The behavioural priorities of laying hens: the effects of two methods of environment enrichment on time budgets.

In the first experiment, a comparison was made of the time budgets of laying hens (Gallus gallus domesticus) in an enriched condition, in which various objects were added to their pen, and an unenriched condition, the same pen but without these objects. Assuming a fixed time budget, greater choices in the enriched condition would increase some behaviours at the expense of others, providing a relative measure of importance. In a second experiment, one group had woodchips on the floor with food and the other had woodchips on the floor without food (available from a hopper). In the first experiment, frequency of dust-bathing decreased in the enriched condition. Hens in the unenriched condition spent more time preening, drinking, social pecking at others and being aggressive which also increased in the second experiment in the hopper food condition. In both experiments, there was no difference in the amount of time feeding and also pecking and scratching even though food was not available in the litter in the unenriched condition. The results of the second experiment show that feeding on the floor alone, i.e., not in combination with environmental enrichment, also reduces aggression, whereas it has no influence on social pecking.