Leucocyte Apotosis in Bovine Trypanosomosis

Abstract

The involvement of peripheral blood leucocyte and splenocyte apoptosis in cattle naturally infected with trypanosomes was investigated by light microscopy. One hundred blood and twenty six spleen samples from the same animals were collected from the Bodija Municipal Abattoir in Ibadan, South-West Nigeria. Of the 100 blood samples collected, 12 were trypanosome positive while the rest were negative and showed no other haemoprotozoan parasite. In addition, none of the blood sample form these animals showed leucocyte apoptosis by light microscopy. However, Giemsa stained touch impression smear of the spleens revealed apoptotic splenocyte in both infected (6/12) and non-infected (3/14) cattle. Furthermore, there was a significant increase (P=0.041) in the number of apoptotic splenocyte in the infected compared with the non-infected control population. It was observed that, high parasitaemia was associated with high splenocyte apoptosis in cattle and the white Fulani breed showed more apoptotic splenocytes than other breeds sampled. Our study provides the first report of the occurrence of splenocyte apoptosis in cattle naturally infected with trypanosomes. We therefore suggest that leucocyte apoptosis may play an important role in the pathogenesis of the disease and may represent an essential factor in trypanosusceptibility.

Keywords: Trypanosomes, Apoptosis, Leucocytes, Splenocytes, Cattle.