Effects of short light regimes and lower dietary protein content on the reproductive performance of White Roman geese in an environment-controlled house

•Geese under short light regimes have higher laying intensity fertility, hatchability than under long light regimes.•Geese under short light regime at prelaying period along with low CP diet are sufficient to sustain regular reproduction.•Short light regimes with low CP diet would be benefit farmers in the perspectives of energy saving and prolonged laying period. The objective of this study is to investigate the effects of short light regimes and lower dietary protein content on the reproductive performance of White Roman geese in an environment- controlled house. Thirty-two ganders and 80 geese during the third laying period were allotted into 16 pens, randomly assigned into a split-plot design with two different lighting regimes: (1) short light regimes (SL) with 6.5h of light and 17.5h of dark (6.5L:17.5D), and (2) long light regimes (LL) with 19L:5D during the 6-wk prelaying period, followed by two different levels of protein diets (Low CP: 15% vs. High CP: 18%) for the laying period. The results showed that birds treated with the SL light regime had a heavier body weight compared to those treated with LL at the arrival of the peak period of egg production (6.19 vs. 5.87kg, P