Acid-base disorders in calves with chronic diarrhea

Area of Science:

• Veterinary Medicine
• Biochemistry
• Animal Physiology

Background:

• Chronic diarrhea in calves is often caused by mixed infections (viral, bacterial, Cryptosporidium parvum).
• Acid-base balance disorders are common in affected calves, complicating their management.
• Accurate assessment of acid-base status is crucial for effective treatment strategies.

Purpose of the Study:

• To analyze acid-base balance disorders in calves with chronic diarrhea.
• To compare the diagnostic utility of the classic Henderson-Hasselbalch model and the strong ion approach (Steward model).
• To investigate the impact of hypoalbuminemia on acid-base status in diarrheic calves.

Main Methods:

• Study included 36 calves (14-21 days old) divided into control, compensated acid-base imbalance, and compensated acid-base disorders with hypoalbuminemia groups.
• Measured plasma electrolytes (Na+, K+, Cl-, Ca2+, Mg2+, P), albumin, and lactate.
• Analyzed acid-base balance using both the Henderson-Hasselbalch model (pH, pCO2, HCO3-, BE, anion gap) and the Steward model (SID, A(Tot), SIG).

Main Results:

• Calves with chronic diarrhea showed significantly higher HCO3-, BE, and pCO2 compared to controls.
• Hypoalbuminemic calves (Group III) exhibited lower albumin, Cl-, Mg2+, P, and higher anion gap.
• Group III also showed significantly higher SID3, SID7, and SIG, with lower A(Tot) compared to other groups.
• Excellent correlation found between corrected anion gap (AGcorr) and SID3, SID7, SIG.

Conclusions:

• Chronic diarrhea induces complex water-electrolyte disturbances in calves.
• The Steward strong ion approach provides a more comprehensive characterization of acid-base disturbances than the classic model.
• The classic model has limitations and is not recommended when serum albumin or phosphate levels are significantly abnormal.