. Author manuscript; available in PMC: 2019 Feb 1.

Published in final edited form as: Behav Brain Res. 2018 Nov 1;359:172–180. doi: 10.1016/j.bbr.2018.10.040

Table 1.

Overview of the housing conditions. (*) Two of these rats (1 of each cage) were used for pilot testing after PND 58 (data not shown). Note that although the surface area per rat was larger for IH than for the other housing conditions, the total space to move for the IH animals was compromised due to the low height of the cages.

Properties	Enriched housing (EH) (n = 16) PND 26 – end	Standard housing (SH) (n = 18*)		Impoverished housing (IH) (n = 16) PND 26 – end

		PND 26 – PND 58	PND 58 – end
# rats/cage	4	9*	4	1
Cage size	60 × 40 × 18.5 cm	60 × 40 × 18.5 cm	43 × 28.5 × 18.5 cm	27 × 17 × 11.5 cm
Surface area/rat	600 cm²	267 cm²	306 cm²	459 cm²
Bedding material	Yes	Yes	Yes	Limited amount (V = 250 ml, covering 85% of the floor)
Enrichment	3 tunnels, paper shred, and several toys that were changed regularly	No	No	No