Impact of nutrition on the pathophysiology of bovine trypanosomiasis

Trypanosomiasis is a major veterinary problem over much of sub-Saharan Afri ca and is frequently associated with undernutrition. There is growing evide nce that nutrition can have a profound effect on the pathophysiological fea tures of animal trypanosomiasis. These features include anaemia, pyrexia, b ody weight changes, reduced feed intake and diminished productivity includi ng reduced draught work output, milk yield and reproductive capacity. Anaem ia is a principal characteristic of trypanosomiasis and the rate at which i t develops is influenced by both protein and energy intakes. Pyrexia is ass ociated with increased energy demands for maintenance which is ultimately m anifested by reductions in voluntary activity levels and productivity. Weig ht changes in trypanosomiasis are markedly influenced by the levels of prot ein intake. High intakes allow infected animals to grow at the same rate as uninfected controls providing energy intake is adequate whilst low energy levels can exacerbate the adverse effects of trypanosomiasis on body weight . Reductions in feed intake are less apparent in animals which are provided with high protein diets and where intake is limited by the disease animals will often exhibit preferential selection of higher quality browse. Furthe r studies are required to evaluate the minimum levels of protein and energy supplementation required to ameliorate the adverse effect of trypanosomias is, the nature and quality of protein supplement to achieve these benefits and the influence these have on digestive physiology.