ABSTRACT
Physiological maintenance of electrolytes, hydrogen ions, carbon dioxide, and oxygen is essential for providing a cellular environment conducive to optimal cell function. The absolute and relative amounts of these substances and their interrelationships determine the osmolality, state of hydration, and membrane potentials of the animal. This chapter discusses the mechanisms resulting in changes in electrolyte and acid–base levels and the biochemical effects of these changes. Sample collection techniques and factors that influence the measurement of analytes are also addressed. Although laboratory animals are bred and housed in a uniform fashion, there are unexpected variations that can influence the electrolyte or blood gas balance. Knowledge of such conditions is essential for correct interpretation of data. Altitude, seasonal and diurnal changes, and breeding cycles need to be carefully assessed during the process of data interpretation; interspecies variation in effects should also be considered.
