Abstract

In an effort to further elucidate the possible effect of trypanosome infection on serum levels of some lipids and cholesterol, five sheep (the infected group) were each intravenously inoculated with 2 ml of blood containing 1 x 10⁶ Trypanosoma congolense organisms. Another five uninfected sheep served as control group. Blood samples were collected from all the animals every other day from the day of infection (day 0) up to the termination of the experiment. The samples were used for haematological and parasitological analyses and determination of serum concentrations of total cholesterol, triglycerides, high density lipoprotein-cholesterol (HDL-cholesterol) and low density lipoprotein-cholesterol (LDL-cholesterol). All animals in the infected group showed parasitaemia by day 11 post-infection (PI) and the infection caused a gradual decline in the values of packed cell volume (PCV) and those of serum total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol. Values of all these parameters in the control group remained fairly normal, relative to the pre-infection ones on day 0, throughout the experimental period. The PI mean values of serum total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol, measured in mmol/l, in the infected group were 3.44 ± 0.71, 1.62 ± 0.40, 0.78 ± 0.20 and 1.92 ± 0.40, respectively, while those in the control group were 4.32 ± 0.18, 2.24 ± 0.11, 1.15 ± 0.10 and 2.26 ± 0.30, respectively. The differences between the PI mean values in the two groups of animals were significant (P<0.05). T. congolense utilization of the molecules could, among other factors, be the cause of the reduced serum levels of these parameters and this could be a contributory factor in the pathophysiology of some of the disorders observed in trypanosome-infected animals.

Key words: Trypanosomosis, sheep, cholesterol, triglycerides, low density lipoprotein, high density lipoprotein.