Table 1.

Distribution of disease events according to categorical variables potentially associated with the odds of veterinary treatment for young animal and cows, respectively.

Variables	Categories	No. of herds	No. of events	Veterinary treatment
				No.	%
Young animals:
Herd level
Average SCC in test-milk	< 170	11	96	20	21
	170–196	4	42	7	17
	196.1–236	9	69	27	39
	> 236	4	36	14	39
Average udder disease score a	< 2.4	7	74	22	30
	2.4–2.6	7	47	12	26
	2.61–2.7	4	38	7	18
	> 2.7	10	84	27	32
Main breed	Swedish Red	10	74	11	15
	Swedish Holstein	18	169	57	34
Good record-keeping ability	Yes	24	217	53	24
	No	4	26	15	58
Participation	Only January	2	11	5	45
	All months	26	232	63	27
Veterinary district	Private	11	84	16	19
	State-employed	17	159	52	33
Disease event level
Age	< 2 months	24	149	26	17
	2–15 months	17	54	14	26
	> 15 months	20	40	28	70
Study month	January	25	116	26	22
	April	16	37	14	38
	July	18	45	11	24
	October	19	45	17	38
Breed	Swedish Red	15	65	6	9
	SH	23	167	57	34
	Mixed/Other	6	11	5	45
Disease	Cough	12	52	17	33
	Gastro-intestinal disorders	22	96	7	7
	Lameness disorders	14	28	19	68
	Other disorders	17	67	25	37
Cows:
Herd level
Main Breed	Swedish Red	60	617	387	63
	Swedish Holstein	65	913	689	75
	Mixed/Other	15	177	123	69
Housing type	Tied	107	1,066	721	68
	Warm loose	27	175	382	218
	Cold loose	6	466	96	21
Proportion of cows above third lactation	< 0.14	35	429	302	70
	0.14–0.179	26	416	267	64
	0.18–0.24	39	430	313	73
	> 0.24	40	432	317	73
Disease event level
Another animal with an event at the same date	Yes	118	726	594	82
	No	140	981	605	62
Breed	Swedish Red	105	633	404	64
	Swedish Holstein	113	996	742	74
	Other	35	78	53	68
Culled	Not culled	129	690	510	74
	≤ 305 days after event	136	736	505	69
	> 305 days after event	115	281	184	65
Days in milk	< 7	125	394	318	81
	7–69	126	450	327	73
	70–168	125	435	292	67
	> 168	119	428	262	61
Disease complex	Lameness disorders	90	316	166	53
	Metabolic disorders	112	260	200	77
	Other disorders	78	144	111	77
	Peripartum disorders	77	124	96	77
	Udder disorders	138	863	626	73
Study month	January	128	519	317	61
	April	120	353	227	64
	July	111	436	349	80
	October	116	399	306	77
Pregnant	Yes	91	237	161	68
	No	140	1,470	1,038	71
Reason for culling	Not culled	129	691	510	74
	Milk	56	102	60	59
	Udder	121	405	281	69
	Other	128	509	348	68

^a The udder disease score is used to measure the probability of a cow having mastitis and is based upon a series of three monthly test day SCC results for the individual-cow [13].