Hypernatremia in neonatal elk calves: 30 cases (1988-1998).

OBJECTIVE

To characterize hypernatremia in neonatal elk calves, including clinical signs, incidence, physical examination findings, and possible causes.

DESIGN

Retrospective case series.

ANIMALS: 26 neonatal elk calves were examined; 4 calves were evaluated twice, for a total of 30 examinations.

PROCEDURE: Medical records were reviewed for signalment, history, physical examination findings, results of diagnostic tests, and response to treatment. Hypernatremia was defined as serum sodium concentration > 153 mEq/L.

RESULTS

Hypernatremia was diagnosed in 14 calves and was significantly associated with diarrhea, high WBC count, high anion gap, and high serum concentrations of albumin, chloride, creatinine, and urea. Hypernatremia was not significantly associated with survival, but high serum albumin concentration and rectal temperature were significantly associated with survival of calves. Animals given antibiotics and electrolyte solutions orally prior to evaluation were significantly more likely to die than those untreated. Dehydration was a common reason for evaluation but was not significantly associated with survival.

CONCLUSIONS AND CLINICAL RELEVANCE: Hypernatremia was significantly associated with diarrhea. Treatment of diarrheic elk calves is often the same as that used in bovine calves with diarrhea; however, bovine calves are commonly hypo- or normonatremic. Our experience suggests that treatment protocols used in bovine calves are unsatisfactory for elk calves. The rate at which serum sodium concentration is reduced should be < 1.7 mEq Na/L/h to avoid development of neurologic signs associated with iatrogenically induced cerebral edema.