Effect of diet composition on the production of rabbit breeding does housed in a traditional building and at 30°C

Fifty-seven crossbreed New Zealand White rabbit does were maintained in a traditional building (TB) or at a constant temperature of 30°C, and fed ad libitum on two diets with about 11.2 MJ digestible energy (DE) kg−1 dry matter (DM) and 121 g (Diet 1) or 193 g (Diet 2) crude fibre kg−1 DM. Records from 162 lactations were examined, using litter size as a covariate. Feed intake of the two diets was similar for the first 3 weeks of lactation, but litter mortality was higher (21.0 vs. 15.5%, P < 0.05) and litter liveweight gain lower (1.47 vs. 1.66 kg, P < 0.01) with Diet 2. The effect of the diets for the last 2 weeks of lactation was different in the TB from that at 30°C. DE intake of Diet 2 was higher in the TB (1480 vs. 1310 kJ kg−0.75 day−1, P < 0.001), but milk production and litter liveweight gain were similar. At 30°C, DE intake of both diets was similar, but milk production (98 vs. 112 g day−1, P < 0.05) and litter liveweight gain (2.11 vs. 2.36 kg, P = 0.093) were lower with Diet 2. Feed intake and performance of does and litters were reduced in the 30°C environment.