Table 5.

Cow factors with significant (P < 0.10) effect on prevalence of subclinical mastitis (SCC ≥200 000/ml) or intramammary infections (IMI) in beef cows examined within one month after calving in 10 beef cow herds

Outcome	Cow factor	Class	Number of cows with different numbers of quarters affected (QA)			Total numbers P-values
Quarters with SCC ≥200 000/ml			0 QA	1 QA	≥2 QA
	Breed	Hereford	23	12	0	35
		Cross bred	8	5	4	17
		Limousin	12	3	6	21
		Simmental	12	9	8	29
		Total	55	29	18	P = 0.008
	Teat shape	Normal	37	12	8	57
		Large funnel-shaped	16	15	10	41
		Total	53	27	18	P = 0.038
	Udder shape	Normal	48	17	15	80
		Pendulous	7	12	3	22
		Total	55	29	18	P = 0.012
Quarters with CMTa ≥3			0 QA	1-4 QA
	Teat shape	Normal	52	5		57
		Large funnel-shaped	27	14		41
		Total	79	19		P = 0.004
	Udder shape	Normal	68	12		80
		Pendulous	14	8		22
		Total	82	20		P = 0.035
Quarters with any IMI			0 QA	1 QA	≥2 QA
	Parity	1	22	6	1	29
		2	13	2	3	18
		3	6	7	3	16
		4	8	7	0	15
		5-6	8	5	3	16
		≥7	4	3	1	8
		Total	61	30	11	P = 0.083
	Teat shape	Normal	39	13	5	57
		Large funnel-shaped	19	16	6	41
		Total	58	29	11	P = 0.094
	Blind quarter present	No	58	25	8	91
		Yes	3	5	3	11
		Total	61	30	11	P = 0.031
Quarters with any major IMI			0 QA	1 QA	≥2 QA
	Blind quarter present	No	77	11	3	91
		Yes	6	3	2	11
		Total	83	14	5	P = 0.025
Quarters with CNSb IMI			0 QA	≥1 QA
	Hygiene	1	15	1		16
		2	43	21		64
		3-4	18	3		3
		Total	76	25		P = 0.048
Quarters with S. aureus IMI			0 QA	≥1 QA
	Blind quarter present	No	80	11		91
		Yes	7	4		11
		Total	87	15		P = 0.054

^aCMT = California Mastitis Test.

^bCNS = coagulase negative staphylococci.