Trace mineral reserves for reproduction and development in muskoxen

Abstract

In muskoxen (Ovibos moschatus), trace minerals required for reproduction and development are unknown. I described use of copper in pregnant muskoxen and concurrent accumulation of copper in fetuses. Utilization of copper was examined in neonates during early development and importance of milk as a source of copper was assessed. Additionally, I examined the effect of maternal copper supplementation during gestation on copper reserves acquired in-utero, and during lactation on mineral status of milk. During gestation, the fetus must acquire reserves of copper adequate to support early neonatal development because milk is a poor source of copper. The transition from milk to a forage-based diet may compromise immune function, growth, and survival of young as reserves established in-utero are likely depleted by that time. Maternal supplementation of copper during gestation and lactation provided little benefit to young, neither increasing mineral reserves in the fetus nor mineral content of milk. Nonetheless, supplementation during gestation may offset maternal costs.