an epidemiological study of listeriosis in dairy cattle

) Duration of housing: If animals were housed farmers were asked to specify the
months between which animals were kept in. This variable was categorised as less than
6 months, 6 months, more than 6 months or all year around.
c) Type of floor: The farmers were asked to specify the type of floor of any building,
used to house cattle, from the following list; earth, hard core, concrete, slatted and
others. These were used as binary variables.
d) Use and type of bedding: Farmers were asked if they used bedding and this was used
as a binary variable. They were also asked to select given options; sawdust, straw or
specify other types of bedding material used on their farms. These were treated as
binary variables. Frequency of weekly adding and removing fresh bedding to and the
frequency of cleaning out bedding from the house over the housing period was also
used first as a binary variable and then as a categorical variable.
e) Straw bedding: If straw was used for bedding, the farmers were asked about the
month of making straw (categorical), duration of drying it (categorical), type (barley,
wheat, etc.) (binary) and whether it was big bale or others (binary).
f) Storage of bedding materials: The method of storing bedding was investigated by
asking farmers to identify the method(s) of storage from the followings; storing in a
covered barn, outside covered, outside uncovered and others.
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