1. Introduction
Livestock forms an important component of the livelihoods of majority of developing
countries’ rural populations and are closely associated with the social fabric and welfare of
rural households. These rural populations live in complex, diverse and risk-prone
environments where livestock are mainly raised in low-input systems and perform multi-
faceted functions ranging from income, non-income to socio-cultural functions (Anderson,
2003). In African rural areas, livestock is an important source of food and cash, crucial for the
purchase of consumer goods and procurement of farm inputs. In addition, they are a means of
demonstrating wealth, storing savings and act as substitutes for missing financial and
insurance markets in developing countries (Moll, 2005).
Despite the high significance of livestock production in developing countries,
productivity remains low. In sub-Saharan Africa as in other developing countries, livestock
producers continue to face a number of technical, institutional and infrastructural constraints
related to feeding, animal health and genotype, leading to low livestock productivity levels.
The severity of these constraints varies by the various production systems under which
livestock production takes place. The production systems are determined by agro-ecology and
commonly differ in exhibiting various stress factors, such as water shortages, disease and
parasites as well as temperature extremes. In order for improved livestock productivity to be
realized, there is need to overcome or minimize the constraints faced by livestock keepers.
Animal diseases, especially those caused by parasites, are severe constraints on animal
production in sub-Saharan Africa. Trypanosomosis is arguably one of the most important of
these, with effects hardest felt by poor livestock keepers in sub-Saharan Africa.
Trypanosomosis is endemic in seven million square kilometers of Africa, comprising more
than one third of the land area across Africa. It is one of the major constraints of livestock
productivity, with forty six million cattle at constant risk of infection (FAO, 1991; Kristjanson
et al., 1999). The disease represents a major constraint to increased food production as it