EFFECT OF EARLY FEED RESTRICTION ON PERFORMANCE AND HEALTH STATUS IN GROWING RABBITS SLAUGHTERED AT 2 KG LIVE-WEIGHT

The effect of a time limited access to the feeders (8 h per d from 9 30 to 17 30) on fattening performance and health status was studied in rabbits reared until 2 kg live-weight as typical in the Spanish market For this purpose the same diet (10 5 MJ digestible energy/kg 38 9% neutral detergent fibre and 18 4%;:rude protein on dry matter basis) was used over two consecutive trials A total of 192 growing rabbits (96 in each trial) were weaned at 35 d and assigned to 2 different feeding treatments (continuously fed ad libitum or restricted from 35 until 49 d) In the first trial feed restriction reduced daily feed intake (94 3 vs 742 g P<0 001) daily weight gain (4:6 vs 27 1 g P<0 001) and impaired teed conversion rate (FCR) (2 28 vs 2 92 P<0 001) in the first 14 d after weaning Later on no feed restriction was applied and a compensatory growth was observed in previously restricted rabbits (44 8 vs 54 8 g/d P<0 001) Early restricted rabbits did not reach the Spanish commercial weight (2 kg) at 63 d of age and weighed less than full fed rabbits (1989 vs 1888 g P=0 001) Moreover feed restriction did not improve FCR in the whole fattening period (2 56 on average) The second trial was extended until 70 d to permit restricted rabbits to attain market weight However at that age live weight of restricted rabbits was also lower than that of rabbits always fed ad libitum (2285 vs 2101 g P=0 001) In the first trial no health problem was recorded (average mortality 1 04%) whereas in the second trial feed restriction allowed both mortality (25 6 vs 6 34% P=0 017) and morbidity (41 4 vs 12 7% P=0 004) to decrease The higher number of losses in the second trial made economic FCR differ from scientific FCR (3 63 vs 2 89 on average) in the 35-70 d period Moreover morbidity increased heterogeneity of fattening performance In conclusion the interest of feed restriction in Spanish fattening rabbit farms is mitigated by the conventional market weight Nevertheless in a context with high rates of digestive troubles a time-limited access to the feeder enhances health status on the farm and could justify the short delay necessary to reach slaughter weight