Table 5.

Summary of estimated pooled Toxoplasma gondii seroprevalence and heterogeneity measures by age groups (young ≤1 year, old >1 year) in domestic pigs, sheep, wild boars and moose using mixed effects model as part of a systematic review for the Nordic and Baltic countries.

Host species	Age group	No. of positive animals	Total no. of animals	Pooled seroprevalence (%) (95% CI)	Heterogeneity			Statistical effect of age	Study [reference]
					Q	Q-P	I2 (%)	P-value
Domestic piga	Young	181	5048	4.0 (2.0–6.3)	69.6	<0.01	90.0	<0.0001	Lind et al., 1994; Lundén et al., 2002; Deksne, 2010; Felin et al., 2015; Wallander et al., 2016; Kofoed et al., 2017; Santoro et al., 2017; Felin et al., 2019
	Old	138	802	18.1 (12.0–25.2)	32.8	<0.01	91.0		Lind et al., 1994; Lundén et al., 2002; Kofoed et al., 2017; Santoro et al., 2017
Sheepb	Young	337	2142	13.1 (5.6–23.0)	3.9	0.14	49.0	0.04	Skjerve et al., 1998; Deksne et al., 2017; Tagel et al., 2019
	Old	1275	4324	27.8 (17.9–38.9)	188.4	<0.01	99.0		Jokelainen et al., 2010; Deksne et al., 2017; Tagel et al., 2019
Wild boarc	Young	142	493	25.7 (16.0–36.7)	10.2	0.02	71.0	0.10	Jokelainen et al., 2012; Jokelainen et al., 2015; Wallander et al., 2015; Laforet et al., 2019
	Old	242	617	38.4 (28.0–49.4)	35.3	<0.01	91.0		Jokelainen et al., 2012; Jokelainen et al., 2015; Wallander et al., 2015; Laforet et al., 2019
Moosed	Young	86	1326	8.3 (4.0–14.0)	46.3	<0.001	85.0	0.01	Vikøren et al., 2004; Jokelainen et al., 2010; Malmsten et al., 2011; Remes et al., 2018
	Old	482	2808	19.4 (13.0–26.7)	20.5	<0.001	94.0		Vikøren et al., 2004; Jokelainen et al., 2010; Malmsten et al., 2011; Remes et al., 2018

I² = Inverse variance index; Q = Cochran's Q test for heterogeneity; Q-P = probability value of Cochran's Q test for heterogeneity. a = Data extracted from eight studies as five studies did not report age in domestic pigs. In total, the age group of 6877 out of 12,727 animals was not reported. b = Data extracted from four studies as two studies did not report age in sheep. In total, the age group of 179 out of 6645 animals was not reported. c = Data extracted from four studies as two studies did not report age in wild boars. In total, the age group of 1868 out of 2978 animals not reported. d = Data extracted from all four studies reporting age group of the moose. In total, the age of 103 out of 4237 animals was not reported.