in rats in first 2 weeks after birth ~80%: in guinea pig in first postnatal month ~20% % of granule cells added to dentate gyrus
||Josselyn SA, Frankland PW. Infantile amnesia: a neurogenic hypothesis. Learn Mem. 2012 Aug 16 19(9):423-33. doi: 10.1101/lm.021311.110 p.427 right column 2nd paragraphPubMed ID22904373
||Schlessinger AR, Cowan WM, Gottlieb DI. An autoradiographic study of the time of origin and the pattern of granule cell migration in the dentate gyrus of the rat. J Comp Neurol. 1975 Jan 15 159(2):149-75 DOI: 10.1002/cne.901590202 AND Guidi S et al., Postnatal neurogenesis in the dentate gyrus of the guinea pig. Hippocampus. 2005 15(3):285-301 DOI: 10.1002/hipo.20050PubMed ID1112911, 15515010
||Primary source Guidi et al. abstract: "Animals of different postnatal (P) ages received one or multiple injections of bromodeoxyuridine (BrdU), and the number of labeled cells in the dentate gyrus was counted after time intervals of 24 h or longer. The total granule cell number and the volume of the granule cell layer were evaluated in Nissl-stained brain sections from P1 and P30 animals. P1-P5 animals were treated with MK-801 to analyze the effect of NMDA [N-methyl-D-aspartate] receptor blockade on cell proliferation."
||P.427 right column 2nd paragraph: "This difference in the ability of young rats and guinea pigs to form persistent memories directly mirrors differences in DG [dentate gyrus] development between the two rodent species: Whereas ∼80% of granule cells are added to the DG in the first 2 wk after birth in the rat, only ∼20% of granule cells are added during the first postnatal month in the guinea pig (primary sources)."