“…Glycine inhibits the intestinal injury caused by tumor necrosis factor alpha ( TNF-α ) in the chemical colitis model ( McCole, 2010 ), and restores the glutathione ( GSH ) to oxidized GSH ( GSSG ) ratio reduced by oxidative stress ( Wessner et al, 2003 ). Glycine's application has been widely recognized in various disease model of the medical field, such as ischemia-reperfusion injury, shock, organ transplantation, alcoholic hepatitis, liver fibrosis, arthritis, tumor, and drug toxicity ( Amelio et al, 2014 ; Effenberger-Neidnicht et al, 2014 ; Al-Saeedi et al, 2019 ; Alves et al, 2019 ; Shafiekhani et al, 2019 ). However, there are few studies on the application of glycine under stressful conditions in poultry over the past 20 yr.…”