The sensitivity of the culture method used may be influenced by
the numbers of viable organisms present and
long incubation times can result in overgrowth of B. abortus by
contaminants, although the addition of antibiotics to growth media
are effective in reducing contamination. Pre-enrichment
in liquid medium increases the sensitivity of culturebut liquid culture can also increase
the risk of contamination when collection
and transport conditions are less than ideal and when larger quantities
of tissue are inoculated