Table 2.

Variables with p-values less than 0.2 in the univariable analysis comparing 56 BNP-case farms with two sets of 50 control farms in a study on BNP in southern Germany (2008–2010) (p-values ≤ 0.05 are indicated in bold).

Variable	Case farms (n = 56)	Set 1 control farms (n = 50)	Univariate p-value (control set 1)	Set 2 control farms (n = 50)	Univariate p-value (control set 2)
General information on the farm
Number of breeding young stock	Median 29.5	Median 40.0	0.039a	Median 30	0.441a
Number of calves	Median 20	Median 15	0.166a	Median 18.5	0.692a
Purchase of cattle	2/56	10/50	0.018	7/50	0.054
Free stall (cows)	25/55	33/50	0.034	30/50	0.114
Free stall (heifers)	31/55	19/50	0.059	30/50	0.629
Heifers in same barn as lactating cows	20/55	25/50	0.158	21/50	0.507
Dry cows and lactating cows in same barn	39/56	37/50	0.619	41/50	0.140
Calves housed in groups	47/56	39/50	0.436	47/50	0.102
Components of the cows’ ration
Barley	32/56	39/50	0.022	29/50	0.929
Rape	32/56	36/50	0.111	42/50	0.003
Linseed meal	10/56	0/50	0.001	10/50	0.778
Sugar beet pulp	19/56	8/50	0.034	12/50	0.190
Grass silage	55/56	45/50	0.098	50/50	0.342
Fresh grass	19/56	9/50	0.063	21/50	0.392
Clover	11/56	4/50	0.086	9/50	0.829
Maize (Corn)	40/56	27/50	0.063	31/50	0.303
Soybean	43/56	36/50	0.057	35/15	0.429
Brewer's grains	6/56	6/50	0.835	10/50	0.182
Hay	53/56	36/50	0.001	43/50	0.129
Straw	24/56	39/50	<0.001	16/50	0.250
Propylene glycol	21/56	8/50	0.013	7/50	0.006
Glycerol	9/56	7/50	0.766	3/50	0.102
Feeding of calves
Hay	49/56	50/50	0.014	50/50	0.010
Water free choice	49/56	50/50	0.014	49/50	0.063
Oral rehydration solutions	50/56	40/50	0.182	46/50	0.746
Colostrum replacerb	9/56	2/50	0.041	1/50	0.013
Concentrates	41/56	43/50	0.105	29/50	0.099
Prophylactic measures
Prophylactic use of Halofuginone	11/56	3/50	0.038	5/50	0.166
Vaccination of dams against calf diarrhoea	32/56	17/50	0.018	20/50	0.052
Oral vaccination of calves	3/56	3/50	0.886	0/50	0.097
Other prophylactic measures (e.g. parasitic, insect, other vaccinations)	20/56	14/50	0.395	4/50	0.002
Vitamin E/selenium	6/56	7/50	0.607	12/49	0.062
Vaccination against BVD	55/56	16/50	<0.001	17/50	<0.001
PregSure® BVDc	55/55	2/16	<0.001	13/17	<0.001
Prophylactic and therapeutic interventions in cows
Teat dips	14/56	24/50	0.014	14/50	0.680
Mastitis tubes	29/56	38/50	0.010	45/50	0.001
Dry cow mastitis treatment	43/56	45/50	0.070	42/49	0.245
Frequent calf diseases
Diarrhoea	29/56	14/50	0.013	19/50	0.182
Bronchopneumonia	19/56	6/50	0.008	13//50	0.411
Infectious agents (E. coli, rotavirus, coronavirus) identified	15/56	6/50	0.056	15/49	0.665
Inappetence	1/56	1/50	0.935	5/50	0.064
Miscellaneous
Use of stem growth regulators	12/56	33/50	<0.001	37/50	<0.001
BVD status (vaccinated/free/unknown)	55/0/1 (56)	16/10/24 (50)	<0.001	17/2/31	<0.001
Disinfection of calf buckets	5/56	10/50	0.102	4/49	0.889
Insect control	36/56	38/50	0.190	27/49	0.338
No access to sweet clover, horse tail and bracken fern	52/56	47/50	0.813	50/50	0.054

^aAssessed using Mann–Whitney U-test.

^bSome case farms had changed to use colostrums replacer after having had BNP cases, therefore this variable is biased.

^cNumber of farms that used PregSure^® BVD of those farms that vaccinated against BVD. Farms were classified as using PregSure^® BVD vaccine even if not all animals were vaccinated, as the variable was on herd level. For the multivariable analysis this variable was recoded into a new variable using PregSure^® yes/no for all 50 and 56 farms, respectively.