Potential risk factors for the presence of anti-Toxoplasma gondii antibodies in finishing pigs on conventional farms in the Netherlands

Table 3 Multivariable analysis of potential risk factors for T. gondii infection in finishing pigs from 69 Dutch finishing pig farms using backward elimination and inclusion criterion of P ≤ 0.05

Risk factor	No. of Farms	Blood samples			OR	95% CI	P-value
Variables		No. positive	No. tested	Avg. % pos.*
Type of farm
Closed	14	42	1180	6.1%	1.00		0.0488
Open	55	217	3954	7.2%	0.63	0.40–1.00
Dogs
Absent	22	83	1211	9.6%	1.00		0.0161
Present	47	176	3923	5.7%	0.60	0.40–0.91
Ruminants (cattle, sheep and/or goat)
Absent	41	145	3463	5.4%	1.00		0.0071
Present	28	114	1671	9.1%	1.67	1.15–2.42
Boots only used inside stables
No	43	207	3578	8.7%	1.00		0.0068
Yes	26	52	1556	4.0%	1.91	1.20–3.04
Shower and farm clothing
No	61	235	3947	7.3%	1.00		0.0106
Yes	8	24	1187	4.3%	0.37	0.17–0.79
Mode of rodent control
No or only with traps	4	12	262	4.0%	1.00		0.0056
Poison	47	175	3808	6.5%	3.37	1.23–9.23
Poison and traps	18	72	1064	14.1%	5.57	1.90–16.3
Bedding pigs accessible for rodents
No	64	253	4767	7.1%	1.00		0.0002
Yes	5	6	367	5.1%	0.17	0.07–0.44
Presence of cats
Absent	19	47	1530	5.1%	1.00		< 0.0001
Present, no kittens, no stable access	29	82	2498	4.2%	1.90	1.11–3.27
Present, kittens, cats not in stable	11	82	697	9.9%	11.80	6.23–22.5
Present, no kittens, stable accessible	3	7	99	5.7%	2.87	0.67–12.3
Present, kittens, stable accessible	6	41	304	21.3%	4.20	2.04–8.55
Drinking water for pigs
Tapwater	32	96	1555	7.3%	1.00		0.0095
Well	37	163	3579	6.7%	0.60	0.40–0.88
Feed heated
No	37	195	3459	9.2%	1.00		0.0129
Yes	32	64	1675	4.3%	0.42	0.21–0.83
Whey (goat)
No	65	201	4887	5.0%	1.00		< 0.0001
Yes	4	58	247	37.6%	11.30	7.12–18.0
Shielding of birds
No	8	26	316	9.1%	1.00		0.0035
Yes	61	233	4818	6.7%	0.18	0.06–0.57

ISSN: 2055-5660