Effects of Different Lighting Regimes on Reproductive Performance of Rabbit Does and Growth of Weaned Rabbits

Light is a critical environmental factor in rabbit production, yet systematic evaluation of low-light conditions for both reproduction and growth remains limited. This study assessed the effects of three combined lighting regimes: bright–dark (80 lx, 16L:8D for 6 days pre-AI plus 0–2 lx, 0L:24D during other periods), bright–dim light (80 lx, 16L:8D for 6 days pre-AI plus 4–6 lx, 24L:0D during other periods), and bright–bright light (80 lx, 16L:8D for 6 days pre-AI plus 75–85 lx, 12L:12D during other periods) on the reproductive performance of nulliparous Hyla does (n = 553 in total, with 185, 184, and 184 does in the bright–dark, bright–dim light, and bright–bright light groups, respectively) across three consecutive 42-day parities, and three single light regimes (dark, dim, bright) on the growth of weaned rabbits (n = 184 per group), over 20 days with digestion and metabolism trials. In the first parity, the bright–dark and bright–dim groups had significantly larger litter sizes and more live-born kits than the bright–bright group, whereas the average individual birth weight of live-born kits was significantly higher in the bright–bright light group than in the bright–dark group, with no significant difference between the bright–bright light and bright–dim groups. By the third parity, dim light improved total litter weight and live-born kit weight compared with bright light. Overall, the bright–dark regime showed more advantages in total and live-born litter size. For weaned rabbits, the dark regime significantly increased average daily gain and feed intake compared with the bright light regime, with higher crude protein and fiber digestibility. The dim regime showed intermediate values for several reproductive and growth outcomes. These findings provide a basis for the further evaluation of stage-specific lighting management, with welfare and behavioral outcomes requiring assessment before practical implementation.