Slov Vet Res 2007; 44 (1/2) - Slovenian veterinary research

The source of contamination of ground meat for production of meat products with bacteria Staphylococcus aureus
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meat in an inadequate environment for a longer
period of time could enhance the growth of bacteria
and production of enterotoxins, especially in meat
products that are not subject to a bactericidal process.
Animal biotypes were isolated from workers in
the slaughterhouse. Humans could act as a reservoir
for both human and animal biotypes (8).
For differentiation of separate strains of bacteria
S. aureus we used the RAPD-PCR method. We
proved a correlation between beef carcasses, hand
equipment and ground meat, and we established
differences in RAPD-PCR patterns between isolated
strains of S. aureus from human and animal origin.
In the slaughterhouse we isolated both types of
strains from workers hands, equipment beef carcass
and ground meat .
These findings support the results of other studies,
that coagulase positive staphylococci isolated
from workers in slaughterhouses have similar phage
patterns to strains isolated from meat products (3).
According to the findings from our study the
hands of workers are a source of contamination of
the surface of beef carcasses with bacteria S. aureus.
The surface of carcasses frequently is comes
into contact with hands during operations on the
slaughter line.
The contaminated surface of beef carcasses is
crucial for contamination of ground meat as the
meat goes to grinding. To prevent the contamination
of carcasses it is essential that the incidence and
counts of S. aureus be reduced. To achieve this, more
care needs to be exercised in removing the hide, and
viscera, and in carefully trimming the surface of carcasses
prior to chilling. Washing of the carcass may
have resulted in redistribution of the contamination
(3). It is also important, according to our findings,
to avoid contact between meat and the hands of
workers. Several studies have shown that elimination
of carriage in the anterior nares, the principal
reservoirs of S. aureus, reduces the incidence of S.
aureus infection (9). Because the surfaces of beef
are contaminated with the same type of S. aureus
as the arms of workers, establishing contamination
of the surface of beef carcasses with S. aureus on
the slaughtering line can be the indicator of work
hygiene among workers on the slaughtering line.
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