2.2. Tissue sampling and preparation
At the end of the experiment, blood was first collected from the jugular vein into a heparinized tube, mixed, separated by centrifugation, and the plasma was stored at−20 °C. Food was then withheld overnight and the sheep were slaughtered. The liver was immediately collected, excised, either stored at −20 °C or quick-frozen in liquid nitrogen and stored at−80 °C.
In this study, all procedures involving animals were approved by the China Agricultural University Animal Care and Use Committee.