The aim of the present study was to compare the ability of the commercially available portable test system (PTS(TM)) to detect endotoxin activity in bovine serum, with that of the traditional LAL-kinetic turbidimetric (KT) and chromogenic (KC) assays. Prior to testing, serum samples, which were obtained from endotoxin-challenged cattle, were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. The performance of the PTS(TM) was not significantly different from that of the traditional LAL-based assays. The results using PTS(TM) correlated with those using KT (r(2)=0.963, P<0.001) or KC assays (r(2)=0.982, P<0.001). Based on these findings, the PTS(TM) could be applied as a simplified system to assess endotoxin activity in bovine serum.