Short communication: Effect of substituting hydroponic green barley forage for a commercial feed on performance of growing rabbits

[EN] The effect of replacing a commercial feed with hydroponic green barley forage (HGBF) was studied on productive performance and carcass yield of growing New Zealand rabbits. Four mixed diets based on a pelleted commercial feed (15.7% crude protein and 12.3% crude fi ber) were made by substituting wet HGBF (containing 16.1% dry matter, 2.18% crude protein and 2.36% crude fi ber) for the commercial feed (0, 10, 20 and 30%). Sixty-four rabbits, 35 d of age and with an average body weight of 917±9.7 (standard error) g were assigned to the 4 treatments and caged in groups of 4 rabbits (2 females and 2 males/cage). HGBF was grown for 15 d, and administered immediately after harvesting, including the radicular pad (roots and seed) and leaves. Feed intake and growth rate from 35 to 70 d of age were recorded. The rabbits were then slaughtered and the dressing-out percentage computed. Both dry matter feed intake and growth rate decreased linearly by 0.75±0.091 g/d (P<0.001) and 0.20±0.040 g/d (P<0.001) per unit of HGBF increase. Rabbits consumed daily all the HGBF offered 0, 2.3, 4.6 and 7.0 g DM for 0, 10, 20 and 30% substitution level, respectively. Feed conversion (average 3.26±0.026) and carcass yield percentage (average 58.1±0.32 %) were not affected by treatments. It was therefore concluded that replacing pelleted commercial feed by wet HGBF impaired growth performances.