25 December 1998

Handle-with-care plan for best condition

PROPOSALS to change pig handling in abattoirs, which can improve flow rates and cut stress, could be used on-farm to ensure pigs leave a unit in top condition.

Work by CAMBAC researcher Tracy Jones established a set of proposals for abattoirs which would let pigs display normal behaviour, such as natural walking speed, to match processing capacity of abattoir culling lines. This removes the stop-start motion of pig handling in abattoirs, which increases labour and risk of stress, says Ms Jones. The proposals – funded by MAFF, MLC and industry – are based on achieving a natural flowrate of pig movements which could be implemented to some extent on-farm, Ms Jones says.

For example, improving lighting in buildings and raceways in units could improve pig flow, as they prefer to moving towards light and dislike shadows, she says. "Also, where pigs have to negotiate tight corners, flow can be improved by increasing space or reducing group size," adds Ms Jones. The natural walking speed for pigs in a single file is 1000 pigs an hour past a given point. To cut this to meet abattoir processing capacity of 360 pigs an hour researchers suggest introducing a series of staggered gates which pigs walk around, similar to a slalom on a ski-run.

To encourage pigs to move down raceways, forward facing gates should be barred, allowing pigs to see where they are going. Back-gates should be fully sheeted to deter any temptation to retreat.

Ms Jones says pigs may excrete a fear hormone in faeces when moved in a stressful environment. Although not scientifically proven, she says it may be advantageous to wash race-ways between batches to remove any negative odours.

When loading pigs on to a lorry, ramps must be no steeper than 10í from horizontal for pigs to maintain a natural pace, she adds. That includes lorry tailgates; most loading ramps should be 75cm-80cm (2ft 6in-2ft 8in) from the ground to match UK lorries to allow this, she says. &#42