Five grams of each ground sample from skin and meat, 0.5gm ground feed sample, and 5 mL of blood were weighed into a crucible and ignited on a hot plate until the smoke stopped. The ash containing the crucible was placed into a muffle furnace at 600°C for 2 h. After it was cooled to room temperature, 30 mL of HCl (50%) was added and boiled on a hot plate and then cooled again to room temperature.