Strategies to improve animal welfare

Sub-project 3, “To define integrated, knowledge-based, practical species-specific strategies to improve animal welfare”, is divided into six work packages, and deliverables are already available for two of those. One of the objectives of work package 3.2, “Genetic solutions to welfare problems”, is to identify and record inherited genetic disorders affecting pig welfare as well as to unravel the genetic basis of functional traits in pigs, including leg weakness and longevity. Previous description of structure of the pig population under study is needed with regard to productive, reproductive and functional traits (deliverable 3.10). This population includes 20.000 sows of three different breeds and kept in 20 nucleus herds. Information on longevity, incidence of lameness and inbreeding coefficient has been recorded over the last 10 years and is available for analysis. A protocol has now been set up to record inherited genetic disorders and behavioural aspects with an affect on welfare.

Tail-biting is one of the welfare problems studied in work package 3.2, “Injurious behaviours”, and a protocol for a behavioural test to detect tail-biting propensity (deliverable 3.17) is available. In order to study individual differences in tail-biting propensity, data are being collected on two tail-biting propensity tests selected on the basis of previous research work. One involves presentation of a model tail (sash cord) attached to the wall of a pen. The other test involves presentation of the model tail attached to a heavy solid object placed on the floor of the pen. This test may more realistically simulate another animal lying in the pen than the ‘traditional’ tail-on-the-wall test. In both cases, we are investigating how group sizes affect behaviour in the tests: pigs are tested on their own, as in most previous studies, in pairs where the presence of a pen-mate may ameliorate potential fear responses to being isolated for testing, and in groups of 10 allowing us to examine whether the test can be carried out quickly and efficiently in larger groups. Pigs are tested for 10 min 1 week after weaning, and again 3-4 weeks later. Repeat testing allows us to search for consistency of response across time. The data collected should demonstrate the amount of individual variation in tail-chewing behaviour detected by the tests, and how consistent individuals are in their chewing behaviour across time. Out of the 6 test type / group size combinations that we are studying, the protocol that shows the best combination of high cross-time consistency and large individual variation will be selected for use in the main study.

Although no deliverables are due yet in the other work packages, experimental work is progressing well in all of them.

Xavier Manteca

Universitat Autonoma de Barcelona, Spain