Iron status in piglets at three days of age and at weaning and possible seasonal effects on the blood haemoglobin levels in a Swedish outdoor pig-producing farm

Table 4 Final mixed linear regression model for haemoglobin concentration at day three after birth

Variable	Level	Estimate	Standard error	Overall P-value
Intercept		91.8	8.2
Season	spring	-12.6^a	5.4	< 0.001
	summer	0.0^b	Ref
	autumn	15.9^c	5.64
	winter	-2.2^b	5.5
Parity	1	2.7	4.0	0.563
	2	0.0	Ref
	3	5.1	4.0
	≥ 4	-0.9	3.7
Time of day, parturition	morning	-10.6	9.0	0.728
	day	-2.7	9.2
	evening	1.3	3.6
	night	0.0	Ref
	not known	3.7	6.0
Gender	male	0.8	1.2	0.501
	female	0.0	Ref
Number of live born piglets		-0.3	0.5	0.483

^abc Estimates within levels of variables with different superscripts are statistically significant different. Ref indicates the reference level for each variable

ISSN: 1751-0147