Technical note: using calcium carbonate as an osmolar control treatment for acid-base studies in horses.

This research study evaluates the effectiveness of using calcium carbonate as an osmolar control treatment in horses during acid-base studies, specifically when horses are receiving alkalizing compounds like sodium bicarbonate.

Study Methodology

• The study involved six mares which were intubated through the nose with isomolar quantities of either sodium or calcium, presented as sodium bicarbonate or calcium carbonate. Water was also used during three different treatment periods.
• The researchers used two carbonic acid salts in this study: sodium bicarbonate and calcium carbonate. The sodium bicarbonate was mixed with distilled water and given to the horses in doses of 500 mg/kg. The calcium carbonate was similarly mixed with distilled water, but in doses of 595mg/kg. These mixtures were intended to achieve isoosmolar treatments, meaning they have the same osmotic concentration.
• As controls, the mares were also treated with four liters of distilled water. This served as a negative control, where no active treatment was given.
• The researchers performed blood sampling from the jugular vein before the intubation process and then at hourly intervals for a total of six hours after the intubation.

Results and Data Analysis

• The blood samples collected were analyzed for the levels of serum electrolytes Na+ (sodium) and K+ (potassium), as well as blood pH, and bicarbonate ions (HCO3-).
• The data indicated that the sodium bicarbonate treatment resulted in an increase in blood pH and HCO3- levels (P < 0.01) above both the water and calcium carbonate treatments. This translates to a statistically significant effect in maintaining the acid-base balance when compared to the other treatments.
• No significant differences (P > 0.05) were noticed between the effects of water and calcium carbonate treatments, suggesting they had similar effects on the acid-base balance of the horses.

Conclusion

• Based on the results, the researchers proposed that calcium carbonate could be utilized as a suitable osmolar control treatment during studies investigating the effects of treatments on the acid-base status of horses. This is due to its similar effects with water (the control treatment), suggesting that it does not significantly affect the acid-base balance.