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

Objective-To characterize hypernatremia in neonatal elk carves, including c linical signs, incidence, physical examination findings, and possible cause s. 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 e xamination 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 asso ciated with diarrhea, high WBC count, high anion gap, and high serum concen trations of albumin, chloride, creatinine, and urea. Hypernatremia was not significantly associated with survival, but high serum albumin concentratio n and rectal temperature were significantly associated with survival of cal ves. Animals given antibiotics and electrolyte solutions orally prior to ev aluation were significantly more likely to die than those untreated. Dehydr ation was a common reason for evaluation but was not significantly associat ed with survival. Conclusions and Clinical Relevance-Hypernatremia was significantly associat ed with diarrhea. Treatment of diarrheic elk calves is often the same as th at used in bovine calves with diarrhea; however, bovine calves are commonly hypo- or normonatremic. Our experience suggests that treatment protocols u sed in bovine calves are unsatisfactory for elk calves. The rate at which s erum sodium concentration is reduced should be < 1.7 mEq Na/L/h to avoid de velopment of neurologic signs associated with iatrogenically induced cerebr al edema.