Fatal sodium intoxication can occur in many species, including cattle, and postmortem confirmation often includes brain sodium concentration determination. Published information regarding brain sodium distribution in cattle was not found in a literature review. Our study was designed to determine whether sodium is uniformly distributed throughout the bovine brain. Eight whole bovine brains were collected from adult cattle with no neurologic signs or history suggestive of sodium intoxication, and with a non-neurologic cause of death diagnosed on gross examination. Brains were divided mid-sagittally. One hemisphere of each brain was homogenized. Subsamples were obtained from the remaining hemisphere (rostral, caudal, and dorsal cerebral cortices; brainstem, thalamus, and cerebellum). Sodium concentrations of regions and homogenates were measured by inductively coupled plasma–mass spectrometry. Data were analyzed using repeated measures ANOVA with a pairwise post-test to compare mean sodium concentration of each region to mean homogenate sodium concentration. Brain sodium was not uniformly distributed; sodium concentrations in different regions of the same brain varied somewhat unpredictably. Homogenization of an entire brain hemisphere appears to be the ideal method of sample preparation to ensure accurate brain sodium concentration measurement in adult cattle.

许多物种都可能发生致命的钠中毒，包括牛，死后确认通常包括脑钠浓度测定。文献综述中未发现有关牛脑钠分布的已发表信息。我们的研究旨在确定钠是否均匀分布在整个牛脑中。从成年牛身上收集了 8 个完整的牛脑，这些牛没有神经系统体征或钠中毒史，肉眼检查诊断出非神经系统死亡原因。大脑在矢状面中间分开。每个大脑的一个半球被均质化。从剩余的半球（头侧、尾侧和背侧大脑皮层；脑干、丘脑和小脑）获得子样本。通过电感耦合等离子体质谱法测量区域和匀浆的钠浓度。使用重复测量方差分析和成对后检验分析数据，以比较每个区域的平均钠浓度与平均匀浆钠浓度。脑钠分布不均；同一大脑不同区域的钠浓度变化有些出乎意料。整个大脑半球的均质化似乎是确保准确测量成年牛脑钠浓度的理想样品制备方法。同一大脑不同区域的钠浓度变化有些出乎意料。整个大脑半球的均质化似乎是确保准确测量成年牛脑钠浓度的理想样品制备方法。同一大脑不同区域的钠浓度变化有些出乎意料。整个大脑半球的均质化似乎是确保准确测量成年牛脑钠浓度的理想样品制备方法。