“Hay-bags” and “Slow feeders”: Testing their impact on horse behaviour and welfare

The temporal distribution of feeding behaviour is of primary importance in grazing herbivores. Many domestic horses are managed under conditions far removed from the natural environment. For example, restricted access to roughage may induce health problems such as gastric ulceration, but also be a source of emergence of stereotypic behaviours, revealing an altered welfare. Devices such as hay-nets/bags and 'slow-feeders' have been developed and aimed to increase the time horses spend feeding on roughage. To assess the impact of these devices on horse welfare we observed the behaviour of 38 domestic horses in their home stall environment. Horses were subjected to different hay-provisioning treatments; 1) hay on the stall ground (usual situation); 2) hay-bags hung at one of the stall walls; 3) hay in a slow-feeder positioned in the corner of the stall. All horses were submitted in a random order to the three conditions for three weeks each time. We found that horses increased their time feeding on hay in both the hay-bag and the slow-feeder treatments compared to the hay on the stall ground treatment. While the hay-bag distribution was associated with an increase of frustration behaviours, the slow-feeder reduced “undesirable” behaviours, such as stereotypic behaviours, and increased “friendliness” towards humans. These results emphasize the importance of identifying feeding strategies and/or devices that improve feeding distribution and improve horse welfare.