Effect of orally administered sodium bicarbonate on caecal pH.

Abstract

REASONS FOR PERFORMING STUDY: Caecal acidosis is a central event in the metabolic cascade that occurs following grain overload. Buffering the caecal acidosis by enterally administered sodium bicarbonate (NaHCO3 ) may be beneficial to affected horses. OBJECTIVES: To determine the effect and duration of enterally administered NaHCO3 on caecal pH in healthy horses. STUDY DESIGN: Experimental study using horses with caecal cannulas. METHODS: Nine horses had been previously fitted with a caecal cannula. Six horses received 1.0 g/kg bwt NaHCO3 and 3 control horses were given 3 l of water via nasogastric tube. Clinical parameters, water consumption, venous blood gases, caecal pH, faecal pH and faecal water content were measured at 6 h intervals over a 36 h study period. RESULTS: Horses that received enterally administered NaHCO3 had significantly increased caecal pH that lasted the duration of the study. Treated horses increased their water intake, and developed metabolic alkalaemia, significantly increased plasma sodium concentrations and significantly decreased plasma potassium concentrations. CONCLUSIONS: Enterally administered NaHCO3 may be beneficial in buffering caecal acidosis.