To solve these problem toys should be suspended over the pens with rope or twine. This keeps them clean and still will allow the animals to manipulate them almost as freely as though they were on the floor of the pens (Grandin, 1986).

Chains are not very attractive enrichment gadgets for pigs (Horell and Ness, 1995; Hill et al., 1998). Pigs will play with chains, but they prefer to play with pliable objects when they are given a choice (Grandin, 1988).

Cloth strips are particularly effective enrichment items (Grandin and Curtis, 1984). Strips of old bedsheet about 3 in. wide and 24 in. long can be easily tied to the fence and replaced when they get dirty.

Environmental enrichment will make the animals calmer and less likely to be startled by sudden noise (Grandin, 1986; Grandin et al., 1987) or by people (Pearce et al., 1989; Moore et al., 1994).

Pigs who are distracted in species-adequate ways will also show less apathy and engage in less stereotypical (Apple and Craig, 1992; Haskell et al., 1995) and anti-social activities (Schaefer et al., 1990; Arey, 1993) such as biting (Fraser, 1975; Beattie et al., 1995) and chewing ears and tails of their penmates (van Putten, 1979; Simonsen, 1990; Beattie et al., 1993).