Case report: Measuring the Circulating Bone Metabolic Markers of Two Asian Elephant (Elephas maximus) Calves Around Weaning

Abstract

　We measured the serum activities of the bone-specific isoenzyme of alkaline phosphatase (ALP3) and tartrate-resistant acid phosphatase 5b (TRAP5b), as osteoblastic bone formation and osteoclastic bone resorption markers, respectively, in two zoo-managed Asian elephant calves during the 4-month period around weaning (2 months before and after weaning). The serum ALP3 and TRAP5b levels decreased after weaning; the levels were significantly higher in the pre-than post-weaning period. These results suggest that osteoblastic bone formation and osteoclastic bone resorption slowed after weaning. Breast milk feeding of Asian elephants may play a significant role in osteoblastic and osteoclastic bone metabolism during the growth period.