
确定左方变位真胃（LDA）、右方变位真胃（RDA）或真胃扭转（AV）的奶牛发生低钾血症的潜在机制。
对来自2个奶牛便利样本的临床病理数据进行回顾性分析。
112头患有AV的泌乳奶牛（第1组）；1332头患有LDA（n = 1160）或RDA或AV（172头）的泌乳奶牛（第2组）。
通过Spearman ρ和多元逐步回归分析数据。
第1组的112头奶牛中有78头（70%）发生低钾血症（血清钾浓度均值为3.5 mEq/L；参考范围为3.9至5.8 mEq/L）。对于第1组奶牛，血清氯浓度与血清钾浓度的正相关性最强，血清钾浓度与血浆碳酸氢盐、血清葡萄糖、肌酐和尿素浓度呈负相关。第2组1160头患有LDA的奶牛中有636头（55%）发生低钾血症（血清钾浓度均值为3.7 mEq/L）。第2组172头患有RDA或AV的奶牛中有92头（53%）发生低钾血症（血清钾浓度均值为3.8 mEq/L）。对于第2组奶牛，血清氯浓度与血清钾浓度的正相关性最强，血清钾浓度与采食量指标（血清胆红素浓度）和水合状态呈负相关。
结果表明，泌乳奶牛的低钾血症与低氯血症、碱血症、产奶量高导致采食量低、血容量不足和高血糖有关。低钾血症的治疗应包括对真胃移位进行手术矫正，通过增加日粮干物质采食量或口服氯化钾来增加日粮钾摄入量，以及纠正低氯血症、碱血症、代谢性碱中毒和脱水。
