Table 2.

Results of the single-factor logistic regression for the occurrence of A. baumannii.

	All categories		Dairy cows		Pen-floor fecal samples
Putative determining factor	p-value	nObs	p-value	nObs	p-value	nObs
Age of the animal	0.0002	422	n.s.
Category (dairy/beef/calf)	0.0003	422
Feeding of corn silage	0.00705	367	0.0270	266
Feeding of straw	0.0215	105	n.s.
Local use of 1st CEPH on farm level	n.s.		n.s.		0.0458	330
Sex of the animal	0.0028	422	n.s.
Systemic use of 3rd CEPH on farm level	0.0010	387	0.0040	255	0.0372	319
Systemic use of florfenicol on farm level	n.s.		0.0500	255	n.s.
Systemic use of penicillin on farm level	0.0369	387	n.s.		n.s.
Trimester	<0.0001	422	<0.0001	280	0.0004	353
Use of sewage sludge	<0.0001	263	0.0013	169	0.0173	210

nObs, number of observations; 3rd CEPH, 3rd generation cephalosporins; 1st CEPH, 1st generation cephalosporins; n.s., not significant.