Performance, water intake and feeding behaviour of two groups of 30 (trial 1), 40 (trial 2) or 50 (trial 3) weaned pigs offered either pellets or meal of the same formulation were compared.
Average daily weight gains (ADG) were higher for pigs given pellets rather than meal in trials 2 (413 v. 363 g/day,
P < 0·001) and 3 (356 v. 324 g/day, P < 0·05). Mean daily water intake (DWI) was higher with meal than with pellets but only during trial 1 (2·31 v. 1·65 I/day, P < 0·01).
The occupation time (ОT) and the number of animals using the feeder simultaneously (N) were higher when pigs were given meal rather than pellets, whatever the animal density: trial 1: 82·6 v. 69·9% (P = 0·05) and 3·8 v. 2·3 (P < 0·01); trial 2: 90·9 v. 77·9% (P > 0·05) and 5·2 v. 3·1 (P < 0·01); trial 3: 96·2 v. 83·6% (P < 0·05) and 5·9 v. 3·8 (P < 0Ό1). When using pellets, ОT and N were always significantly lower during the night than during the day but when using meal in groups of 40 and 50, ОT during the night was almost as high as during the day.
The greater the group size, the lower were ADG (both diets) and DWI (only with meal) and the higher were ОT and N (both diets). Furthermore, significant linear and curvilinear regressions of DWI, ОT and N according to time were calculated.
In conclusion, pigs need more time to eat meal than to eat pellets. Thus the number of pigs per feeder has to be adapted to the food presentation. Too high a number of pigs per feeder impairs feeding behaviour and eventually welfare, by preventing preferential diurnal feeding activity and this may affect productivity.