D-Lactic acidosis in calves

Area of Science:

• Veterinary Medicine
• Ruminant Health
• Neonatal Calf Care

Background:

• Metabolic acidosis is a known complication of neonatal calf diarrhea.
• Previously, bicarbonate loss was considered the main cause of acidosis and associated neurological signs.
• Acidosis-without-dehydration syndrome and ruminal drinking were also implicated.

Purpose of the Study:

• To review the current understanding of d-lactic acidosis in neonatal calves.
• To highlight the shift in understanding from general metabolic acidosis to specific d-lactic acidosis.
• To differentiate the causes of neurological signs in diarrheic calves.

Main Methods:

• Literature review of recent research on calf metabolic acidosis and d-lactate.
• Analysis of evidence linking d-lactate to clinical signs in neonatal calf diarrhea.
• Synthesis of information on the pathogenesis of d-lactic acidosis in calves.

Main Results:

• D-lactic acidosis is a more common cause of metabolic disturbance in neonatal calf diarrhea than previously thought.
• Bacterial fermentation of undigested substrate in the large intestine leads to D-lactate accumulation.
• Elevated blood D-lactate levels are now recognized as the cause of many neurological signs previously attributed to general acidosis.

Conclusions:

• D-lactic acidosis is a critical consideration in neonatal calf diarrhea, often underlying neurological impairment.
• Understanding the source of D-lactate is crucial for accurate diagnosis and treatment.
• This review provides an updated perspective on d-lactic acidosis in calves.