Noninvasive sample collection for the genotyping of neonatal rats using adhesive tape

To develop a noninvasive sample collection method for genotyping, we compared PCR products from samples collected from neonates using five different brands of adhesive tape. Next, the youngest application age to distinguish genotypes was established. The tapes were applied on the backs of rats on postnatal day (PND) 10. DNA extracts from two brands provided clear PCR products that enabled genotype identification. The youngest age for distinguishing genotypes was PND 5; however, the youngest age that provided accurate results was PND 7. Thus, the present method allows for genotyping during the neonatal period without invasive burden and may improve animal welfare by refining.