FEEDING-BEHAVIOR OF GROWING PIGS USING SINGLE OR MULTISPACE FEEDERS

Most studies of the feeding behaviour of group housed growing pigs hav e used computerized single-space feeders, which result in a pig:trough ratio which differs from that found on commercial pig farms, where mu lti-space feeding troughs are used. The present experiment compared th e feeding patterns of group housed, growing pigs given access to eithe r a computerized single-space feeder or a four-space feeding trough. E ighty cross-bred entire male pigs (initial live-weight 32.3 +/- 0.62 k g; mean +/- s.e.) were allocated to groups of ten, and each group give n access to one of the two feeder types. The feeding behaviour was mea sured automatically from the single-space feeders, and determined for the four-space trough treatment from video tapes, where feeder visits were counted and timed, combined with daily weights of the food eaten per group, Pigs given access to a four-space trough visited the feeder much more frequently (84.5 vs. 14.3 visits day(-1); s,e.d. = 5.3; P < 0.001), and for shorter durations (0.67 vs. 4.67 min per visit: s.e.d . = 0.36; P < 0.001), eating only a little per visit (24 vs. 149 g per visit: s.e.d, = 14; P < 0.001) compared with pigs kept in the groups given access to a computerized single-space feeder. High levels of all elomimetic feeding were shown by pigs using the four-space trough, wit h 61% of all visits initiated whilst one or more pigs were already fee ding. Also, a higher proportion of visits were made adjacent to a feed ing pig than would have been expected by change (0.59 vs. 0.50; P < 0. 001). No significant differences were found between treatments in the rate of feeding or daily feeder occupation. The differences in feeding pattern did not result in differences in production variables in term s of daily feed intake, daily live-weight gain, and feed conversion ra tio, A bout analysis was applied to the data using frequency distribut ions of length of intervals between visits. For pigs using the four-sp ace trough visits could justifiably be collapsed into feeding bouts, w hereas this was not the case for visits displayed by pigs using the si ngle-space feeder. Pigs using the four-space trough showed a high freq uency (0.64) of changes between spaces within each feeding bout. This may represent exploratory or sampling behaviour, which may aid the pig in obtaining a nutrient-sufficient diet should many different food it ems be available, Comparing feeding bouts from the four-space feeders to visits from the single-space feeders revealed no differences betwee n the two types of feeders, indicating that single-space feeders const rain the feeding pattern mainly in terms of preventing changes between trough-spaces within bursts of feeding.