Chronic sucrose preference Prior to the experiment animals were exposed for two weeks to two bottles of tap water. During the following 6 weeks animals received a choice between water and a 2% or 5% sucrose solution and sucrose preference was calculated for the last four weeks according to the weekly protocol. Every week, mice were given access to two drinking bottles positioned one next to the other. Twenty-four hour fluid consumption was measured by daily weighing the bottles during the last hour before the onset of the dark phase (9:00-10:00 AM). All interaction with the animals was conducted during this period. Sucrose solution (2% and 5% prepared in tap water) was placed in one bottle and the tap water in the other. In order to study fluctuations in sucrose preference over time, we designed a one week protocol according to a previously described method (Taliaz, et al 2011). For day one and two of the week, the sucrose solution was placed on the left side of the cage and water on the right. On day three of the week, only tap water was administered on both sides and all animals were weighed. On day four and five the sucrose solution and water were placed in reverse to control for side preference. On day six and seven of the week animals received two tap water bottles. Sucrose preference for each mouse was defined as the average percentage of sucrose consumption of the total liquid consumption. Sucrose and total liquid intake were calculated by normalizing the volume of consumed sucrose solution or total liquid intake with the animal weight for that week. Only day two and day five were included in the analysis. This procedure was repeated for six weeks, out of which the first two weeks represent the adjustment period and were not taken into the analysis. Social interaction test
Chronic sucrose preference Prior to the experiment animals were exposed for two weeks to two bottles of tap water. During the following 6 weeks animals received a choice between water and a 2% or 5% sucrose solution and sucrose preference was calculated for the last four weeks according to the weekly protocol. Every week, mice were given access to two drinking bottles positioned one next to the other. Twenty-four hour fluid consumption was measured by daily weighing the bottles during the last hour before the onset of the dark phase (9:00-10:00 AM). All interaction with the animals was conducted during this period. Sucrose solution (2% and 5% prepared in tap water) was placed in one bottle and the tap water in the other. In order to study fluctuations in sucrose preference over time, we designed a one week protocol according to a previously described method (Taliaz, et al 2011). For day one and two of the week, the sucrose solution was placed on the left side of the cage and water on the right. On day three of the week, only tap water was administered on both sides and all animals were weighed. On day four and five the sucrose solution and water were placed in reverse to control for side preference. On day six and seven of the week animals received two tap water bottles. Sucrose preference for each mouse was defined as the average percentage of sucrose consumption of the total liquid consumption. Sucrose and total liquid intake were calculated by normalizing the volume of consumed sucrose solution or total liquid intake with the animal weight for that week. Only day two and day five were included in the analysis. This procedure was repeated for six weeks, out of which the first two weeks represent the adjustment period and were not taken into the analysis. Social interaction test
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