The liver is the largest detoxification organ in the human body. RNA sequencing (RNA-seq) analyses of liver samples were performed to investigate the effects of high ammonia levels (ammonia exposure at 75 ± 5 ppm), a low ammonia level (ammonia exposure at 5 ± 5 ppm) was set as control group, on the metabolism and detoxification capabilities of laying ducks. Overall design: A total of 176 Shanma laying ducks (Fujian Longyan Shan Ma Duck Station, Longyan, China), aged 150 days, with comparable bodyweights were selected and randomly allocated to one of two groups: a high ammonia group (ammonia exposure at 75 ± 5 ppm) or a low ammonia group (ammonia exposure at 5 ± 5 ppm). The two groups were housed in separated atmospheric ammonia controlled rooms with free access to the same diet and water. Amnonia level was controlled by specialized equipment. The feeding experimental period was 30 days from day 200 to 230.