Usefulness of serum cardiac troponin I concentration as a marker of survival of harbor seal (Phoca vitulina) pups during rehabilitation

OBJECTIVE To measure serum cardiac troponin I (cTnI) concentrations in orphaned harbor seal (Phoca vitulina) pups at various points during rehabilitation in a seal rescue center and determine whether cTnI concentration was associated with survival during rehabilitation and duration of rehabilitation. DESIGN Serial cross-sectional study. ANIMALS Fifty-five 2-to 9-day-old harbor seal pups. PROCEDURES Blood samples for serum cTnI concentration measurement, CBC, and serum biochemical analysis were obtained from seal pups at admission into a seal rescue center, after 2 weeks of rehabilitation at the center, and prior to release. Serum cTnI concentrations were compared between seals that did or did not survive rehabilitation. RESULTS Median serum cTnI concentration was highest at admission (0.03 ng/mL). After 2 weeks, the median value was 0.01 ng/mL; prior to release, it was 0.01 ng/mL. Seal pups that were found to have died during or after rehabilitation (n = 7) had a significantly higher median serum cTnI concentration at admission (0.06 ng/mL) than did seal pups that survived rehabilitation (and for which the postrelease fate was unknown; 48; 0.03 ng/mL). No correlation was identified between serum cTnI concentration and duration of rehabilitation. CONCLUSIONS AND CLINICAL RELEVANCE The results of this study suggested some degree of myocardial injury was present in most of the orphaned seal pups admitted for rehabilitation. Measurement of serum cTnI concentration in seal pups at admission might provide prognostic information about their likelihood of survival during or after rehabilitation.