Social reinstatement behaviour of broiler chicks tested in a T-maze is not affected by test order, right-left preferences or time-of-day.

MARIN R. H.; JONES, R. B.

Atlanta, Georgia, Estados Unidos

Congreso; International Poultry Scientific Forum.; 2000

Southern Poultry Science Society

Social reinstatement behavior of broiler chicks tested in a T-maze is not affected by test order, right-left preferences, or time-of-day.. R. H. Marin*1 and R. B. Jones2,R. H. Marin*1 and R. B. Jones2, 1CRILAR (CONICET), Anillaco, La Rioja, Argentina, 2Roslin Institute, Roslin, Midlothian, Scotland. Roslin, Midlothian, Scotland. CRILAR (CONICET), Anillaco, La Rioja, Argentina, 2Roslin Institute, Roslin, Midlothian, Scotland.. Broiler chicks show pronounced individual differences in the latency to traverse a T-maze and thereby reinstate visual contact with their companions. Chicks that completed this task quickly then grew faster both in the laboratory and on farm, they were more sociable, and they showed lower adrenocortical responses to a selected stressor than did their slower counterparts. Before we can recommend this simple, rapid, non-invasive test as a selection criterion for future commercial breeding programmes we must ensure that T-maze behaviour is not sensitive to potentially confounding variables like the order of testing, existing preferences to turn right or left at the junction of the maze, or the time-of-day. Here, 240 newly hatched, mixed-sex broiler chicks (Cobb) were randomly allocated to 12 groups of 20. At 2 days of age a group of 20 chicks was placed in the brood area of each of two T-mazes at 08.30 h; the brood areas were positioned on either the right or the left sides of the mazes. After 30 min acclimatisation one chick from each of group was placed in the isolation chamber of the T-maze and the time it took to traverse the maze was recorded. This procedure was repeated until all 20 chicks and all 12 groups had been tested. Testing was completed in one day and the locations of the brood areas were rotated after each block of 20 tests. Analyses of variance revealed no detectable effects of: test order, right or left location of the brood area, or time-of-day and no significant interactions. These findings strongly suggest that the above variables would not confound the classification and possible genetic selection of broiler chickens based on their social reinstatement responses in a T-maze. Key Words: Broiler chickens, T-maze behavior, Social reinstatement: Broiler chickens, T-maze behavior, Social reinstatement