A case of bovine mastitis caused by Bacillus cereus.

Abstract Although the cause of most bovine mastitis can be attributed to the major pathogens of the udder (Staphylococcus spp., Streptococcus spp. and Escherichia coli), occasional cases occur that are caused by more unusual organisms. The mastitis caused by a number of these organisms may be characterised by a very marked degree of tissue damage and, consequently, grossly abnormal mammary secretions. Notable amongst such organisms is Bacillus cereus, for which a number of cases have been reported from many countries with significant dairy industries (Scheifer et al., 1976; Jones and Turnbull, 1981). In a British survey, B. cereus mastitis accounted for 0.3% of cases (Johnson, 1986), whilst in the Sydney region of Australia, 119 cows were diagnosed with B. cereus mastitis between 1960 and 1985 (Johnson, 1986). However, no previous case reports have been found for cattle in New Zealand, although it is isolated from time to time in routine culture of milk from cows with inexplicably high somatic cell counts...