Serum vitamin D in sanctuary chimpanzees (Pan troglodytes) in range countries: A pilot study

BACKGROUND: Vitamin D is essential for skeletal health, calcium homeostasis and general health. The major and more stable form of vitamin D in circulation is 25‐hydroxyvitamin D (25‐OH‐D); this is the most valuable indicator of vitamin D status. There are studies on laboratory and zoo‐housed chimpanzees; however, serum vitamin D status has not been documented in chimpanzees in range countries. OBJECTIVES: (1) Determine the range of circulating 25‐OH‐D concentrations in chimpanzees in range countries. (2) Assess the influence of age, sex, and sun exposure on 25‐OH‐D serum concentrations. METHODS: Opportunistic blood samples were obtained from 127 clinically healthy chimpanzees. Serum 25‐OH‐D concentration was measured with a commercially available competitive ELISA. RESULTS: The median overall 25‐OH‐D concentration for chimpanzees in range countries was 46.24 nmol/L (range: 17.10–109.23 nmol/L). Males had a significantly lower concentration (40.15 nmol/L) than females (49.61 nmol/L), and infants (37.99 nmol/L) had a significantly lower concentration than adults (46.04 nmol/L). Concentrations of 25‐OH‐D in chimpanzees in sunnier habitats were significantly higher compared to thick tropical forest habitat. CONCLUSION: The present constitutes a large dataset of serum 25‐OH‐D concentrations in range country sanctuary chimpanzees and contributes to document normal ranges. Age, sex, and sun exposure influenced serum concentrations of 25‐OH‐D in sanctuary chimpanzees.