Computerized food intake recording systems of various designs are used by research, centres and breeding companies to monitor the individual food intake of pigs kept in groups. In the present experiment, three feeder designs are compared in order to estimate the effect on performance and feeding behaviour. Ninety entire male pigs (34 (s.e. 0·6) kg) were allocated in three replicates to pens of 10 pigs; each pen containing one of three different feeder entrance designs: low (head-guard), medium (full-length standard race), and high (enclosed pneumatic race) protection against disturbance of the feeding pig. No significant differences were found between treatments in daily food intake, daily live-weight gain, food conversion ratio, number of visits per day and daily feeder occupation. Pigs with access to an enclosed race had longer visits than pigs on the two other treatments, and they also ate more per visit (4·8, 4·8 and 6·2 (s.e.d. = 0·37) min per visit; 172, 157, and 202 (s.e.d. = 11·1) g per visit; means of low, medium and high protection, respectively). The enclosed race was not only the most protective, it was also the most difficult to enter, and this decreased accessibility of the food may have given rise to the changed feeding pattern displayed by pigs using this type of race. Access to a feeder with low protection resulted in a faster rate of eating (36·9, 33·2, and 32·8 (s.e.d. = 0·82) g/min; means of low, medium and high protection, respectively) indicative of a more forced feeding behaviour.

A two-treatment experiment was made involving 340 crossbred pigs penned in groups of 20 and offered a cereal-based, non-pelleted diet ad libitum from one single-space hopper per pen supplying both food and water. Half the feeders were fitted with stalls which protected the feeding pig from its pen mates. The average number of visits per day to the feeder was reduced from 20·1 to 11·9 (s.e. 1·58, P<0·01) by fitting the stall and the average duration of each visit was increased from 2·06 min to 4·18 min (s.e. 0·298, P < 0·02). The total time of occupation and its circadian pattern were similar for both treatments There were reductions in the incidence of enforced withdrawals (12·7 v. 3·4 (s.e. 0·75), P < 0·001) and of pigs queuing (28·6 v. 84 (s.e. 2·35), P < 0·001) with the addition of a stall which also reduced the occurrence of tail biting. Although the stall improved pig welfare the anticipated reduction in food spillage was not evident.