Coping characteristics and performance in fattening pigs

Pigs vary in their individual behaviour in response to stress, and this coping behaviour can be measured with a backtest. In this test, a piglet is put on its back and escape attempts are counted during 1 min. Backtest results are linked to individual performance, and regrouping at 9 weeks of age on the basis of coping characteristics can influence production parameters. In the present study, piglets were cross-fostered at 3 days of age on the basis of backtest results, and pens with only active piglets (HR), with only reactive piglets (LR) and mixed pens were formed next to original litters. At 9 weeks animals were mixed and moved. The relation between backtest results and production performance was investigated. Cross-fostering induced a change in backtest results, resulting in approximately the same mean backtest results in each group and consequently on pen level no relations were found between initial coping behaviour and performance. Individual backtest results were linked to production parameters: active animals tended to grow faster and have a leaner carcass. If pig breeding companies would use the backtest to select the most active animals that are potentially the best performers, aggressive behaviour should also be considered (e.g. as part of the breeding goal), because of the link between activity and aggressive behaviour. (C) 2003 Elsevier B.V. All rights reserved.