FREE-RANGING OCELOTS (LEOPARDUS PARDALIS): HEMATOLOGY AND SERUM CHEMISTRY REFERENCE VALUES

Acquiring baseline physiologic data for animals from a free-ranging wildlife species is an elusive objective. Between 1990 and 2020, a monitoring program on the last population of ocelot (Leopardus pardalis) to inhabit public land in the United States yielded 139 blood samples from 67 individual animals. Ocelots were live trapped and anesthetized for census and radiotelemetric studies. The protocol included morphometrics, photographs, electronic identification, and blood collection. Complete blood count and serum chemistry were performed, and after sorting of the data to remove unhealthy individuals and occasional outliers, the dataset provided sufficient information to compute reliable reference intervals (RI). According to the American Society of Veterinary Clinical Pathology consensus guidelines, RI should be elaborated by using data from each reference individual only once. RI by random selection was determined when several measurements were available over time from one same animal. Second, RI were also computed allowing repeat measurements for reference individuals, exclusively to characterize and quantify the effect on the data distribution and on the generated RI. A summary of published RI for various species of wild felids is also presented. The variations observed between species is due not only to species differences but also to variation in measurement methods and RI study design. Overall, accurate blood work interpretation requires RI generated from a healthy population, with defined measurement methods and state-of-the-art RI study design. Of note, calcium is typically tightly regulated in all mammals, as illustrated by the narrow RI (8.5-10.8 mg/dl); conversely, finding a narrow RI in calcium across as many as 49 healthy individuals suggests a high-quality design study.