At the termination of the experiment (d 21), 4 birds
per cage were euthanized by intracardiac injection with
T61 (0.1 mL/kg of BW; Intervet Nederland BV, Boxmeer,
the Netherlands), and the left and right tibia
were removed and pooled per replicate. A pooled sample
of 4 right tibiae per cage was autoclaved for 20
min and cleaned of soft tissue. The pooled sample of
4 right tibiae was dried for 24 h at 103°C and then
ashed at 550°C in a muffle furnace. This was followed
by wet ashing of bone ash with HNO3 and H2O2. Left
tibiae and remaining right tibiae were stored at −20°C.
Tibia Zn was determined in the tibia ash fraction (ISO
6869:2001).