The effect of nose ringing of outdoor sows on foraging behaviour and pasture damage

Nose ringing of outdoor sows is widely practiced to reduce pasture damage, but may have both short and longer term implications for animal welfare. This study was carried out to assess the effectiveness of different forms of nose ring and the extent of behavioural modification which they caused.Six groups of 5 sows were allocated between three treatments: unrung (U), rung with three traditional boss-rings through the upper rim of the nasal disc (TR) or rung with a single bull-ring through the nasal septum (BR). Groups were placed in adjacent paddocks on undamaged grass leys at a stocking rate of 38 sows/ha. Pasture damage was assessed weekly by measuring proportions of grass, bare earth and overturned earth in 20 half-metre square quadrats per paddock on a fixed sampling pattern.