• Open Access

Hypocalcemia and Hypovitaminosis D in Dogs with Induced Endotoxemia


  • This study was performed at the College of Veterinary Medicine at North Carolina State University.
  • This study was presented as an abstract at the International Veterinary Emergency and Critical Care Society meeting in San Antonio in September 2010.

Corresponding author: Marie K. Holowaychuk, Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1; e-mail: mholoway@uoguelph.ca



Hypocalcemia is a documented electrolyte disturbance in people and animals with sepsis, but its mechanism is poorly understood.


To investigate mechanisms of hypocalcemia in dogs with experimentally induced endotoxemia.


Six healthy mixed breed dogs were included in this nonrandomized, placebo-controlled, crossover study.


Dogs initially were injected with placebo (0.9% NaCl; 1 mL, IV) and then lipopolysaccharide (LPS; 2 μg/kg, IV) after a 5-day washout period. Blood and urine samples were collected for measurement of serum total calcium (tCa), ionized calcium (iCa), total magnesium (tMg), ionized magnesium (iMg), parathyroid hormone (PTH), 25-hydroxyvitamin D (vitamin D), venous blood gases, and fractional excretion (FE) of calcium.


After LPS administration, body temperature increased and blood pressure decreased. Both iCa and tCa decreased (< .01), but iMg was not significantly different between control and LPS treatments. PTH concentrations increased (< .01) and vitamin D concentrations decreased (< .01). Venous pH, bicarbonate, base excess, and blood glucose also decreased (< .01). Urine tCa concentration was below the limit of detection for all dogs after LPS administration.


Hypocalcemia occurs during endotoxemia in dogs and is associated with hypovitaminosis D. Hypomagnesemia, hypoparathyroidism, alkalosis, and increased calciuresis are not associated with hypocalcemia in endotoxemic dogs.