Domestic chickens drinking from open water

In a flock of 283 Lohman Brown laying hens kept in a mobile barn with access to an outdoor run three round plastic trays (41cm diameter, 4cm deep) were presented in the free-range area. Each tray contained either water, sand, or nothing (empty control), of which the location was systematically alternated daily. The three treatments were intended to see whether additional resources offered were used (sand), whether trays alone were particularly attractive (empty control), or whether it was specifically the water availability that made the tray attractive (water). Both direct observations (twice daily for 15min each with 30s intervals) and video recordings (motion-detected video, totalling 3110 video clips) were used to assess resource use over a period of 18 days. The number of hens being in each tray type was analysed with a linear mixed-effect model in R studio. The layers intensively used the water tray to drink, generally depleting the water trays early in the day, often within less than 30 min. So, we found no evidence of water bathing in chickens. Instead, we observed a high drinking motivation, even though the birds had ad libitum access to nipple drinkers in the barn and a normal water consumption from those nipples. This suggests that drinking from open water may be a behavioural need that necessitates further investigation.