Serum Total and Lipid-Bound Sialic Acid Concentrations in Sheep With Natural Babesiosis

Abstract

The aim of this study was to determine the serum concentrations of total and lipid-bound sialic acid in sheep naturally infected with Babesia ovis before and after treatment. Thirty diseased sheep and ten control animals were used. Babesia infection was confirmed with Giemsa's staining of blood smears. Compared to the control animals (1.351 +/- 0.100 mmol center dot l(-1); 0.385 +/- 0.001 mmol center dot l(-1)), a marked increase of serum total and lipid bound sialic acid concentrations (1.929 +/- 0.101 mmol center dot l(-1); 0.479 +/- 0.004 mmol center dot l(-1), respectively) was obtained in infected sheep (p < 0.05). One week after treatment, serum total and lipid bound sialic acid concentrations significantly decreased (1.554 +/- 0.005 mmol center dot l(-1); 0.411 +/- 0.02 mmol center dot l(-1), respectively) (P < 0.05). Despite this decline, total and lipid bound sialic acid concentrations of treated animals were still significantly increased in sera compared to the control animals (p < 0.05). When the infected animals were treated with an antiparasitic drug (diminazene aceturate), the serum total and lipid bound sialic acid levels had a tendency to decrease to the normal ranges. It can be concluded that Babesia ovis infection induced marked and persistent elevations of serum total and lipid-bound sialic acid concentrations, suggesting that these indicators would indirectly promote the invasion and presence of the parasite in the host.