Hematologic and serum biochemical reference intervals for Formosan Sika Deer (Cervus nippon taiouanus) from a semi-free-ranging population in Taiwan

Abstract

The Formosan sika deer (Cervus nippon taiouanus), an endemic Taiwanese subspecies, holds a pivotal role in local conservation. This study addresses a significant knowledge gap by establishing population-specific reference intervals (RIs) for this species, as existing RIs are based on limited captive populations and may not accurately reflect the health of semi-free-ranging cohorts. We analyzed 632 sampling events from 232 healthy adult deer within Kenting National Park over 12 years (2013–2024). This study adhered to ASVCP guidelines, establishing instrument-specific RIs and employing linear mixed-effects models (LMMs) to evaluate the complex interactions among analytical instruments, sex, and body weight. Our results confirmed significant inter-instrument variations and showed that both sex and body weight significantly influence numerous hematologic and biochemical parameters. This study provides crucial, long-term RIs and a robust analytical framework, offering direct and practical implications for the future health management and conservation of this endemic subspecies.