Culling in served females and farrowed sows at consecutive parities in Spanish pig herds

Table 4 Model selection for two-level mixed-effects log-binomial regression models for served sows

	Model specification				pseudo-AIC
Model for culling risk of served sows
	Fixed effect^a,b			Random effect	Consecutive parities
Model No.	HG	WSI	Interaction	Herds	1	2	3	4	5	6
			HG × WSI	Herds	1	2	3	4	5	6
1	✓			✓	31,377	26,055	25,598	23,283	21,565	16,510
2		✓		✓	31207^c	25,890	25,462	23,158	21,491	16,469
3	✓	✓	✓	✓	31,209	25887^c	25,464	23,154	21,489	16,465
4	✓	✓		✓	31,209	25,889	25462^c	23154^c	21489^c	16463^c
COVTEST for final Model					<0.01	<0.01	<0.01	<0.01	<0.01	<0.01

HG herd groups, WSI weaning-to-first-service interval
^aEntry years were included into all models
^bThe univariate models were not shown because the AIC were higher than those shown in Models 1 and 2
^cFinal model is selected by the lowest pseudo-AIC

ISSN: 2055-5660