Data on the frequency, distribution and mean intensity of
the helminth fauna recovered from outbred and inbred mice conventionally
maintained in Brazilian animal houses, are reported. The oxyurid nematodes
presented overall frequencies of 91.5% and 8.5%, respectively. The frequency
in animals of three groups out of the four investigated ranged from 9% to
from 17% to 83%, since animals of one of the groups were negative for helminths.
Infections due to a single species were observed in 62% of the animals,
compared to 16% related to associations. The frequency of single infections
in each group varied from 58.6% to 100% whereas associations varied from
24.1% to 41.4%. The analysis of specific mean intensities showed that S.
obvelata was represented by 13.35 to 66.58 specimens/host and
by 5.85 to 16.75 specimens/host.