Table 1.

Microvascular parameters such as vessel diameter, centerline blood flow velocity, and wall shear rate in the yolk sac at different days of gestation

Microvascular parameters	Embryonic day (fluorophore)
	13 (GFP)	14 (GFP)	15 (GFP)	16 (AO + GFP)	17 (AO + GFP)	18 (GFP)
Number of vessels	24	35	37	24	31	16
Diameter (μm)	56 ± 2	59 ± 2	53 ± 2	55 ± 3	48 ± 2	44 ± 3
Vmean (μm/s)	1100 ± 60	1000 ± 70	1000 ± 60	1200 ± 60	1100 ± 10	1000 ± 100
γ (s−1)	480 ± 30	420 ± 30	500 ± 30	570 ± 45	580 ± 55	590 ± 60