Abstract:
Background: Animal trypanosomosis is a major cause of economic loss in
livestock production in Africa. A suggested control measure is to use
breeds with traits of trypanotolerance. The study examines the effect of
natural Trypanosoma vivax challenge on haematological parameters in two
trypanotolerant cattle [N’Dama and West African Shorthorn (WASH)] herds.
Methods: Trypanosoma vivax-specific primers were used to diagnose T.
vivax infection in an N’Dama herd at Cape Coast in southern Ghana and a
WASH herd at Chegbani in northern Ghana from May to July 2011 in a
cross-sectional study. Levels of haematological parameters comprising
packed cell volume (PCV), haemoglobin (Hb) concentration and red blood
cell (RBC) and total white blood cell (TWBC) counts; differential WBC
counts (neutrophils, lymphocytes, eosinophils, monocytes and basophils);
and RBC indices of mean corpuscular volume (MCV), mean corpuscular
haemoglobin (MCH) and mean corpuscular haemoglobin concentration
(MCHC) were determined in blood samples and then compared between
infected and uninfected cattle.
Results: We found that haematological indices for infected and uninfected
animals in both breeds were within the normal range. However, the mean
PCV values for T. vivax-infected WASH and N’Dama were lower in infected
compared to uninfected animals. The difference was significant ( p< 0.05)
in N’Dama but not in WASH.
Conclusion: Despite the presence of infection by T. vivax, N’Dama and
WASH cattle maintained their haematological parameters within acceptable
normal ranges, which confirms their trypanotolerant trait. This highlights the
need for low-input traditional African farmers in medium, high and severe
tsetse challenge areas to be educated on the advantages of N’Dama and
WASH breeds to increase their utilization in integrated tsetse and
trypanosomosis control programmes.
