. 2021 Apr 29;12:678054. doi: 10.3389/fphys.2021.678054

TABLE 2.

Least square means (LSM), their standard errors (SE) and significant differences between the levels of interaction effects for blood concentrations of total and ionized calcium, inorganic phosphate (PO4), the carboxyterminal crosslinked telopeptide of type I collagen (CTX-I), osteocalcin, 25-hydroxycholecalciferol (25(OH)D₃) and estradiol-17β of the blood of brown-(BLA) and white-egg (WLA) laying hens examined in the 25th, 29th, 49th and 69th week of age.

Effect		Total calcium (mmol/l)	Ionized calcium (mmol/l)	PO4 (mmol/l)	CTX-I (ng/ml)	Osteocalcin (ng/ml)	25(OH)D₃ (ng/ml)	Estradiol-17β (pg/ml)

		LSM ±SE	LSM ±SE	LSM ±SE	LSM ±SE	LSM ±SE	LSM ±SE	LSM ±SE
Layer line × Time of the day
BLA	6 a.m.	6.37^AB± 0.13	1.54^A± 0.03	1.70^B± 0.08	0.32^A± 0.07	20.67^A± 0.93	25.90^A± 1.13	405.65^ABC± 16.32
	10 a.m.	6.55^A± 0.13	1.26^C± 0.03	1.83^AB± 0.08	0.28^A± 0.07	15.39^B± 0.92	25.77^A± 1.13	405.50^ABC± 16.32
	2 p.m.	6.33^AB± 0.13	1.41^B± 0.03	1.87^AB± 0.08	0.13^A± 0.07	13.94^BC± 0.92	24.57^A± 1.13	373.42^BC± 16.32
	6 p.m.	5.87^BC± 0.13	1.32^BC± 0.03	1.97^AB± 0.08	0.32^A± 0.07	21.67^A± 0.92	22.78^A± 1.13	361.25^BC± 16.32
WLA	6 a.m.	6.27^AB± 0.13	1.44^AB± 0.03	1.76^B± 0.09	0.17^A± 0.07	11.75^BCD± 0.93	17.28^B± 1.19	456.95^A± 16.52
	10 a.m.	6.43^AB± 0.13	1.21^C± 0.03	1.70^B± 0.09	0.09^A± 0.07	9.65^D± 0.95	17.11^B± 1.19	414.12^AB± 16.52
	2 p.m.	5.99^ABC± 0.13	1.41^AB± 0.03	1.62^B± 0.09	0.07^A± 0.07	8.77^D± 0.93	16.30^B± 1.19	396.49^ABC± 16.52
	6 p.m.	5.64^C± 0.13	1.27^C± 0.03	2.17^A± 0.09	0.31^A± 0.07	11.19^CD± 0.93	13.49^B± 1.19	343.30^C± 16.52
Layer line × Age
BLA	25	4.95^D± 0.13	1.45^AB± 0.03	1.95^A± 0.08	0.21^AB± 0.07	20.73^A± 0.98	28.64^A± 1.25	257.87^F±20.78
	29	5.84^C± 0.13	1.21^C± 0.03	1.65^A± 0.08	0.45^A± 0.07	18.10^AB± 0.92	20.15^B± 1.14	339.41^DE±15.49
	49	7.10^A± 0.13	1.51^A± 0.03	1.88^A± 0.08	0.13^B± 0.07	16.18^B± 0.92	20.57^B± 1.25	415.34^BC±14.70
	69	7.24^A± 0.13	1.37^B± 0.03	1.89^A± 0.08	0.27^AB± 0.07	16.63^AB± 0.92	29.65^A± 0.88	533.19^A±14.70
WLA	25	4.80^D± 0.14	1.44^AB± 0.03	1.77^A± 0.08	0.25^AB± 0.07	14.31^B± 1.05	16.50^BC± 1.40	261.22^EF±23.24
	29	5.84^C± 0.13	1.05^C± 0.03	1.74^A± 0.08	0.18^AB± 0.07	8.97^C± 0.92	11.91^C± 1.25	371.32^CD±15.49
	49	6.43^B± 0.13	1.44^AB± 0.03	1.92^A± 0.08	0.10^B± 0.07	8.98^C± 0.92	16.37^BC± 1.25	457.68^B±14.70
	69	7.25^A± 0.12	1.42^AB± 0.03	1.82^A± 0.08	0.12^B± 0.07	9.07^C± 0.92	19.40^B± 1.88	520.64^A±13.42

^A–FMeans within a column and effect with no common superscript differ significantly at P < 0.05.