Acknowledgements Book of abstracts - Publicaties - Vlaanderen.be

Antonio Velarde presents Poster 23 during the poster sessions in the Aula.
Session theme 2: Assessing emotional state and human-animal relations
95
Poster 23
FACTORS AFFECTING BACKTEST OR TONIC IMMOBILITY TEST
RESULTS IN PIGLETS OF TWO PURE BREEDS
X. Fernàndez 1 , Q. Casellas 2 , J. Tibau 1 , A. Velarde 3 , E. Fàbrega 1
1 Centre Avaluació Porcí IRTA-Monells, Monells, Spain
2 Genètica i Millora Animal IRTA-Lleida, 25198 Lleida, Spain
3 Centre de Tecnologia de la Carn IRTA-Monells, Granja Camps i Armet, 17121, Spain
The Backtest and Tonic Immobility (TI) tests have traditionally been used in experiments with
piglets in order to assess behavioural strategies or coping styles. Some authors have shed doubt
upon these methodologies, since it may be difficult to correlate the response in the backtest or TI
with those seen in other behavioural tests carried out at other ages. Some of the drawbacks for the
backtest are to standardize aspects like the pressure applied to the piglets or to try to disentangle the
potential effect of body weight.
The present study aimed at evaluating the response towards a test based both on the backtest and the
TI test in piglets of two pure breeds (Landrace and Large White). A total of 119 piglets (64
Landrace, 55 Large White) were subjected to this test consisting of placing the piglet on its back
with a small sack on its throat (similar to TI test) but maintaining it when the piglets remained
immobile. Piglets were weighed at three and six weeks of age and classified as TI or non-TI piglets
according to their response to the test at three weeks of age two days after weighing them. The
latency until the first attempt to turn or until the moment the piglet managed to turn completely after
the worker removed his hands was recorded.
The data were analysed using the Kruskal-Wallis test and Spearman correlations (r). Weight of
piglets correlated with total time until piglets managed to turn completely (r=-0.35; p