Serum transaminase levels in cattle and sheep Infected with Trypanosoma vivax

Abstract

Glutamic-pyruvic transaminase (GPT) and glutamic-oxaloacetic transaminase (GOT) levels were determined in sera from uninfected West African zebu cattle and dwarf sheep, and from animals infected with Trypanosoma vivax transmitted by tsetse fly. Serum GPT levels in infected animals were normal during the prepatent periods; when trypanosomes were present in the peripheral blood, they increased and varied with the number of parasites and they returned to normal after therapeutic treatment. In infected cattle the increase in the mean serum GPT level was 2-fold and in sheep it varied up to 10-fold. Only small increases of serum GOT activity occurred. Homogenates of T. vivax contained high levels of GPT and GOT in an approximate proportion of 5:1; homogenates contained 100–200 times more GPT and 10 times more GOT than equal volumes of normal sera. Induced hepatic necrosis in sheep was accompanied by 3–10-fold increases in serum GOT activity but GPT activity remained normal. It seems probable that in T. vivax infections the abnormal levels of serum transaminase activity result from the destruction of trypanosomes and not from pathological effects of the parasites on the tissues of the host.