Reference Intervals for Plasma Biochemical Variables by Point-of-Care Testing in Captive Black-tailed Prairie Dogs (Cynomys ludovicianus)

Black-tailed prairie dogs (Cynomys ludovicianus) are kept in zoological collections, maintained as companion pets, and are tested in field and laboratory settings. Biochemical analysis for routine health and research purposes can be performed by using point-of-care (POC) testing; however, analyzer- and species-specific reference intervals need to be determined. In this prospective study, 50 captive-raised sexually intact prairie dogs (16 females, 34 males) underwent plasma biochemical analysis by using a veterinary POC biochemical analyzer. We used a manufacturer-predetermined profile of 14 analytes: albumin, ALP, ALT, amylase, BUN, calcium, creatinine, glucose, potassium, sodium, phosphorus, total bilirubin, total protein and globulin. A subset of 17 samples was tested concurrently for the same 14 analytes by using a reference laboratory analyzer, and we determined RI for the POC analyzer for these 14 biochemical analytes. Sex had a significant effect on albumin and creatinine values, which were higher in females than males, and on ALT, which was lower in females. In addition, age had an effect on 9 plasma analytes: juvenile animals had higher plasma concentrations of albumin, ALP, ALT, BUN, and glucose than adult animals, whereas adults had higher concentrations of creatinine, sodium, total protein, and globulins. Only calcium and BUN had acceptable analytical agreement between the POC and reference analyzers. The reference intervals determined in this study can aid clinicians and researchers performing POC plasma biochemical analysis in prairie dogs, providing that they consider potential analyzer-, sex-, and age-related effects.