Free-roaming cats in New York, NY, USA, that presented to a trap–neuter–return program were surveyed for biochemical data. One hundred and one cats had blood collected for a plasma biochemistry panel after the induction of surgical anesthesia. Reference intervals for 18 analytes were generated for the sample population, along with age-specific reference intervals when statistically appropriate. Age groups (juveniles and adults) differed in 10 of the 18 analytes measured, including protein levels and albumin/globulin ratio, aspartate aminotransferase, alkaline phosphatase, creatine kinase, creatinine, phosphorus, calcium and potassium. No differences were found between males and females. This is the first report of biochemical reference intervals for a group of free-roaming cats within the USA.
