The present invention provides animal models and methods for the evaluation of maternal treatments that could improve or compromise the epigenetic state, the imprinting, or the DNA methylation and thus the health or disease propensity, of human or other mammalian offspring. In particular, the present invention provides animal models with naturally occurring epigenetic variation for the evaluation of treatments through effects on the epigenetically determined and imprinted characteristics of coat color, coat color pattern, DNA methylation, long terminal repeat (LTR) expression and LTR activity of offspring.