A bacteriological study was performed on 226 semen samples from healthy boars collected from five pig farms in two Venezuelan states. The evaluation of fresh and diluted semen showed a wide variety of bacteria range from normal and potentially pathogenic flora. E. coli
was the most common bacteria isolated, followed by Staphylococcus epidermidis
, Proteus vulgaris
spp. β hemolytic
, Staphylococcus aureus
and Psedomonas aeruginosa
. The bacteria were found to be resistant to the antimicrobials normally used in commercial diluents semen.