immediately after to enable urine collection urine from each animal will be collected for 22 hours in chilled collection tubes treated with 100 u03bcl of a 10 thymol solution 1 0 g 10 ml isopropanol and paraffin oil 100 u03bcl to prevent urine evaporation from the following interval post dosing 24 hours samples will be frozen at u2212 80 u00b0 c until analysis all sugars will be quantified by ion exchange hplc lama ratio total sucrose and total sucralose will be obtained per measurement on the first day of every week stool sample will be collected from every animal and screened for the presence of blood stool samples will also be collected at the termination of the study 50 100 u03bcl serum from animals in group 5 will be frozen until zonulin measurements made 100 u03bcl serum from animals from groups 1 4 at day 57 and at day 77 will be frozen at u2212 20 u00b0 c until zonulin measurements made animals found dead will be refrigerated and necropsied at the earliest possible time within working hours terminal body weight organ weights will not be taken from animals found dead protocol defined tissues will be collected moribund unscheduled animals that are sacrificed during normal working hours will be taken immediately to necropsy a terminal body weight will be taken and the animal will be necropsied protocol defined tissues for histology will be taken moribund unscheduled sacrifice animals that are sacrificed outside of normal working hours will be refrigerated after a terminal body weight and necropsied at the earliest possible time within.