Adverse effects of Influenza A(H1N1)pdm09 virus infection on growth performance of Norwegian pigs - a longitudinal study at a boar testing station

Table 1 Akaike information criterion (AIC) and the parsimony principle were used to select the best model for each outcome

Outcome	Predictors (fixed effects)							Random effects		AIC	ΔAIC
Outcome	Infection status group (INFGP)	Breed (Br)	Growth Phase (GF)	Birthdate	Ave daily feed intake (ADFI)	Interaction term INFGP*GF	Interaction term INFGP*Br	Pig	Herd	AIC	ΔAIC
ADG	x	x	x	x	x	x	x	x	x	-7157.8	-1.7
	x	x	x	x	x	x	x		x	-7132.5	23.6
	x	x	x	x	x	x	x	x		-7147.8	8.3
→	x	x	x	x	x	x		x	x	-7156.1	0
	x	x	x	x	x		x	x	x	-7150	6.1
	x	x	x	x	x			x	x	-7149	7.1
FCE	x	x	x	x	x	x	x	x	x	-1889	3.7
	x	x	x	x	x	x	x		x	-1769	123.7
	x	x	x	x	x	x	x	x		-1878	14.7
→	x	x	x	x	x	x		x	x	-1892.7	0
	x	x	x	x	x		x	x	x	-1864	28.7
	x	x	x	x	x			x	x	-1867	25.7
ADFI	x	x	x	x	x	x	x	x	x	3299.8	2.8
	x	x	x	x	x	x	x		x	3564	267
	x	x	x	x	x	x	x	x		3307	10
→	x	x	x	x	x	x		x	x	3297	0
	x	x	x	x	x		x	x	x	3304	7
	x	x	x	x	x			x	x	3302	5
Age 100 kg	x	x		x	x		x		x	13111	5
	x	x		x	x		x			13205.5	99.5
→	x	x		x	x				x	13106	0
OFI	x	x		x	x		x		x	15281	3
	x	x		x	x		x			15362	84
→	x	x		x	x				x	15278	0

Abbreviations: ADG average daily growth in kg/day, FCE feed conversion efficiency in kg feed/kg weight gain, ADFI average daily feed intake in kg/day, Age 100 kg age of pig when they reached 100 kg, OFI overall feed intake in kg from 33 kg to 100 kg bodyweight.
Selected model is indicated by (→). Marking X indicates predictor was included in the model. ΔAIC = difference in AIC between the tested models and the selected model given in bold.

ISSN: 1746-6148