This study was carried out in order to quantify enteric bacteria and identify the presence of Salmonella
spp., Escherichia coli, Clostridium perfringens and Erysipelothix rhusiopathiae in the liquid fraction of excreta
generated from a small scale swine farm by means of a primary treatment system, consisting of the separation
of solids and the sedimentation of liquids. Samples were collected at the following stages of the
treatment: collection basin (CB), liquid obtained from a solids separator (SLF) and liquid from the
sedimentation basin (SB). In each sample, enteric bacteria (cfu/g wet weight) and E. coli were quantified,
Salmonella spp. was isolated and typified, and C. perfringens, and E. rhusiopathiae were isolated. No significant
differences (p > 0.05) were found in the enteric bacteria and E. coli population levels at any treatment
stage. S. choleraesuis was found in 20% of CB samples analyzed, 40% of SLF samples and 30% of SB
samples. C. perfringens was isolated from SLF and SB. E. rhusiopathiae was not isolated (below the
minimum detection limit). Results suggest that primary treatment does not reduce the amount of enteric
bacteria, or eliminate Salmonella spp., E. coli and C. perfringens. Therefore, it is necessary to apply
additional treatments to allow safe use of the liquid obtained in the farm.