In a semi-na
tural environmen
t, a lo
t of
the daily ac
tivi
ty of pigs is spen
t in explora
tory and foraging behaviour. Providing enrichmen
t ma
terial a
ttrac
tive
to
the pigs bo
th over
the shor
t and long
term is
therefore impor
tan
t in in
tensive housing sys
tems. This s
tudy aimed
to inves
tiga
te
the effec
t of four
types of poin
t-source enrichmen
t ma
terials and four
types of li
tter on
the behaviour of finishing pigs. In experimen
t 1, pigs were offered cu
t s
traw or cu
t s
traw enriched wi
th maize kernels as li
tter on
the lying area, as well as a cylindrical dispenser filled wi
th a compressed s
traw block or a s
traw rack filled wi
th cu
t s
traw. In experimen
t 2, chopped s
traw or chopped
Miscanthus giganteus was provided as li
tter on
the lying area, along wi
th a s
traw-pelle
t dispenser or bark compos
t in a
trough. In bo
th experimen
ts, 96 finishing pigs wi
th undocked
tails were housed in groups of six pigs in pens wi
th par
tly-sla
tted floors. Half of
the groups were fed res
tric
tively,
the o
ther half ad libi
tum. Every
three weeks,
the enrichmen
t ma
terials were replaced. Explora
tory behaviour direc
ted
towards
the enrichmen
t ma
terial,
the pen equipmen
t and pen ma
tes was videorecorded and analysed by means of one-minu
te focal-scan sampling on
the second and eigh
teen
th day af
ter provision of a new enrichmen
t ma
terial. Da
ta were analysed using linear mixed-effec
t models.
In both experiments, the frequency with which the enrichment material was explored was influenced by the interaction of type of material and day (p < 0.001). On the second day after provision of enrichment, the favoured material was cut straw enriched with maize kernels in experiment 1, and the straw-pellet dispenser in experiment 2. On day 18, straw as litter with or without maize, the straw rack, chopped straw, chopped Miscanthus giganteus and the pellet dispenser were used with a similar, and still relatively high, frequency. The least-explored materials were the straw block and bark compost. In both experiments, pigs fed ad libitum explored the materials less than half as frequently as those fed restrictively (p < 0.001). Manipulation of the pen showed a pattern inverse to that of manipulation of the material, but a similar pattern with respect to feeding regime. Materials had no discernible influence on the manipulation of pen mates. In conclusion, our results indicate that both the point-source enrichment and the litter materials provided constituted adequate enrichment for small groups of finishing pigs.