Plasma lipopolysaccharide elevations in cattle associated with early-stage infection by Fasciola hepatica

Abstract

<p>Fasciolosis is an endemic zoonotic parasitic disease with significant impacts on human health and both animal health and production. Early post-infection impacts on the host remain unclear. The objective of this study was to determine the changes, if any, to levels of endotoxin in cattle plasma in response to early-stage infection with <i>Fasciola</i> hepatica. Thirty-six (36) commercial bred cattle were experimentally infected with approximately 400 viable metacercariae. Plasma lipopolysaccharide (endotoxin) levels were examined on 24 occasions from 0 h before infection to 336 h after infection using the Limulus Amoebocyte Lysate chromo-genic end point assay and compared with that of six (6) uninfected control animals. Peak lipopolysaccharide levels in infected animals were reached at 52 h after infection and returned to pre-infection levels at time 144 h after infection. Infected animals had significantly elevated lipopolysaccharide levels between 24 and120 h after infection when compared to uninfected animals. The mean change in endotoxin units (EU)/mL over time after infection was statistically significant in infected animals. Elevations of lipo-polysaccharide occurred in all infected animals suggesting a possible repeatable and titratable endotoxemia conducive to therapeutic agent model development.</p>