2.3. Experimental design
For preweanling studies, pups were randomly assigned to
treatment groups within each litter (split-litter design). Adults were
assigned to treatment groups through a stratified design to assure
similar group body weights. Adults were dosed at 1 ml/kg, and pups
(PND11 or 17) were dosed at 2 ml/kg (allowing greater accuracy in
dosing volume). Dosing was staggered to allow testing and sacrifice at
the same time after dosing. Treatments were counterbalanced within
the day and across multiple days of testing where necessary.