Preferences of sheep for different types of pen flooring

In countries where the climate makes it practical with indoor housing during cold periods of the year and access to straw is limited, e.g. Iceland and Norway, housing of sheep on slats or expanded metal floors is common practice. However, European regulations for organic farming require that all animals should have access to a lying area with solid floor. The objective of this experiment was to investigate sheep preferences for different types of pen flooring.

In Experiment 1, a total number of 16 ewes, divided into four groups, were subjected to four different treatments. In each treatment, the ewes could choose between two lying areas with one of the following flooring materials: (1) solid wood versus rubber mats, (2) expanded metal versus solid wood, (3) solid wood versus straw, (4) expanded metal versus straw. In Experiment 2, a total number of eight ewes were individually subjected to the same treatments, first fully coated and then sheared. The ewes were video taped for 48 h in each treatment period.

In Experiment 1, the first animal that lay down after feeding preferred to lie down on straw or wood to expanded metal and straw to wooden floor (P < 0.05), but this first choice did not reflect the overall flooring preference for unsheared ewes. The groups of unsheared ewes showed no significant preferences for lying area.

In Experiment 2, single housed, unsheared ewes preferred wooden floor to rubber mats (P < 0.05), and tended to prefer expanded metal floor to straw (P = 0.08). There were no significant preferences in the two other treatments. After shearing, the ewes’ preferred wooden floor to expanded metal (P < 0.05), straw to wooden floor (P < 0.05), and straw to expanded metal floor (P< 0.0001). There were no significant preferences between rubber mats and wooden floor. Mean lying time (% of observations) for all treatments was 64.7% for unsheared ewes, and there were no significant differences between treatments. Mean lying time (% of observations) for all treatments the first 2–3 days after shearing was 43%. Significant differences in pre-shearing versus post-shearing lying times (% of observations) existed when the ewes were housed in pens with no straw (P < 0.05), this was not the case when the ewes had access to straw.

In conclusion, sheared but not unsheared ewes, preferred softer floors with low thermal conductivity (straw and wood). The less dramatically reduction in lying time (% of observations) after shearing when the ewes had access to straw, suggest that access to straw the first weeks after shearing may improve animal welfare.