Table 1.

Background information collected by interviewing four dairy herd owners before the herds were enrolled in a study on the effect of hydrated lime on cryptosporidiosis.

	Herd 1	Herd 2	Herd 3		Herd 4
Herd size (No of cows)	332	222	150		165
Mean annual milk production (ECM)	11960	9156	9000		10381
Time calves spend with their dam (hours)	<5	4-12	24		5–12
Volume of first meal of colostrum (L)	2-4	4-5	2.5-3		3
Volume of additional colostrum meals on day of birth (L)	5	5-6	3		3
Period of feeding of colostrum or transition milk (days)	>4	4	4		1.5–2
Type of individual calf housing	Pens indoors	Pens indoors and huts outdoors	Huts outdoors		Pens indoors
Age when calves move to group pens (weeks)	1-2	2-3	1-2		3–4
Interval between cleaning of individual pens or huts	between each calf	between each calf	between each calf		every 7–9 day
Empty period before introduction of new calf (days)	2-3	2-3	7		< 1
Washing individual pens or huts with water	briefly between each calf	1-2 times/year	between each calf		1-2 times/year
Drying period after washing with water	2-3 days	2-3 days	4-5 days		1 week
Yearly washing of individual pens or huts	yes	no	yes		yes
Calf mortality 1-60 days – median previous 12 months (%)	4.2	0.6	7.6		8.0
Calf diarrhea during the previous 6 months
Morbidity (%)	100	33-50		50	50
Proportion of calves with affected appetite or general condition (%)	5-10	10		>25	>25
Duration of diarrhea problem	14 years	several years		several years	several years
Where the calves develop diarrhea	individual pens	individual pens		Individual pens not individual huts	calving pen
Age when calves develop diarrhea	2-10 days	1.5-2 weeks		0-2 weeks	0-2 weeks